perf(app): reduce redundant data fetching

Share bounded database pools across API repositories, consolidate sync and chat queries, and make mobile refreshes cache-aware and foreground-aware.

Add focused regression coverage, client freshness documentation, and repository agent role configuration.

.codex/agents/architecture-reviewer.toml

@@ -0,0 +1,11 @@
+name = "architecture_reviewer"
+description = "Read-only reviewer for cross-cutting or hard-to-reverse Sauci architecture decisions."
+model = "gpt-5.6-sol"
+model_reasoning_effort = "high"
+sandbox_mode = "read-only"
+developer_instructions = """
+Evaluate the delegated decision against current system boundaries, data flow,
+migration path, operability, reversibility, and verification. Prefer the smallest
+coherent change. Return explicit trade-offs, risks, and a recommendation with
+file-backed evidence. Do not edit files or review unrelated local refactors.
+"""

.codex/agents/database-reviewer.toml

@@ -0,0 +1,12 @@
+name = "database_reviewer"
+description = "Read-only reviewer for Sauci migrations, RLS, authorization, and query boundaries."
+model = "gpt-5.6-terra"
+model_reasoning_effort = "high"
+sandbox_mode = "read-only"
+developer_instructions = """
+Read the applicable AGENTS.md, database migration skill, and migration safety
+documentation. Review only the delegated diff for migration tracking,
+idempotency, authorization and tenant isolation, portability, rollback impact,
+types, and integration coverage. Never mutate a database or edit files. Return
+prioritized line-specific findings with concrete evidence and counterevidence.
+"""

.codex/agents/implementation.toml

@@ -0,0 +1,12 @@
+name = "implementation"
+description = "Default executor for a bounded Sauci product or harness change after scope and acceptance criteria are known."
+model = "gpt-5.6-terra"
+developer_instructions = """
+Read the root and nearest scoped AGENTS.md files plus the applicable repository
+skill. Implement only the delegated objective and preserve unrelated work. Update
+maintained contract documentation and add focused tests when the contract changes.
+Run the required focused checks and return changed files, exact results,
+assumptions, and blockers. Stop for missing authority or a materially ambiguous
+product choice. Do not expand scope or perform external, destructive, production,
+release, or provider writes unless the task explicitly authorizes that action.
+"""

.codex/agents/repo-scout.toml

@@ -0,0 +1,11 @@
+name = "repo_scout"
+description = "Read-only Sauci codebase scout for locating ownership, callers, contracts, tests, and existing patterns."
+model = "gpt-5.6-luna"
+model_reasoning_effort = "low"
+sandbox_mode = "read-only"
+developer_instructions = """
+Read the root and nearest scoped AGENTS.md files. Map only the requested surface.
+Return evidence-backed file paths, symbols, current behavior, dependencies, tests,
+and uncertainties. Do not edit files, make design decisions, or propose broad
+refactors. Do not claim runtime behavior you did not observe.
+"""

.codex/agents/security-reviewer.toml

@@ -0,0 +1,12 @@
+name = "security_reviewer"
+description = "Read-only reviewer for auth, RLS, cryptography, secrets, payments, privileged MCP, and destructive operations."
+model = "gpt-5.6-sol"
+model_reasoning_effort = "high"
+sandbox_mode = "read-only"
+developer_instructions = """
+Perform a scoped threat-boundary review of the delegated change. Trace callers
+through authentication and authorization to the data sink. Prioritize exploitable
+correctness and security risks, include counterevidence, and cite exact files and
+lines. Do not edit files or expand into a repository-wide audit unless explicitly
+requested.
+"""

.codex/agents/test-writer.toml

@@ -0,0 +1,11 @@
+name = "test_writer"
+description = "Focused Sauci regression and contract-test author for already-defined behavior."
+model = "gpt-5.6-terra"
+model_reasoning_effort = "medium"
+developer_instructions = """
+Read the applicable AGENTS.md and testing documentation. Test the intended
+observable contract at the lowest useful layer while preserving real auth,
+authorization, tenant, and couple boundaries. Do not weaken assertions to
+accommodate a failure. Run the focused test and return files changed, exact
+commands, results, and any product defect exposed by the test.
+"""

.codex/agents/verifier.toml

@@ -0,0 +1,11 @@
+name = "verifier"
+description = "Independent Sauci behavior verifier that drives completed work and returns evidence, not fixes."
+model = "gpt-5.6-terra"
+model_reasoning_effort = "medium"
+developer_instructions = """
+Read the applicable AGENTS.md and .codex/skills/verify/SKILL.md. Independently
+exercise the delegated acceptance criteria against the running non-production
+product. You may write generated proof only under evidence/. Do not edit source,
+tests, configuration, or acceptance criteria. Return expected behavior, observed
+behavior, evidence paths, environment limitations, and a works or broken verdict.
+"""

.codex/config.toml

@@ -0,0 +1,5 @@
+[agents]
+enabled = true
+max_concurrent_threads_per_session = 3
+default_subagent_model = "gpt-5.6-terra"
+default_subagent_reasoning_effort = "medium"

AGENTS.md

@@ -17,7 +17,10 @@ MCP service in one npm/Turborepo workspace.
 5. Read `apps/mobile/DESIGN.md` before mobile UI work.
 6. Keep shared package exports type-only and route them through `src/index.ts`.
 7. Do not commit secrets, generated evidence, local logs, or runtime state.
-8. Scope work to the task. Use high-effort reviewers only for the risk triggers in
+8. Scope work to the task. Route bounded implementation through the project
+   `implementation` agent when delegation is useful; the primary agent retains
+   acceptance, review, and final verification. Do not delegate trivial edits.
+9. Use high-effort reviewers only for the risk triggers in
    `docs/agents/routing.md`.
 
 ## Repository map

apps/api/.env.example

@@ -3,6 +3,14 @@ DATABASE_URL=postgresql://sauci:sauci_local_only@127.0.0.1:54320/sauci
 SUPABASE_AUTH_URL=https://your-project.supabase.co
 SUPABASE_AUTH_AUDIENCE=authenticated
 
+# Optional connection-pool bounds. The API process opens one pool and shares it
+# across every repository, so these are the process-wide limits, not per-domain
+# ones. Raising DATABASE_POOL_MAX raises the server connections this instance can
+# hold; keep the total across instances inside the database's own limit.
+# DATABASE_POOL_MAX=10
+# DATABASE_POOL_IDLE_TIMEOUT_MS=30000
+# DATABASE_POOL_CONNECTION_TIMEOUT_MS=10000
+
 # Server-only hosted Auth Admin credential. Used for account deletion and for
 # enriching admin user lists; it is never exposed to the browser or used as a
 # Supabase database client.

apps/api/src/config.ts

@@ -7,6 +7,9 @@ const baseSchema = z.object({
   NODE_ENV: z.enum(['development', 'test', 'production']).default('development'),
   PORT: z.coerce.number().int().min(1).max(65535).default(3003),
   DATABASE_URL: z.string().url(),
+  DATABASE_POOL_MAX: z.coerce.number().int().min(1).max(200).default(10),
+  DATABASE_POOL_IDLE_TIMEOUT_MS: z.coerce.number().int().min(0).max(3_600_000).default(30_000),
+  DATABASE_POOL_CONNECTION_TIMEOUT_MS: z.coerce.number().int().min(0).max(60_000).default(10_000),
   SUPABASE_AUTH_URL: z.string().url().optional(),
   SUPABASE_AUTH_ISSUER: z.string().url().optional(),
   SUPABASE_AUTH_JWKS_URL: z.string().url().optional(),
@@ -28,6 +31,7 @@ export interface AppConfig {
   nodeEnv: 'development' | 'test' | 'production';
   port: number;
   databaseUrl: string;
+  databasePool: { max: number; idleTimeoutMillis: number; connectionTimeoutMillis: number };
   authIssuer: string;
   authJwksUrl?: string;
   authAudience: string;
@@ -81,6 +85,11 @@ export function loadConfig(env: NodeJS.ProcessEnv = process.env): AppConfig {
     nodeEnv: parsed.NODE_ENV,
     port: parsed.PORT,
     databaseUrl: parsed.DATABASE_URL,
+    databasePool: {
+      max: parsed.DATABASE_POOL_MAX,
+      idleTimeoutMillis: parsed.DATABASE_POOL_IDLE_TIMEOUT_MS,
+      connectionTimeoutMillis: parsed.DATABASE_POOL_CONNECTION_TIMEOUT_MS,
+    },
     authIssuer,
     authJwksUrl,
     authAudience: parsed.SUPABASE_AUTH_AUDIENCE,

apps/api/src/db/pool.ts

@@ -0,0 +1,50 @@
+import { Pool } from 'pg';
+
+/**
+ * A repository is constructed either from a connection string, in which case it
+ * owns the pool it creates and must end it, or from a pool the caller owns. The
+ * API process takes the second path so every domain shares one bounded pool
+ * instead of opening a default-sized pool per repository; tests keep taking the
+ * first so each suite stays independently closable.
+ */
+export type DatabaseConnection = string | Pool;
+
+export interface DatabasePoolOptions {
+  /** Server-wide ceiling on concurrent PostgreSQL connections. */
+  max?: number;
+  idleTimeoutMillis?: number;
+  connectionTimeoutMillis?: number;
+}
+
+/**
+ * `pg` defaults to ten connections per pool, which multiplied by one pool per
+ * repository. One shared pool of the same size keeps the same headroom for a
+ * single API process while bounding what a self-hosted PostgreSQL must accept.
+ */
+export const DEFAULT_POOL_MAX = 10;
+
+export function createDatabasePool(databaseUrl: string, options: DatabasePoolOptions = {}): Pool {
+  return new Pool({
+    connectionString: databaseUrl,
+    max: options.max ?? DEFAULT_POOL_MAX,
+    ...(options.idleTimeoutMillis === undefined ? {} : { idleTimeoutMillis: options.idleTimeoutMillis }),
+    ...(options.connectionTimeoutMillis === undefined ? {} : { connectionTimeoutMillis: options.connectionTimeoutMillis }),
+  });
+}
+
+export interface ResolvedPool {
+  pool: Pool;
+  /** True when this repository created the pool and is responsible for ending it. */
+  owned: boolean;
+}
+
+export function resolvePool(connection: DatabaseConnection): ResolvedPool {
+  return typeof connection === 'string'
+    ? { pool: new Pool({ connectionString: connection }), owned: true }
+    : { pool: connection, owned: false };
+}
+
+/** Ends the pool only when this repository created it, so shared pools survive. */
+export async function closeResolvedPool(pool: Pool, owned: boolean): Promise<void> {
+  if (owned) await pool.end();
+}

apps/api/src/db/repository.ts

@@ -2,6 +2,7 @@ import type { FeatureInterestResponse, Profile } from '@sauci/shared';
 import { and, eq, sql } from 'drizzle-orm';
 import { drizzle, type NodePgDatabase } from 'drizzle-orm/node-postgres';
 import { Pool } from 'pg';
+import { closeResolvedPool, resolvePool, type DatabaseConnection } from './pool.js';
 import type { AuthIdentity } from '../auth.js';
 import { featureInterests, profiles, type ProfileRow } from './schema.js';
 
@@ -44,10 +45,13 @@ function toProfile(row: ProfileRow): MobileCompatibleProfile {
 
 export class PostgresRepository implements ApiRepository {
   private readonly pool: Pool;
+  private readonly ownsPool: boolean;
   private readonly db: NodePgDatabase;
 
-  constructor(databaseUrl: string) {
-    this.pool = new Pool({ connectionString: databaseUrl });
+  constructor(connection: DatabaseConnection) {
+    const resolved = resolvePool(connection);
+    this.pool = resolved.pool;
+    this.ownsPool = resolved.owned;
     this.db = drizzle(this.pool);
   }
 
@@ -55,7 +59,21 @@ export class PostgresRepository implements ApiRepository {
     await this.db.select({ id: profiles.id }).from(profiles).limit(1);
   }
 
+  /**
+   * Idempotent for the common case. `GET /v1/me` runs on every app start and on
+   * every session refresh, and the previous unconditional upsert made each of
+   * those a write that advanced `auth_synced_at` and produced dead row versions
+   * for autovacuum. The only fields this sync can actually change are the ones
+   * the conflict clause sets, so a profile that already carries the identity's
+   * email is returned as read and nothing is written. First-use creation and
+   * email enrichment keep their existing behaviour.
+   */
   async upsertProfile(identity: AuthIdentity): Promise<MobileCompatibleProfile> {
+    const [existing] = await this.db.select().from(profiles).where(eq(profiles.id, identity.id)).limit(1);
+    if (existing && (identity.email === null || identity.email === undefined || existing.email === identity.email)) {
+      return toProfile(existing);
+    }
+
     const [row] = await this.db.insert(profiles).values({
       id: identity.id,
       name: identity.name,
@@ -93,6 +111,6 @@ export class PostgresRepository implements ApiRepository {
   }
 
   async close(): Promise<void> {
-    await this.pool.end();
+    await closeResolvedPool(this.pool, this.ownsPool);
   }
 }

apps/api/src/domains/account-operations/repository.ts

@@ -1,4 +1,5 @@
 import { Pool, type PoolClient, type QueryResultRow } from 'pg';
+import { closeResolvedPool, resolvePool, type DatabaseConnection } from '../../db/pool.js';
 import { AccountOperationError } from './types.js';
 
 interface ProfileOperationRecord extends QueryResultRow {
@@ -63,9 +64,12 @@ async function lockCoupleAndPartner(
 
 export class PostgresAccountOperationsRepository implements AccountOperationsRepository {
   private readonly pool: Pool;
+  private readonly ownsPool: boolean;
 
-  constructor(databaseUrl: string) {
-    this.pool = new Pool({ connectionString: databaseUrl });
+  constructor(connection: DatabaseConnection) {
+    const resolved = resolvePool(connection);
+    this.pool = resolved.pool;
+    this.ownsPool = resolved.owned;
   }
 
   async deleteRelationship(userId: string): Promise<DestructiveOperationResult> {
@@ -135,7 +139,7 @@ export class PostgresAccountOperationsRepository implements AccountOperationsRep
   }
 
   async close(): Promise<void> {
-    await this.pool.end();
+    await closeResolvedPool(this.pool, this.ownsPool);
   }
 }
 

apps/api/src/domains/admin/repository.ts

@@ -1,4 +1,5 @@
 import { Pool, type PoolClient, type QueryResultRow } from 'pg';
+import { closeResolvedPool, resolvePool, type DatabaseConnection } from '../../db/pool.js';
 import { readFile } from 'node:fs/promises';
 import { resolve, sep } from 'node:path';
 import { AdminError, type AdminPrincipal, type AdminQuery } from './types.js';
@@ -139,9 +140,10 @@ export interface AdminRepository {
 
 export class PostgresAdminRepository implements AdminRepository {
   private readonly pool: Pool;
-  constructor(databaseUrl: string, private readonly options: {
+  private readonly ownsPool: boolean;
+  constructor(connection: DatabaseConnection, private readonly options: {
     adminPrivateKeyJwk?: string; mediaRoot?: string; authDirectory?: AdminAuthDirectory;
-  } = {}) { this.pool = new Pool({ connectionString: databaseUrl }); }
+  } = {}) { const resolved = resolvePool(connection); this.pool = resolved.pool; this.ownsPool = resolved.owned; }
 
   async principal(userId: string): Promise<AdminPrincipal> {
     const result = await this.pool.query<{ id: string; user_id: string; role: AdminPrincipal['role']; permissions: string[] }>(
@@ -356,5 +358,5 @@ export class PostgresAdminRepository implements AdminRepository {
     await client.query('insert into audit_logs(admin_user_id,actor_user_id,table_name,action,record_id,old_values,new_values) values($1,$2,$3,$4,$5,$6,$7)', [principal.adminId, principal.userId, table, action, recordId || null, redactAudit(oldValues), redactAudit(newValues)]);
   }
 
-  async close(): Promise<void> { await this.pool.end(); }
+  async close(): Promise<void> { await closeResolvedPool(this.pool, this.ownsPool); }
 }

apps/api/src/domains/answers/repository.ts

@@ -1,4 +1,5 @@
 import { Pool, type PoolClient } from 'pg';
+import { closeResolvedPool, resolvePool, type DatabaseConnection } from '../../db/pool.js';
 import { AnswersError, calculateMatchType, type Answer, type MatchType, type QuestionType, type ResponseData } from './types.js';
 
 interface ContextRow { couple_id: string | null; gender: string | null; max_intensity: number; is_premium: boolean }
@@ -44,7 +45,7 @@ export interface AnswersRepository {
   submit(userId: string, input: SubmitInput): Promise<{ response: ResponseRow; match: (MatchRow & { question: QuestionRow }) | null }>;
   update(userId: string, input: UpdateInput): Promise<Record<string, unknown>>;
   responses(userId: string, page: number, limit: number): Promise<{ responses: unknown[]; totalCount: number }>;
-  matches(userId: string, page: number, limit: number, archived: boolean): Promise<{ matches: unknown[]; totalCount: number }>;
+  matches(userId: string, page: number, limit: number, archived: boolean): Promise<{ matches: unknown[]; totalCount: number | null; hasMore: boolean }>;
   markSeen(userId: string, ids: string[]): Promise<void>;
   archive(userId: string, matchId: string, archived: boolean): Promise<void>;
   streak(userId: string): Promise<CoupleStreakView | null>;
@@ -53,8 +54,9 @@ export interface AnswersRepository {
 
 export class PostgresAnswersRepository implements AnswersRepository {
   private readonly pool: Pool;
+  private readonly ownsPool: boolean;
   private zones: Promise<Set<string>> | null = null;
-  constructor(databaseUrl: string) { this.pool = new Pool({ connectionString: databaseUrl }); }
+  constructor(connection: DatabaseConnection) { const resolved = resolvePool(connection); this.pool = resolved.pool; this.ownsPool = resolved.owned; }
 
   private async context(client: Pool | PoolClient, userId: string): Promise<ContextRow> {
     const result = await client.query<ContextRow>('select couple_id, gender, max_intensity, is_premium from profiles where id=$1', [userId]);
@@ -230,12 +232,23 @@ export class PostgresAnswersRepository implements AnswersRepository {
     return {responses:rows.rows.map(this.dates),totalCount:count.rows[0]?.count??0};
   }
 
+  /**
+   * Reading one row past the page decides `hasMore` exactly, and the total — which
+   * the client only records when it refreshes — is counted on the first page only
+   * instead of on every scroll. Unread is aggregated once per couple rather than as
+   * a correlated count per row: the sort key depends on it, so the old subquery
+   * already ran for every candidate match, not just the twenty that were returned.
+   */
   async matches(userId:string,page:number,limit:number,archived:boolean){
     const ctx=await this.context(this.pool,userId); const offset=page*limit;
-    const params=[userId,ctx.couple_id,archived,limit,offset];
-    const base=`from matches m join questions q on q.id=m.question_id left join match_archives a on a.match_id=m.id and a.user_id=$1 where m.couple_id=$2 and (($3 and a.id is not null) or (not $3 and a.id is null))`;
-    const [rows,count]=await Promise.all([this.pool.query(`select m.*,json_build_object('id',q.id,'pack_id',q.pack_id,'text',q.text,'partner_text',q.partner_text,'intensity',q.intensity,'question_type',q.question_type,'config',q.config,'created_at',q.created_at) question,(select count(*)::int from messages msg where msg.match_id=m.id and msg.user_id<>$1 and msg.read_at is null) "unreadCount" ${base} order by "unreadCount" desc,m.created_at desc limit $4 offset $5`,params),this.pool.query<{count:number}>(`select count(*)::int count ${base}`,params.slice(0,3))]);
-    return {matches:rows.rows.map(this.dates),totalCount:count.rows[0]?.count??0};
+    const params=[userId,ctx.couple_id,archived,limit+1,offset];
+    const from=`from matches m join questions q on q.id=m.question_id left join match_archives a on a.match_id=m.id and a.user_id=$1`;
+    const where=`where m.couple_id=$2 and (($3 and a.id is not null) or (not $3 and a.id is null))`;
+    const unread=`unread as (select msg.match_id,count(*)::int c from messages msg join matches um on um.id=msg.match_id and um.couple_id=$2 where msg.user_id<>$1 and msg.read_at is null group by msg.match_id)`;
+    const [rows,count]=await Promise.all([
+      this.pool.query(`with ${unread} select m.*,json_build_object('id',q.id,'pack_id',q.pack_id,'text',q.text,'partner_text',q.partner_text,'intensity',q.intensity,'question_type',q.question_type,'config',q.config,'created_at',q.created_at) question,coalesce(u.c,0) "unreadCount" ${from} left join unread u on u.match_id=m.id ${where} order by "unreadCount" desc,m.created_at desc limit $4 offset $5`,params),
+      page===0?this.pool.query<{count:number}>(`select count(*)::int count ${from} ${where}`,params.slice(0,3)):null]);
+    return {matches:rows.rows.slice(0,limit).map(this.dates),totalCount:count?count.rows[0]?.count??0:null,hasMore:rows.rows.length>limit};
   }
   async markSeen(userId:string,ids:string[]){const ctx=await this.context(this.pool,userId);await this.pool.query('update matches set is_new=false where couple_id=$1 and id=any($2::uuid[])',[ctx.couple_id,ids]);}
   async archive(userId:string,matchId:string,archived:boolean){const ctx=await this.context(this.pool,userId);const found=await this.pool.query('select 1 from matches where id=$1 and couple_id=$2',[matchId,ctx.couple_id]);if(!found.rowCount)throw new AnswersError('match_not_found',404,'Match was not found');if(archived)await this.pool.query('insert into match_archives(match_id,user_id) values($1,$2) on conflict do nothing',[matchId,userId]);else await this.pool.query('delete from match_archives where match_id=$1 and user_id=$2',[matchId,userId]);}
@@ -304,5 +317,5 @@ export class PostgresAnswersRepository implements AnswersRepository {
   }
   private async tx<T>(fn:(client:PoolClient)=>Promise<T>):Promise<T>{const c=await this.pool.connect();try{await c.query('begin');const value=await fn(c);await c.query('commit');return value;}catch(e){await c.query('rollback');throw e;}finally{c.release();}}
   private dates<T extends Record<string,any>>(row:T):T{return Object.fromEntries(Object.entries(row).map(([k,v])=>[k,v instanceof Date?v.toISOString():v])) as T;}
-  async close(){await this.pool.end();}
+  async close(){await closeResolvedPool(this.pool,this.ownsPool);}
 }

apps/api/src/domains/app-data/repository.ts

@@ -1,4 +1,5 @@
 import { Pool, type QueryResultRow } from 'pg';
+import { closeResolvedPool, resolvePool, type DatabaseConnection } from '../../db/pool.js';
 
 export interface PackContext { id: string; name: string; icon: string | null }
 export interface AppQuestion {
@@ -19,6 +20,50 @@ export interface StrokeSegment {
 }
 export interface LiveDrawState { strokes: StrokeSegment[]; revision: number; updated_at: string | null; updated_by: string | null }
 
+/**
+ * A change summary rather than a payload. The mobile app used to re-fetch profile,
+ * couple, matches, both pending directions and enabled packs every five seconds to
+ * notice partner activity; it now compares this summary with the last one it saw and
+ * refreshes only the domains whose marker actually moved. Every field is a marker,
+ * not display data, so the response stays a few hundred bytes whatever the couple's
+ * history looks like.
+ */
+export interface SyncSummary {
+  server_time: string;
+  couple_id: string | null;
+  profile_updated_at: string | null;
+  partner_id: string | null;
+  partner_updated_at: string | null;
+  /** Matches visible to this member: archiving one of them moves the count. */
+  match_count: number;
+  new_match_count: number;
+  latest_match_at: string | null;
+  /** Partner answered, this member has not. */
+  pending_yours: number;
+  /** This member answered, partner has not. */
+  pending_theirs: number;
+  unread_total: number;
+  /** Digest of the enabled pack ids, so an equal-and-opposite toggle is still a change. */
+  enabled_packs_fingerprint: string;
+  /**
+   * Digest of each visible match's type and response summary. `match_count` /
+   * `new_match_count` / `latest_match_at` only move when a match is created,
+   * archived or unarchived — not when a partner edits an existing response and
+   * changes its `match_type` or `response_summary` — so this fingerprint is
+   * what actually notices that edit.
+   */
+  match_state_fingerprint: string;
+  /**
+   * Digest of each visible match's unread count. `unread_total` can stay equal
+   * while unread messages redistribute between matches (one read, another
+   * receives a message), which reorders the unread-first list without moving
+   * the total; this fingerprint is what notices that.
+   */
+  match_unread_fingerprint: string;
+  /** couple_streaks.updated_at, so a partner's answer can silently refresh an already-loaded streak. */
+  streak_updated_at: string | null;
+}
+
 export class AppDataError extends Error {
   constructor(public readonly code: 'not_found' | 'no_couple' | 'not_recipient' | 'rate_limited' | 'revision_conflict', message: string, public readonly status: 403 | 404 | 409 | 429, public readonly details?: Record<string, unknown>) { super(message); }
 }
@@ -31,6 +76,7 @@ export interface AppDataRepository {
   markMediaViewed(userId: string, messageId: string, expiresAt: string | null): Promise<{ media_viewed_at: string; media_expires_at: string | null }>;
   nudgeStatus(userId: string): Promise<{ last_nudge_sent_at: string | null }>;
   sendNudge(userId: string): Promise<{ success: true; notification_sent: boolean; reason?: string; next_nudge_available_at: string }>;
+  syncSummary(userId: string): Promise<SyncSummary>;
   getLiveDraw(userId: string): Promise<LiveDrawState>;
   putLiveDraw(userId: string, strokes: StrokeSegment[], baseRevision: number): Promise<LiveDrawState>;
   close(): Promise<void>;
@@ -38,11 +84,22 @@ export interface AppDataRepository {
 
 interface QuestionRow extends QueryResultRow, Omit<AppQuestion, 'created_at'> { created_at: Date }
 
+interface SyncRow extends QueryResultRow {
+  server_time: Date; couple_id: string | null; profile_updated_at: Date | null;
+  partner_id: string | null; partner_updated_at: Date | null;
+  match_count: number | null; new_match_count: number | null; latest_match_at: Date | null;
+  pending_yours: number | null; pending_theirs: number | null; unread_total: number | null;
+  enabled_packs_fingerprint: string | null;
+  match_state_fingerprint: string | null; match_unread_fingerprint: string | null;
+  streak_updated_at: Date | null;
+}
+
 function question(row: QuestionRow): AppQuestion { return { ...row, created_at: row.created_at.toISOString() }; }
 
 export class PostgresAppDataRepository implements AppDataRepository {
   private readonly pool: Pool;
-  constructor(databaseUrl: string) { this.pool = new Pool({ connectionString: databaseUrl }); }
+  private readonly ownsPool: boolean;
+  constructor(connection: DatabaseConnection) { const resolved = resolvePool(connection); this.pool = resolved.pool; this.ownsPool = resolved.owned; }
 
   private async visiblePack(userId: string, packId: string): Promise<PackContext> {
     const result = await this.pool.query<PackContext>(`
@@ -189,5 +246,75 @@ export class PostgresAppDataRepository implements AppDataRepository {
     }
     return { strokes: row.strokes, revision: Number(row.revision), updated_at: row.updated_at.toISOString(), updated_by: row.updated_by };
   }
-  async close(): Promise<void> { await this.pool.end(); }
+  /**
+   * One round trip, all scalar subqueries, nothing that grows with the couple's
+   * history. An unpaired member's couple-scoped markers all collapse to zero or null
+   * because `me.couple_id` is null, so the endpoint stays valid before pairing.
+   */
+  async syncSummary(userId: string): Promise<SyncSummary> {
+    const result = await this.pool.query<SyncRow>(`
+      with me as (select id, couple_id, updated_at from profiles where id = $1),
+      visible as (
+        select m.id, m.is_new, m.created_at, m.match_type, m.response_summary from matches m, me
+        where m.couple_id = me.couple_id
+          and not exists (select 1 from match_archives a where a.match_id = m.id and a.user_id = me.id)
+      ),
+      visible_unread as (
+        select v.id as match_id, count(msg.id)::int as c
+        from visible v
+        left join messages msg on msg.match_id = v.id and msg.user_id <> (select id from me)
+          and msg.read_at is null and msg.deleted_at is null
+          and not exists (select 1 from message_deletions d where d.message_id = msg.id and d.user_id = (select id from me))
+        group by v.id
+      )
+      select
+        now() as server_time,
+        me.couple_id,
+        me.updated_at as profile_updated_at,
+        (select p.id from profiles p where p.couple_id = me.couple_id and p.id <> me.id order by p.id limit 1) as partner_id,
+        (select max(p.updated_at) from profiles p where p.couple_id = me.couple_id and p.id <> me.id) as partner_updated_at,
+        (select count(*)::int from visible) as match_count,
+        (select count(*)::int from visible where is_new) as new_match_count,
+        (select max(created_at) from visible) as latest_match_at,
+        (select count(*)::int from responses r join questions q on q.id = r.question_id
+           where r.couple_id = me.couple_id and q.deleted_at is null and r.user_id <> me.id
+             and not exists (select 1 from responses o
+               where o.question_id = r.question_id and o.couple_id = me.couple_id and o.user_id = me.id)) as pending_yours,
+        (select count(*)::int from responses r join questions q on q.id = r.question_id
+           where r.couple_id = me.couple_id and q.deleted_at is null and r.user_id = me.id
+             and not exists (select 1 from responses o
+               where o.question_id = r.question_id and o.couple_id = me.couple_id and o.user_id <> me.id)) as pending_theirs,
+        (select count(*)::int from messages msg join matches ma on ma.id = msg.match_id
+           where ma.couple_id = me.couple_id and msg.user_id <> me.id and msg.read_at is null and msg.deleted_at is null
+             and not exists (select 1 from message_deletions d where d.message_id = msg.id and d.user_id = me.id)) as unread_total,
+        (select md5(coalesce(string_agg(cp.pack_id::text, ',' order by cp.pack_id), ''))
+           from couple_packs cp where cp.couple_id = me.couple_id and cp.enabled) as enabled_packs_fingerprint,
+        (select md5(coalesce(string_agg(v.id::text || ':' || v.match_type || ':' || coalesce(v.response_summary::text, ''), ',' order by v.id), ''))
+           from visible v) as match_state_fingerprint,
+        (select md5(coalesce(string_agg(vu.match_id::text || ':' || vu.c, ',' order by vu.match_id), ''))
+           from visible_unread vu) as match_unread_fingerprint,
+        (select cs.updated_at from couple_streaks cs where cs.couple_id = me.couple_id) as streak_updated_at
+      from me`, [userId]);
+    const row = result.rows[0];
+    if (!row) throw new AppDataError('not_found', 'Profile not found', 404);
+    return {
+      server_time: row.server_time.toISOString(),
+      couple_id: row.couple_id,
+      profile_updated_at: row.profile_updated_at?.toISOString() ?? null,
+      partner_id: row.partner_id,
+      partner_updated_at: row.partner_updated_at?.toISOString() ?? null,
+      match_count: row.match_count ?? 0,
+      new_match_count: row.new_match_count ?? 0,
+      latest_match_at: row.latest_match_at?.toISOString() ?? null,
+      pending_yours: row.pending_yours ?? 0,
+      pending_theirs: row.pending_theirs ?? 0,
+      unread_total: row.unread_total ?? 0,
+      enabled_packs_fingerprint: row.enabled_packs_fingerprint ?? '',
+      match_state_fingerprint: row.match_state_fingerprint ?? '',
+      match_unread_fingerprint: row.match_unread_fingerprint ?? '',
+      streak_updated_at: row.streak_updated_at?.toISOString() ?? null,
+    };
+  }
+
+  async close(): Promise<void> { await closeResolvedPool(this.pool, this.ownsPool); }
 }

apps/api/src/domains/app-data/routes.ts

@@ -44,6 +44,11 @@ export function registerAppDataRoutes(app: App, repository: AppDataRepository):
     const result = await run(() => repository.markMediaViewed(c.get('identity').id, id.data, body.data.expires_at));
     return result.ok ? c.json(result.value) : c.json(error(result.cause.code, result.cause.message), result.cause.status);
   });
+  // The client polls this instead of re-fetching every domain; see SyncSummary.
+  app.get('/v1/me/sync', async c => {
+    const result = await run(() => repository.syncSummary(c.get('identity').id));
+    return result.ok ? c.json(result.value) : c.json(error(result.cause.code, result.cause.message), result.cause.status);
+  });
   app.get('/v1/me/nudge-status', async c => c.json(await repository.nudgeStatus(c.get('identity').id)));
   app.post('/v1/me/nudge', async c => {
     const result = await run(() => repository.sendNudge(c.get('identity').id));

apps/api/src/domains/billing/repository.ts

@@ -1,4 +1,5 @@
 import { Pool, type PoolClient, type QueryResultRow } from 'pg';
+import { closeResolvedPool, resolvePool, type DatabaseConnection } from '../../db/pool.js';
 import { BillingError, type RedemptionResult, type RevenueCatWebhook, type SubscriptionStatus } from './types.js';
 
 interface ProfileRecord extends QueryResultRow {
@@ -43,9 +44,12 @@ async function transaction<T>(pool: Pool, operation: (client: PoolClient) => Pro
 
 export class PostgresBillingRepository implements BillingRepository {
   private readonly pool: Pool;
+  private readonly ownsPool: boolean;
 
-  constructor(databaseUrl: string) {
-    this.pool = new Pool({ connectionString: databaseUrl });
+  constructor(connection: DatabaseConnection) {
+    const resolved = resolvePool(connection);
+    this.pool = resolved.pool;
+    this.ownsPool = resolved.owned;
   }
 
   async processRevenueCatEvent(
@@ -207,6 +211,6 @@ export class PostgresBillingRepository implements BillingRepository {
   }
 
   async close(): Promise<void> {
-    await this.pool.end();
+    await closeResolvedPool(this.pool, this.ownsPool);
   }
 }

apps/api/src/domains/chat/repository.ts

@@ -1,4 +1,5 @@
 import { Pool, type QueryResultRow } from 'pg';
+import { closeResolvedPool, resolvePool, type DatabaseConnection } from '../../db/pool.js';
 
 export type ChatMediaType = 'image' | 'video' | null;
 export type ReportReason = 'harassment' | 'spam' | 'inappropriate_content' | 'other';
@@ -45,8 +46,37 @@ export class ChatError extends Error {
   }
 }
 
+/**
+ * The reply to a message poll. A request without a cursor is a full snapshot; a
+ * request with one carries only what changed, so a quiet chat costs an empty
+ * array rather than the whole backlog.
+ */
+export interface MessagesPage {
+  /** Newest first. Messages created or changed since the cursor, or the snapshot. */
+  messages: ChatMessage[];
+  /** Messages the caller deleted for themselves since the cursor. */
+  removed_ids: string[];
+  /** Cursor to send as `since` on the next poll. */
+  server_time: string;
+  /** True when `messages` is a complete snapshot the client may replace its cache with. */
+  complete: boolean;
+  /** Present only when the caller asked for it, folding the typing poll into this one. */
+  typing?: PartnerTyping;
+}
+
+export interface PartnerTyping {
+  typing: boolean;
+  expires_at: string | null;
+}
+
+export interface ListMessagesOptions {
+  /** ISO timestamp from a previous `server_time`. Omit for a full snapshot. */
+  since?: string;
+  includeTyping?: boolean;
+}
+
 export interface ChatRepository {
-  listMessages(userId: string, matchId: string): Promise<ChatMessage[]>;
+  listMessages(userId: string, matchId: string, options?: ListMessagesOptions): Promise<MessagesPage>;
   sendText(userId: string, matchId: string, content: string): Promise<ChatMessage>;
   unreadCounts(userId: string): Promise<{ total: number; by_match: Record<string, number> }>;
   markMatchRead(userId: string, matchId: string): Promise<{ updated: number; read_at: string }>;
@@ -55,13 +85,21 @@ export interface ChatRepository {
   deleteForEveryone(userId: string, messageId: string): Promise<ChatMessage>;
   report(userId: string, messageId: string, reason: ReportReason): Promise<void>;
   setTyping(userId: string, matchId: string, ttlMs: number): Promise<void>;
-  getPartnerTyping(userId: string, matchId: string): Promise<{ typing: boolean; expires_at: string | null }>;
+  getPartnerTyping(userId: string, matchId: string): Promise<PartnerTyping>;
   close(): Promise<void>;
 }
 
+// `media_expired` is derived rather than read. Nothing ever writes the stored
+// column — it is inserted `false` and never updated — so a video that reached
+// `media_expires_at` still arrived flagged as playable, while the media itself
+// was already refused (see `accessible` in the media repository, which treats
+// `media_expired or media_expires_at <= now()` as gone). Deriving it here is the
+// same rule the media side already applies, and it is what makes the client's
+// "Video expired" state reachable at all.
 const columns = `m.id, m.match_id, m.user_id, m.content, m.created_at, m.read_at,
   m.delivered_at, m.deleted_at, m.media_path, m.media_type, m.media_expires_at,
-  m.media_expired, m.media_viewed_at, m.version, m.encrypted_content,
+  (m.media_expired or (m.media_expires_at is not null and m.media_expires_at <= now())) as media_expired,
+  m.media_viewed_at, m.version, m.encrypted_content,
   m.encryption_iv, m.keys_metadata, m.moderation_status, m.flag_reason, m.category`;
 
 function iso(value: Date | null): string | null {
@@ -82,9 +120,12 @@ function toMessage(row: MessageRecord): ChatMessage {
 
 export class PostgresChatRepository implements ChatRepository {
   private readonly pool: Pool;
+  private readonly ownsPool: boolean;
 
-  constructor(databaseUrl: string) {
-    this.pool = new Pool({ connectionString: databaseUrl });
+  constructor(connection: DatabaseConnection) {
+    const resolved = resolvePool(connection);
+    this.pool = resolved.pool;
+    this.ownsPool = resolved.owned;
   }
 
   private async assertMatchAccess(userId: string, matchId: string): Promise<void> {
@@ -112,20 +153,68 @@ export class PostgresChatRepository implements ChatRepository {
     return row;
   }
 
-  async listMessages(userId: string, matchId: string): Promise<ChatMessage[]> {
+  /**
+   * Without `since` this is the previous behaviour: the newest 500 visible messages.
+   * With `since` it returns only rows whose visible state moved after that instant —
+   * new messages, existing ones whose delivery, read, deletion or media-view
+   * timestamp advanced, and videos whose media expired inside the window — plus the
+   * ids the caller has since deleted for themselves.
+   *
+   * Moderation metadata (`moderation_status`, `flag_reason`, `category`) is not
+   * covered: the classifier and the admin tool rewrite those columns without
+   * advancing any timestamp, so a delta cannot see them move. No client renders
+   * them today, so nothing user-visible goes stale; giving them a cursor would
+   * mean adding a column to `messages`.
+   * Rows are returned whole rather than as patches so the client merges by id and
+   * needs no second shape to interpret.
+   *
+   * The returned cursor is deliberately a couple of seconds behind the server clock:
+   * a transaction that started before this read but committed after it would
+   * otherwise fall into the gap between two polls. The overlap re-delivers a handful
+   * of rows the client already has, which its merge-by-id absorbs.
+   */
+  async listMessages(userId: string, matchId: string, options: ListMessagesOptions = {}): Promise<MessagesPage> {
     await this.assertMatchAccess(userId, matchId);
-    const result = await this.pool.query<MessageRecord>(
+    const since = options.since ?? null;
+    const visible = `not exists (select 1 from message_deletions d where d.message_id = m.id and d.user_id = $2)`;
+    // Expiry is the one visible change no row write announces: the clock crosses
+    // `media_expires_at` and nothing is updated, so no timestamp moves past the
+    // cursor. Comparing the deadline against the window instead emits the row in
+    // the single poll whose `(since, now()]` contains it, which is exactly when
+    // the derived `media_expired` above flips.
+    const changed = `(m.created_at > $3 or m.read_at > $3 or m.delivered_at > $3
+        or m.deleted_at > $3 or m.media_viewed_at > $3
+        or (m.media_expires_at > $3 and m.media_expires_at <= now()))`;
+
+    const [clock, messages, removed, typing] = await Promise.all([
+      this.pool.query<{ cursor: Date }>(`select now() - interval '2 seconds' as cursor`),
+      this.pool.query<MessageRecord>(
         `select ${columns}
            from messages m
-        where m.match_id = $1
-          and not exists (
-            select 1 from message_deletions d where d.message_id = m.id and d.user_id = $2
-          )
+          where m.match_id = $1 and ${visible}${since === null ? '' : ` and ${changed}`}
           order by m.created_at desc, m.id desc
           limit 500`,
-      [matchId, userId],
-    );
-    return result.rows.map(toMessage);
+        since === null ? [matchId, userId] : [matchId, userId, since],
+      ),
+      since === null
+        ? null
+        : this.pool.query<{ message_id: string }>(
+            `select d.message_id
+               from message_deletions d
+               join messages m on m.id = d.message_id
+              where m.match_id = $1 and d.user_id = $2 and d.deleted_at > $3`,
+            [matchId, userId, since],
+          ),
+      options.includeTyping ? this.partnerTyping(userId, matchId) : null,
+    ]);
+
+    return {
+      messages: messages.rows.map(toMessage),
+      removed_ids: removed?.rows.map((row) => row.message_id) ?? [],
+      server_time: clock.rows[0]!.cursor.toISOString(),
+      complete: since === null,
+      ...(typing ? { typing } : {}),
+    };
   }
 
   async sendText(userId: string, matchId: string, content: string): Promise<ChatMessage> {
@@ -226,8 +315,8 @@ export class PostgresChatRepository implements ChatRepository {
     );
   }
 
-  async getPartnerTyping(userId: string, matchId: string): Promise<{ typing: boolean; expires_at: string | null }> {
-    await this.assertMatchAccess(userId, matchId);
+  /** Access already asserted by the caller, so the message poll can fold this in for free. */
+  private async partnerTyping(userId: string, matchId: string): Promise<PartnerTyping> {
     const result = await this.pool.query<{ expires_at: Date }>(
       `select expires_at from chat_typing_states
         where match_id = $1 and user_id <> $2 and expires_at > now()
@@ -238,8 +327,13 @@ export class PostgresChatRepository implements ChatRepository {
     return { typing: Boolean(expiresAt), expires_at: iso(expiresAt) };
   }
 
+  async getPartnerTyping(userId: string, matchId: string): Promise<PartnerTyping> {
+    await this.assertMatchAccess(userId, matchId);
+    return this.partnerTyping(userId, matchId);
+  }
+
   async close(): Promise<void> {
-    await this.pool.end();
+    await closeResolvedPool(this.pool, this.ownsPool);
   }
 }
 

apps/api/src/domains/chat/routes.ts

@@ -8,6 +8,7 @@ type AuthenticatedApp = Hono<{ Variables: { identity: AuthIdentity } }>;
 const id = z.string().uuid();
 const sendBody = z.object({ content: z.string().trim().min(1).max(10_000) }).strict();
 const reportBody = z.object({ reason: z.enum(['harassment', 'spam', 'inappropriate_content', 'other']) }).strict();
+const since = z.string().datetime({ offset: true });
 
 function error(code: string, message: string): ApiErrorResponse {
   return { error: { code, message } };
@@ -25,11 +26,20 @@ async function result<T>(operation: () => Promise<T>) {
 export function registerChatRoutes(app: AuthenticatedApp, repository: ChatRepository): void {
   app.get('/v1/chat/unread', async (c) => c.json(await repository.unreadCounts(c.get('identity').id)));
 
+  // `since` turns this into a delta poll and `typing=true` folds the typing check
+  // into the same request. Both are optional: a call with neither still answers with
+  // the full snapshot under the `messages` key it always used.
   app.get('/v1/matches/:matchId/messages', async (c) => {
     const parsedId = id.safeParse(c.req.param('matchId'));
     if (!parsedId.success) return c.json(error('invalid_match_id', 'A valid match ID is required'), 400);
-    const response = await result(() => repository.listMessages(c.get('identity').id, parsedId.data));
-    return response.ok ? c.json({ messages: response.value }) : c.json(error(response.cause.code, response.cause.message), response.cause.status);
+    const rawSince = c.req.query('since');
+    const parsedSince = rawSince === undefined ? undefined : since.safeParse(rawSince);
+    if (parsedSince && !parsedSince.success) return c.json(error('invalid_since', 'since must be an ISO-8601 timestamp'), 400);
+    const response = await result(() => repository.listMessages(c.get('identity').id, parsedId.data, {
+      ...(parsedSince?.success ? { since: parsedSince.data } : {}),
+      includeTyping: c.req.query('typing') === 'true',
+    }));
+    return response.ok ? c.json(response.value) : c.json(error(response.cause.code, response.cause.message), response.cause.status);
   });
 
   app.post('/v1/matches/:matchId/messages', async (c) => {

apps/api/src/domains/couples/repository.ts

@@ -1,5 +1,6 @@
 import type { Couple, Profile } from '@sauci/shared';
 import { Pool, type PoolClient, type QueryResultRow } from 'pg';
+import { closeResolvedPool, resolvePool, type DatabaseConnection } from '../../db/pool.js';
 import { CoupleError, type CoupleStateResponse } from './types.js';
 
 interface ProfileRecord extends QueryResultRow {
@@ -93,9 +94,12 @@ async function transaction<T>(pool: Pool, work: (client: PoolClient) => Promise<
 
 export class PostgresCoupleRepository implements CoupleRepository {
   private readonly pool: Pool;
+  private readonly ownsPool: boolean;
 
-  constructor(databaseUrl: string) {
-    this.pool = new Pool({ connectionString: databaseUrl });
+  constructor(connection: DatabaseConnection) {
+    const resolved = resolvePool(connection);
+    this.pool = resolved.pool;
+    this.ownsPool = resolved.owned;
   }
 
   async getState(userId: string): Promise<CoupleStateResponse> {
@@ -199,6 +203,6 @@ export class PostgresCoupleRepository implements CoupleRepository {
   }
 
   async close(): Promise<void> {
-    await this.pool.end();
+    await closeResolvedPool(this.pool, this.ownsPool);
   }
 }

apps/api/src/domains/dares/repository.ts

@@ -1,4 +1,5 @@
 import { Pool, type PoolClient, type QueryResultRow } from 'pg';
+import { closeResolvedPool, resolvePool, type DatabaseConnection } from '../../db/pool.js';
 
 export type DareStatus =
   | 'pending' | 'active' | 'submitted' | 'completed' | 'expired' | 'declined' | 'cancelled';
@@ -181,9 +182,12 @@ function toSentDare(row: SentDareRecord, viewerId: string): SentDare {
 
 export class PostgresDaresRepository implements DaresRepository {
   private readonly pool: Pool;
+  private readonly ownsPool: boolean;
 
-  constructor(databaseUrl: string) {
-    this.pool = new Pool({ connectionString: databaseUrl });
+  constructor(connection: DatabaseConnection) {
+    const resolved = resolvePool(connection);
+    this.pool = resolved.pool;
+    this.ownsPool = resolved.owned;
   }
 
   /**
@@ -475,6 +479,6 @@ export class PostgresDaresRepository implements DaresRepository {
   }
 
   async close(): Promise<void> {
-    await this.pool.end();
+    await closeResolvedPool(this.pool, this.ownsPool);
   }
 }

apps/api/src/domains/media/repository.ts

@@ -1,5 +1,6 @@
 import { randomUUID } from 'node:crypto';
 import { Pool, type PoolClient, type QueryResultRow } from 'pg';
+import { closeResolvedPool, resolvePool, type DatabaseConnection } from '../../db/pool.js';
 import type { MediaKind, MediaObject, MediaUploadContext } from './types.js';
 
 interface MediaRow extends QueryResultRow {
@@ -28,7 +29,8 @@ function object(row: MediaRow): MediaObject {
 
 export class PostgresMediaRepository implements MediaRepository {
   private readonly pool: Pool;
-  constructor(databaseUrl: string) { this.pool = new Pool({ connectionString: databaseUrl }); }
+  private readonly ownsPool: boolean;
+  constructor(connection: DatabaseConnection) { const resolved = resolvePool(connection); this.pool = resolved.pool; this.ownsPool = resolved.owned; }
 
   async create(userId: string, kind: MediaKind, storageKey: string, mimeType: string, byteSize: number, context: MediaUploadContext) {
     const client = await this.pool.connect();
@@ -102,5 +104,5 @@ export class PostgresMediaRepository implements MediaRepository {
   async acknowledgeDeletion(storageKey: string): Promise<void> {
     await this.pool.query('delete from media_deletion_queue where storage_key=$1',[storageKey]);
   }
-  async close() { await this.pool.end(); }
+  async close(): Promise<void> { await closeResolvedPool(this.pool, this.ownsPool); }
 }

apps/api/src/domains/operations/repository.ts

@@ -1,4 +1,5 @@
 import { Pool, type PoolClient, type QueryResultRow } from 'pg';
+import { closeResolvedPool, resolvePool, type DatabaseConnection } from '../../db/pool.js';
 import type { ClassifierRuntimeConfig, MessageForClassification, OperationItem, ProducerSummary } from './types.js';
 
 interface OutboxRow extends QueryResultRow {
@@ -31,7 +32,8 @@ async function transaction<T>(pool: Pool, work: (client: PoolClient) => Promise<
 
 export class PostgresOperationsRepository implements OperationsRepository {
   private readonly pool: Pool;
-  constructor(databaseUrl: string) { this.pool = new Pool({ connectionString: databaseUrl }); }
+  private readonly ownsPool: boolean;
+  constructor(connection: DatabaseConnection) { const resolved = resolvePool(connection); this.pool = resolved.pool; this.ownsPool = resolved.owned; }
 
   async produce(now: Date, limit=100): Promise<ProducerSummary> {
     return transaction(this.pool, async (client) => {
@@ -312,7 +314,7 @@ export class PostgresOperationsRepository implements OperationsRepository {
   async classify(id:string,status:'safe'|'flagged',reason:string|null,category:string) {
     await this.pool.query('update messages set moderation_status=$2,flag_reason=$3,category=$4 where id=$1',[id,status,reason,category]);
   }
-  async close() { await this.pool.end(); }
+  async close(): Promise<void> { await closeResolvedPool(this.pool, this.ownsPool); }
 }
 
 function streakCopy(days:number) {

apps/api/src/domains/packs/repository.ts

@@ -1,4 +1,5 @@
 import { Pool } from 'pg';
+import { closeResolvedPool, resolvePool, type DatabaseConnection } from '../../db/pool.js';
 
 export interface PackCategory {
   id: string;
@@ -69,9 +70,12 @@ interface ProfilePreferencesRow {
 
 export class PostgresPacksRepository implements PacksRepository {
   private readonly pool: Pool;
+  private readonly ownsPool: boolean;
 
-  constructor(databaseUrl: string) {
-    this.pool = new Pool({ connectionString: databaseUrl });
+  constructor(connection: DatabaseConnection) {
+    const resolved = resolvePool(connection);
+    this.pool = resolved.pool;
+    this.ownsPool = resolved.owned;
   }
 
   private async profile(userId: string): Promise<ProfilePreferencesRow> {
@@ -215,6 +219,6 @@ export class PostgresPacksRepository implements PacksRepository {
   }
 
   async close(): Promise<void> {
-    await this.pool.end();
+    await closeResolvedPool(this.pool, this.ownsPool);
   }
 }

apps/api/src/domains/profile-settings/repository.ts

@@ -1,5 +1,6 @@
 import { randomUUID } from 'node:crypto';
 import { Pool, type QueryResultRow } from 'pg';
+import { closeResolvedPool, resolvePool, type DatabaseConnection } from '../../db/pool.js';
 import type {
   FeedbackSubmission,
   NotificationPreferenceKey,
@@ -80,9 +81,12 @@ function assertChanged(rowCount: number | null): void {
 
 export class PostgresProfileSettingsRepository implements ProfileSettingsRepository {
   private readonly pool: Pool;
+  private readonly ownsPool: boolean;
 
-  constructor(databaseUrl: string) {
-    this.pool = new Pool({ connectionString: databaseUrl });
+  constructor(connection: DatabaseConnection) {
+    const resolved = resolvePool(connection);
+    this.pool = resolved.pool;
+    this.ownsPool = resolved.owned;
   }
 
   async updateProfile(userId: string, update: ProfileUpdate): Promise<void> {
@@ -146,6 +150,6 @@ export class PostgresProfileSettingsRepository implements ProfileSettingsReposit
   }
 
   async close(): Promise<void> {
-    await this.pool.end();
+    await closeResolvedPool(this.pool, this.ownsPool);
   }
 }

apps/api/src/index.ts

@@ -2,6 +2,7 @@ import { serve } from '@hono/node-server';
 import { createApp } from './app.js';
 import { createAuthVerifier } from './auth.js';
 import { loadConfig } from './config.js';
+import { createDatabasePool } from './db/pool.js';
 import { PostgresRepository } from './db/repository.js';
 import { PostgresAppDataRepository } from './domains/app-data/repository.js';
 import { AdminRequestAuth } from './domains/admin/auth.js';
@@ -26,30 +27,34 @@ import { FilesystemMediaStorage, PostgresMediaRepository } from './domains/media
 
 const config = loadConfig();
 const authVerifier = createAuthVerifier(config);
-const repository = new PostgresRepository(config.databaseUrl);
-const coupleRepository = new PostgresCoupleRepository(config.databaseUrl);
-const packsRepository = new PostgresPacksRepository(config.databaseUrl);
-const answersRepository = new PostgresAnswersRepository(config.databaseUrl);
-const chatRepository = new PostgresChatRepository(config.databaseUrl);
-const daresRepository = new PostgresDaresRepository(config.databaseUrl);
-const profileSettingsRepository = new PostgresProfileSettingsRepository(config.databaseUrl);
-const accountOperationsRepository = new PostgresAccountOperationsRepository(config.databaseUrl);
+// One deliberately bounded pool for the whole process. Repositories used to open
+// a default-sized pool each, so a single API instance could hold twelve times the
+// connections a self-hosted PostgreSQL was sized for.
+const pool = createDatabasePool(config.databaseUrl, config.databasePool);
+const repository = new PostgresRepository(pool);
+const coupleRepository = new PostgresCoupleRepository(pool);
+const packsRepository = new PostgresPacksRepository(pool);
+const answersRepository = new PostgresAnswersRepository(pool);
+const chatRepository = new PostgresChatRepository(pool);
+const daresRepository = new PostgresDaresRepository(pool);
+const profileSettingsRepository = new PostgresProfileSettingsRepository(pool);
+const accountOperationsRepository = new PostgresAccountOperationsRepository(pool);
 const accountOperationsService = new AccountOperationsService(
   accountOperationsRepository,
   new SupabaseAuthAdminClient(config.authIssuer, config.supabaseAuthServiceRoleKey),
   new HttpRevenueCatClient(config.revenueCatApiKey, config.revenueCatEntitlementId),
   new ExpoPartnerNotifier(),
 );
-const mediaRepository = new PostgresMediaRepository(config.databaseUrl);
+const mediaRepository = new PostgresMediaRepository(pool);
 const mediaStorage = new FilesystemMediaStorage(
   config.mediaRoot,
   config.mediaSigningSecret,
   config.mediaPublicBaseUrl,
 );
-const appDataRepository = new PostgresAppDataRepository(config.databaseUrl);
-const billingRepository = new PostgresBillingRepository(config.databaseUrl);
+const appDataRepository = new PostgresAppDataRepository(pool);
+const billingRepository = new PostgresBillingRepository(pool);
 const billingService = new BillingService(billingRepository, config.revenueCatWebhookSecret);
-const adminRepository = new PostgresAdminRepository(config.databaseUrl, {
+const adminRepository = new PostgresAdminRepository(pool, {
   adminPrivateKeyJwk: config.adminPrivateKeyJwk,
   mediaRoot: config.mediaRoot,
   authDirectory: new SupabaseAdminAuthDirectory(config.authIssuer, config.supabaseAuthServiceRoleKey),
@@ -94,20 +99,9 @@ async function shutdown(signal: string): Promise<void> {
 
   server.close(async () => {
     try {
-      await Promise.all([
-        repository.close(),
-        coupleRepository.close(),
-        packsRepository.close(),
-        answersRepository.close(),
-        chatRepository.close(),
-        daresRepository.close(),
-        profileSettingsRepository.close(),
-        accountOperationsRepository.close(),
-        mediaRepository.close(),
-        appDataRepository.close(),
-        billingRepository.close(),
-        adminRepository.close(),
-      ]);
+      // Repositories share the process pool and no longer own a connection each,
+      // so ending the pool once is the whole of the database shutdown.
+      await pool.end();
       process.exit(0);
     } catch (error) {
       console.error('Failed to close database connections', error);

apps/api/test/answers.integration.test.ts

@@ -6,7 +6,7 @@ import { PostgresAnswersRepository } from '../src/domains/answers/repository.js'
 const url=process.env.DATABASE_URL;const local=url?['127.0.0.1','localhost','::1'].includes(new URL(url).hostname):false;if(url&&!local)throw new Error('Answer integration tests only permit localhost');
 describe.skipIf(!url||!local)('answers + PostgreSQL',()=>{const admin=new Pool({connectionString:url});const schema=`answers_${randomUUID().replaceAll('-','')}`;let pool:Pool;let repo:PostgresAnswersRepository;
 const u1='11111111-1111-4111-8111-111111111111',u2='22222222-2222-4222-8222-222222222222',outsider='33333333-3333-4333-8333-333333333333',couple='44444444-4444-4444-8444-444444444444',other='55555555-5555-4555-8555-555555555555',pack='66666666-6666-4666-8666-666666666666',q='77777777-7777-4777-8777-777777777777',concurrentQ='88888888-8888-4888-8888-888888888888',femaleOnlyQ='99999999-9999-4999-8999-999999999999',limitQ1='aaaaaaaa-aaaa-4aaa-8aaa-aaaaaaaaaaaa',limitQ2='bbbbbbbb-bbbb-4bbb-8bbb-bbbbbbbbbbbb',catchUpQ='cccccccc-cccc-4ccc-8ccc-cccccccccccc';
-beforeAll(async()=>{await admin.query(`create schema "${schema}"`);const isolated=new URL(url!);isolated.searchParams.set('options',`-c search_path=${schema}`);pool=new Pool({connectionString:isolated.toString()});repo=new PostgresAnswersRepository(isolated.toString());for(const name of ['0000_identity_and_feature_interests.sql','0001_couples.sql','0002_packs_catalog_progress.sql','0003_answers_matches.sql','0014_daily_limit_local_reset.sql','0015_daily_limit_response_index.sql','0016_couple_streak_locality.sql']){const sql=await readFile(new URL(`../drizzle/${name}`,import.meta.url),'utf8');for(const s of sql.split('--> statement-breakpoint'))if(s.trim())await pool.query(s);}await pool.query('insert into couples(id,invite_code) values($1,$2),($3,$4)',[couple,'ANSWERS1',other,'ANSWERS2']);await pool.query("insert into profiles(id,couple_id,gender,max_intensity) values($1,$4,'female',5),($2,$4,'male',3),($3,$5,'male',5)",[u1,u2,outsider,couple,other]);await pool.query("insert into question_packs(id,name) values($1,'Core')",[pack]);await pool.query("insert into questions(id,pack_id,text,intensity,target_user_genders) values($1,$2,'Question',3,array['female']),($3,$2,'Concurrent',2,null),($4,$2,'Female first',2,array['female']),($5,$2,'Limit one',2,null),($6,$2,'Limit two',2,null),($7,$2,'Catch up',2,null)",[q,pack,concurrentQ,femaleOnlyQ,limitQ1,limitQ2,catchUpQ]);await pool.query('insert into couple_packs(couple_id,pack_id,enabled) values($1,$2,true)',[couple,pack]);});afterAll(async()=>{await repo.close();await pool.end();await admin.query(`drop schema "${schema}" cascade`);await admin.end();});
+beforeAll(async()=>{await admin.query(`create schema "${schema}"`);const isolated=new URL(url!);isolated.searchParams.set('options',`-c search_path=${schema}`);pool=new Pool({connectionString:isolated.toString()});repo=new PostgresAnswersRepository(isolated.toString());for(const name of ['0000_identity_and_feature_interests.sql','0001_couples.sql','0002_packs_catalog_progress.sql','0003_answers_matches.sql','0004_chat.sql','0014_daily_limit_local_reset.sql','0015_daily_limit_response_index.sql','0016_couple_streak_locality.sql']){const sql=await readFile(new URL(`../drizzle/${name}`,import.meta.url),'utf8');for(const s of sql.split('--> statement-breakpoint'))if(s.trim())await pool.query(s);}await pool.query('insert into couples(id,invite_code) values($1,$2),($3,$4)',[couple,'ANSWERS1',other,'ANSWERS2']);await pool.query("insert into profiles(id,couple_id,gender,max_intensity) values($1,$4,'female',5),($2,$4,'male',3),($3,$5,'male',5)",[u1,u2,outsider,couple,other]);await pool.query("insert into question_packs(id,name) values($1,'Core')",[pack]);await pool.query("insert into questions(id,pack_id,text,intensity,target_user_genders) values($1,$2,'Question',3,array['female']),($3,$2,'Concurrent',2,null),($4,$2,'Female first',2,array['female']),($5,$2,'Limit one',2,null),($6,$2,'Limit two',2,null),($7,$2,'Catch up',2,null)",[q,pack,concurrentQ,femaleOnlyQ,limitQ1,limitQ2,catchUpQ]);await pool.query('insert into couple_packs(couple_id,pack_id,enabled) values($1,$2,true)',[couple,pack]);});afterAll(async()=>{await repo.close();await pool.end();await admin.query(`drop schema "${schema}" cascade`);await admin.end();});
 it('targets recommendation by gender and excludes completed responses',async()=>{expect((await repo.recommended(u1)).map(x=>x.id)).toContain(q);expect((await repo.recommended(u2)).map(x=>x.id)).not.toContain(q);await repo.submit(u1,{questionId:q,answer:'yes'});expect((await repo.recommended(u1)).map(x=>x.id)).not.toContain(q);});
 it('rejects direct answers that bypass target-gender eligibility',async()=>{await expect(repo.submit(u2,{questionId:femaleOnlyQ,answer:'yes'})).rejects.toMatchObject({code:'question_not_eligible'});});
 it('serializes concurrent partner submissions and still creates one match',async()=>{await Promise.all([repo.submit(u1,{questionId:concurrentQ,answer:'yes'}),repo.submit(u2,{questionId:concurrentQ,answer:'yes'})]);const counts=await pool.query('select count(*)::int count from matches where question_id=$1',[concurrentQ]);expect(counts.rows[0].count).toBe(1);});
@@ -18,6 +18,71 @@ it('answers the streak from the caller side rather than by stored position',asyn
   expect(await repo.streak(u1)).toMatchObject({you_answered_today:true,partner_answered_today:false,partner_name:'Alex',current_streak:0});
   expect(await repo.streak(u2)).toMatchObject({you_answered_today:false,partner_answered_today:true,partner_name:'Sam',current_streak:0});});
 
+describe('match pagination',()=>{
+  const paged=Array.from({length:5},(_,index)=>`d0000000-0000-4000-8000-00000000000${index}`);
+  const pagedQuestions=Array.from({length:5},(_,index)=>`f0000000-0000-4000-8000-00000000000${index}`);
+  const otherMatch='e0000000-0000-4000-8000-000000000000';
+  beforeAll(async()=>{
+    await pool.query('delete from match_archives');await pool.query('delete from messages');await pool.query('delete from matches');
+    // One question per match: a couple may only match a given question once.
+    for(const[index,id]of pagedQuestions.entries())await pool.query("insert into questions(id,pack_id,text,intensity) values($1,$2,$3,2)",[id,pack,`Paged ${index}`]);
+    // Distinct creation times so the ordering assertion is about the query, not tie-breaking.
+    for(const[index,id]of paged.entries())await pool.query("insert into matches(id,couple_id,question_id,match_type,created_at) values($1,$2,$3,'yes_yes',now()-($4::text||' minutes')::interval)",[id,couple,pagedQuestions[index],String(index)]);
+    // A match belonging to another couple must never appear, whatever the page.
+    await pool.query("insert into matches(id,couple_id,question_id,match_type) values($1,$2,$3,'yes_yes')",[otherMatch,other,q]);
+    // Two unread from the partner on the oldest match; one message of our own, which is never unread.
+    await pool.query("insert into messages(match_id,user_id,content) values($1,$2,'a'),($1,$2,'b'),($1,$3,'mine')",[paged[4],u2,u1]);
+  });
+
+  it('counts once on the first page, never again, and still reports hasMore',async()=>{
+    const first=await repo.matches(u1,0,2,false);
+    expect(first.totalCount).toBe(5);
+    expect(first.hasMore).toBe(true);
+    expect(first.matches).toHaveLength(2);
+
+    // Later pages skip the count entirely: the client already has it and paging
+    // is decided by hasMore, which comes from reading limit + 1 rows.
+    const second=await repo.matches(u1,1,2,false);
+    expect(second.totalCount).toBeNull();
+    expect(second.hasMore).toBe(true);
+    const last=await repo.matches(u1,2,2,false);
+    expect(last.totalCount).toBeNull();
+    expect(last.hasMore).toBe(false);
+    expect(last.matches).toHaveLength(1);
+
+    // An exactly-full final page must not claim another page exists.
+    expect(await repo.matches(u1,0,5,false)).toMatchObject({hasMore:false,totalCount:5});
+  });
+
+  it('keeps unread-first ordering, aggregates unread once, and isolates the other couple',async()=>{
+    const page=await repo.matches(u1,0,5,false);
+    // The unread match sorts ahead of newer ones; the rest stay newest-first.
+    expect(page.matches.map(item=>item.id)).toEqual([paged[4],paged[0],paged[1],paged[2],paged[3]]);
+    expect(page.matches[0]).toMatchObject({unreadCount:2});
+    // Our own message is not unread to us, and everything else is zero.
+    expect(page.matches.slice(1).every(item=>item.unreadCount===0)).toBe(true);
+    // Unread is per viewer: the partner's own two messages are not unread to them,
+    // but ours is, so the same thread reports a different count on each side.
+    expect((await repo.matches(u2,0,5,false)).matches.find(item=>item.id===paged[4])?.unreadCount).toBe(1);
+    // The other couple's match is invisible here, and their member sees only theirs.
+    expect(page.matches.some(item=>item.id===otherMatch)).toBe(false);
+    expect((await repo.matches(outsider,0,5,false)).matches.map(item=>item.id)).toEqual([otherMatch]);
+  });
+
+  it('pages the archived view separately and per user',async()=>{
+    await repo.archive(u1,paged[0],true);
+    const active=await repo.matches(u1,0,5,false);
+    expect(active.matches.some(item=>item.id===paged[0])).toBe(false);
+    expect(active.totalCount).toBe(4);
+    const archived=await repo.matches(u1,0,5,true);
+    expect(archived.matches.map(item=>item.id)).toEqual([paged[0]]);
+    expect(archived).toMatchObject({totalCount:1,hasMore:false});
+    // Archiving is per user, so the partner still sees it in their active list.
+    expect((await repo.matches(u2,0,5,false)).matches.some(item=>item.id===paged[0])).toBe(true);
+    await repo.archive(u1,paged[0],false);
+  });
+});
+
 it('counts the day in the couple shared zone and prefers the first reported member zone',async()=>{await pool.query('update profiles set timezone=$2 where id=$1',[u1,'Pacific/Auckland']);await pool.query('update profiles set timezone=$2 where id=$1',[u2,'America/Los_Angeles']);
   await pool.query('delete from responses where couple_id=$1',[couple]);await pool.query('delete from matches where couple_id=$1',[couple]);
   await repo.submit(u1,{questionId:q,answer:'yes'});

apps/api/test/answers.routes.test.ts

@@ -10,7 +10,7 @@ const questionId='22222222-2222-4222-8222-222222222222';
 function repo():AnswersRepository{return {
   recommended:vi.fn(async()=>[]),pending:vi.fn(async()=>[]),answerGap:vi.fn(async()=>({unanswered_by_partner:0,threshold:10,is_blocked:false})),
   dailyLimit:vi.fn(async()=>({responses_today:0,limit_value:0,remaining:0,reset_at:null,is_blocked:false})),
-  submit:vi.fn(async()=>({response:{} as never,match:null})),update:vi.fn(async()=>({success:true})),responses:vi.fn(async()=>({responses:[],totalCount:0})),matches:vi.fn(async()=>({matches:[],totalCount:0})),markSeen:vi.fn(async()=>undefined),archive:vi.fn(async()=>undefined),streak:vi.fn(async()=>null),close:vi.fn(async()=>undefined)};}
+  submit:vi.fn(async()=>({response:{} as never,match:null})),update:vi.fn(async()=>({success:true})),responses:vi.fn(async()=>({responses:[],totalCount:0})),matches:vi.fn(async()=>({matches:[],totalCount:0,hasMore:false})),markSeen:vi.fn(async()=>undefined),archive:vi.fn(async()=>undefined),streak:vi.fn(async()=>null),close:vi.fn(async()=>undefined)};}
 function app(r:AnswersRepository){const app=new Hono<{Variables:{identity:AuthIdentity}}>();app.use('/v1/*',async(c,n)=>{c.set('identity',identity);await n();});registerAnswerRoutes(app,r);return app;}
 
 describe('answer routes',()=>{
@@ -18,6 +18,16 @@ describe('answer routes',()=>{
   it('maps confirmation and domain failures',async()=>{const r=repo();vi.mocked(r.update).mockResolvedValueOnce({success:false,requires_confirmation:true,message_count:2});const a=app(r);expect(await (await a.request(`/v1/responses/${questionId}`,{method:'PATCH',headers:{'content-type':'application/json'},body:'{"new_answer":"no"}'})).json()).toMatchObject({requires_confirmation:true,message_count:2});vi.mocked(r.submit).mockRejectedValueOnce(new AnswersError('daily_limit',429,'Daily response limit reached',{daily_limit:10,responses_today:10,remaining:0,reset_at:'2026-08-29T00:00:00.000Z'}));const blocked=await a.request('/v1/responses',{method:'POST',headers:{'content-type':'application/json'},body:JSON.stringify({question_id:questionId,answer:'yes'})});expect(blocked.status).toBe(429);
     // The client renders the limit screen straight from this body, so its shape is a contract.
     expect(await blocked.json()).toMatchObject({error:{code:'daily_limit'},details:{daily_limit:10,responses_today:10,remaining:0,reset_at:'2026-08-29T00:00:00.000Z'}});});
+  it('reports pagination from the repository, including a page with no total',async()=>{const r=repo();const a=app(r);
+    // Later pages skip the count entirely, so `hasMore` — not a client-side
+    // comparison against totalCount — is what decides whether to keep paging.
+    vi.mocked(r.matches).mockResolvedValueOnce({matches:[],totalCount:null,hasMore:true});
+    const later=await a.request('/v1/matches?page=2&limit=20');
+    expect(later.status).toBe(200);
+    expect(await later.json()).toMatchObject({totalCount:null,hasMore:true});
+    expect(r.matches).toHaveBeenCalledWith(identity.id,2,20,false);
+    await a.request('/v1/matches?page=0&limit=20&archived=true');
+    expect(r.matches).toHaveBeenLastCalledWith(identity.id,0,20,true);});
   it('scopes match mutations to identity',async()=>{const r=repo();const a=app(r);await a.request('/v1/matches/seen',{method:'PATCH',headers:{'content-type':'application/json'},body:JSON.stringify({ids:[questionId]})});expect(r.markSeen).toHaveBeenCalledWith(identity.id,[questionId]);await a.request(`/v1/matches/${questionId}/archive`,{method:'PUT',headers:{'content-type':'application/json'},body:'{"archived":true}'});expect(r.archive).toHaveBeenCalledWith(identity.id,questionId,true);});
 });
 

apps/api/test/api.integration.test.ts

@@ -75,6 +75,31 @@ describe.skipIf(!databaseUrl || !localDatabase)('API + PostgreSQL integration',
       },
     });
 
+    // Reading the profile again must not rewrite it. Every authenticated request the
+    // app makes starts here, so an unconditional upsert turned a read into a write
+    // on the busiest path in the API.
+    const stamps = async () => (await pool.query<{ auth_synced_at: Date | null; updated_at: Date }>(
+      'select auth_synced_at, updated_at from profiles where id = $1',
+      ['33333333-3333-4333-8333-333333333333'],
+    )).rows[0];
+    const created = await stamps();
+    expect(created.auth_synced_at).not.toBeNull();
+
+    for (let attempt = 0; attempt < 3; attempt += 1) {
+      expect((await app.request('/v1/me', { headers })).status).toBe(200);
+    }
+    const unchanged = await stamps();
+    expect(unchanged.auth_synced_at?.getTime()).toBe(created.auth_synced_at?.getTime());
+    expect(unchanged.updated_at.getTime()).toBe(created.updated_at.getTime());
+
+    // A genuine identity change still writes through, so first use and a changed
+    // email are both recorded rather than skipped.
+    await pool.query('update profiles set email = $2 where id = $1', ['33333333-3333-4333-8333-333333333333', 'stale@sauci.test']);
+    expect((await app.request('/v1/me', { headers })).status).toBe(200);
+    const resynced = await stamps();
+    expect(resynced.auth_synced_at!.getTime()).toBeGreaterThan(created.auth_synced_at!.getTime());
+    expect(await (await app.request('/v1/me', { headers })).json()).toMatchObject({ profile: { email: 'integration@sauci.test' } });
+
     expect((await app.request('/v1/me/feature-interests/better-chat', { method: 'PUT', headers })).status).toBe(200);
     expect(await (await app.request('/v1/me/feature-interests/better-chat', { headers })).json())
       .toEqual({ feature: 'better-chat', interested: true });

apps/api/test/app-data.integration.test.ts

@@ -30,6 +30,99 @@ describe.skipIf(!databaseUrl || !local)('app-data repository + PostgreSQL', () =
     await pool.query("insert into messages(id,match_id,user_id,media_path,media_type) values($1,$2,$3,'x.jpg','image')",[message,match,alice]);
   });
   afterAll(async()=>{await repo.close();await pool.end();await admin.query(`drop schema "${schema}" cascade`);await admin.end();});
+  it('summarises change markers per couple without leaking another couple state',async()=>{
+    // This one small read replaced a five-second refresh of profile, couple, matches,
+    // pending questions, packs and unread counts, so its markers have to move for
+    // exactly the changes those refreshes existed to notice.
+    const before=await repo.syncSummary(alice);
+    expect(before).toMatchObject({couple_id:couple,partner_id:bob,match_count:1,new_match_count:1,unread_total:0});
+    expect(before.profile_updated_at).not.toBeNull();
+    expect(Date.parse(before.server_time)).not.toBeNaN();
+
+    // The partner's own message is unread to them and not to us.
+    expect((await repo.syncSummary(bob)).unread_total).toBe(1);
+
+    // A partner profile edit moves the partner marker, which is what tells the
+    // client to re-read the couple rather than everything.
+    await pool.query("update profiles set name='Bobby', updated_at=now() where id=$1",[bob]);
+    const afterPartner=await repo.syncSummary(alice);
+    expect(Date.parse(afterPartner.partner_updated_at!)).toBeGreaterThan(Date.parse(before.partner_updated_at!));
+    expect(afterPartner.profile_updated_at).toBe(before.profile_updated_at);
+
+    // couple_packs carries no timestamp, so equal-and-opposite toggles have to be
+    // caught by a digest rather than a max(updated_at).
+    const emptyDigest=before.enabled_packs_fingerprint;
+    expect(emptyDigest).toEqual(expect.any(String));
+    await pool.query('insert into couple_packs(couple_id,pack_id,enabled) values($1,$2,true)',[couple,pack]);
+    const enabled=await repo.syncSummary(alice);
+    expect(enabled.enabled_packs_fingerprint).not.toBe(emptyDigest);
+    await pool.query('update couple_packs set enabled=false where couple_id=$1 and pack_id=$2',[couple,pack]);
+    expect((await repo.syncSummary(alice)).enabled_packs_fingerprint).toBe(emptyDigest);
+    // Toggling back must land on the same digest, so the client stops refetching.
+    await pool.query('update couple_packs set enabled=true where couple_id=$1 and pack_id=$2',[couple,pack]);
+    expect((await repo.syncSummary(alice)).enabled_packs_fingerprint).toBe(enabled.enabled_packs_fingerprint);
+
+    // An outsider's summary is about their own couple and never ours.
+    const other=await repo.syncSummary(outsider);
+    expect(other).toMatchObject({couple_id:otherCouple,partner_id:null,match_count:0,unread_total:0});
+  });
+
+  it('moves the match-state fingerprint on an in-place edit that the count and latest-at markers miss',async()=>{
+    // Editing an existing match's type/response summary (response editing) creates
+    // no new match and touches no created_at, so match_count/new_match_count/
+    // latest_match_at all hold steady; only the state fingerprint must move.
+    const before=await repo.syncSummary(alice);
+    await pool.query("update matches set match_type='yes_maybe', response_summary=$2 where id=$1",[match,JSON.stringify({edited:true})]);
+    const after=await repo.syncSummary(alice);
+    expect(after.match_count).toBe(before.match_count);
+    expect(after.new_match_count).toBe(before.new_match_count);
+    expect(after.latest_match_at).toBe(before.latest_match_at);
+    expect(after.match_state_fingerprint).not.toBe(before.match_state_fingerprint);
+    // Reverting lands back on the same digest, so the client stops refetching.
+    await pool.query("update matches set match_type='yes_yes', response_summary=null where id=$1",[match]);
+    expect((await repo.syncSummary(alice)).match_state_fingerprint).toBe(before.match_state_fingerprint);
+  });
+
+  it('moves the match-unread fingerprint when unread redistributes without changing the total',async()=>{
+    const secondMatch='cccccccc-cccc-4ccc-8ccc-cccccccccccc';
+    const secondQuestion='dddddddd-dddd-4ddd-8ddd-dddddddddddd';
+    const originalUnread='eeeeeeee-eeee-4eee-8eee-eeeeeeeeeeee';
+    const secondUnread='11111111-2222-4333-8444-555555555555';
+    await pool.query("insert into questions(id,pack_id,text) values($1,$2,'Question 2')",[secondQuestion,pack]);
+    await pool.query("insert into matches(id,couple_id,question_id,match_type) values($1,$2,$3,'yes_yes')",[secondMatch,couple,secondQuestion]);
+    // Alice's own message ('message', from beforeAll) is never unread to her, so
+    // give the original match a message from her partner to actually redistribute.
+    await pool.query("insert into messages(id,match_id,user_id,media_path,media_type) values($1,$2,$3,'y.jpg','image')",[originalUnread,match,bob]);
+    await pool.query("insert into messages(id,match_id,user_id,media_path,media_type) values($1,$2,$3,'y2.jpg','image')",[secondUnread,secondMatch,bob]);
+
+    const before=await repo.syncSummary(alice);
+    expect(before.unread_total).toBe(2);
+
+    // Read the original match's unread message while a new one lands in the
+    // second match: unread_total holds steady at 2, but which match owns it moves.
+    await pool.query('update messages set read_at=now() where id=$1',[originalUnread]);
+    const thirdMessage='ffffffff-ffff-4fff-8fff-ffffffffffff';
+    await pool.query("insert into messages(id,match_id,user_id,media_path,media_type) values($1,$2,$3,'z.jpg','image')",[thirdMessage,secondMatch,bob]);
+
+    const after=await repo.syncSummary(alice);
+    expect(after.unread_total).toBe(before.unread_total);
+    expect(after.match_unread_fingerprint).not.toBe(before.match_unread_fingerprint);
+
+    // Clean up so later assertions in this suite see the original single-match state.
+    await pool.query('delete from messages where id=any($1::uuid[])',[[originalUnread,secondUnread,thirdMessage]]);
+    await pool.query('delete from matches where id=$1',[secondMatch]);
+    await pool.query('delete from questions where id=$1',[secondQuestion]);
+  });
+
+  it('moves the streak marker from couple_streaks.updated_at',async()=>{
+    await pool.query('insert into couple_streaks(couple_id) values($1) on conflict do nothing',[couple]);
+    const before=await repo.syncSummary(alice);
+    expect(before.streak_updated_at).toEqual(expect.any(String));
+    await pool.query('update couple_streaks set current_streak=current_streak+1, updated_at=now() where couple_id=$1',[couple]);
+    const after=await repo.syncSummary(alice);
+    expect(Date.parse(after.streak_updated_at!)).toBeGreaterThan(Date.parse(before.streak_updated_at!));
+  });
+
   it('returns only public catalog data and couple-owned match context',async()=>{
     expect((await repo.packQuestions(alice,pack))[0]?.text).toBe('Question');
     expect((await repo.matchContext(bob,match)).responses).toHaveLength(2);

apps/api/test/app-data.routes.test.ts

@@ -16,6 +16,12 @@ function repository(): AppDataRepository {
     markMediaViewed: vi.fn(async () => ({ media_viewed_at: 'now', media_expires_at: null })),
     nudgeStatus: vi.fn(async () => ({ last_nudge_sent_at: null })),
     sendNudge: vi.fn(async () => ({ success: true as const, notification_sent: false, reason: 'no_push_token', next_nudge_available_at: 'later' })),
+    syncSummary: vi.fn(async () => ({
+      server_time: 'now', couple_id: null, profile_updated_at: null, partner_id: null, partner_updated_at: null,
+      match_count: 0, new_match_count: 0, latest_match_at: null, pending_yours: 0, pending_theirs: 0,
+      unread_total: 0, enabled_packs_fingerprint: '',
+      match_state_fingerprint: '', match_unread_fingerprint: '', streak_updated_at: null,
+    })),
     getLiveDraw: vi.fn(async () => ({ strokes: [], revision: 0, updated_at: null, updated_by: null })),
     putLiveDraw: vi.fn(async () => ({ strokes: [], revision: 1, updated_at: 'now', updated_by: identity.id })),
     close: vi.fn(async () => undefined),

apps/api/test/chat.integration.test.ts

@@ -48,7 +48,7 @@ describe.skipIf(!databaseUrl || !isLocal)('chat repository + PostgreSQL', () =>
 
   it('sends, lists, counts and reads text messages for couple members only', async () => {
     const sent = await repository.sendText(alice, match, 'Hello');
-    expect((await repository.listMessages(bob, match))[0]?.content).toBe('Hello');
+    expect((await repository.listMessages(bob, match)).messages[0]?.content).toBe('Hello');
     expect(await repository.unreadCounts(bob)).toEqual({ total: 1, by_match: { [match]: 1 } });
     expect((await repository.markDelivered(bob, sent.id)).delivered_at).not.toBeNull();
     expect((await repository.markMatchRead(bob, match)).updated).toBe(1);
@@ -58,14 +58,110 @@ describe.skipIf(!databaseUrl || !isLocal)('chat repository + PostgreSQL', () =>
   it('enforces per-user and author-only deletions plus reports', async () => {
     const sent = await repository.sendText(alice, match, 'Moderate me');
     await repository.deleteForSelf(bob, sent.id);
-    expect((await repository.listMessages(bob, match)).some(item => item.id === sent.id)).toBe(false);
-    expect((await repository.listMessages(alice, match)).some(item => item.id === sent.id)).toBe(true);
+    expect((await repository.listMessages(bob, match)).messages.some(item => item.id === sent.id)).toBe(false);
+    expect((await repository.listMessages(alice, match)).messages.some(item => item.id === sent.id)).toBe(true);
     await expect(repository.deleteForEveryone(bob, sent.id)).rejects.toMatchObject({ code: 'not_message_author' });
     expect((await repository.deleteForEveryone(alice, sent.id)).deleted_at).not.toBeNull();
     await repository.report(bob, sent.id, 'harassment');
     await expect(repository.report(bob, sent.id, 'spam')).rejects.toBeInstanceOf(ChatError);
   });
 
+  it('answers a delta with only what changed, and the same rows a full read would give', async () => {
+    const before = await repository.listMessages(bob, match);
+    const cursor = before.server_time;
+    expect(before.complete).toBe(true);
+
+    // Nothing has happened since the cursor, so the delta carries no row the client
+    // has not already seen. The cursor is deliberately held a couple of seconds
+    // behind wall clock so a write racing the read is repeated rather than lost;
+    // that repetition is absorbed by merging on id, never by blanking the thread.
+    const known = new Set(before.messages.map(item => item.id));
+    const quiet = await repository.listMessages(bob, match, { since: cursor });
+    expect(quiet.complete).toBe(false);
+    expect(quiet.messages.every(item => known.has(item.id))).toBe(true);
+    expect(quiet.removed_ids?.every(id => !known.has(id))).toBe(true);
+
+    const fresh = await repository.sendText(alice, match, 'Delta arrival');
+    const delta = await repository.listMessages(bob, match, { since: cursor });
+    expect(delta.messages.map(item => item.id)).toContain(fresh.id);
+    // Media and moderation columns must survive the narrower query.
+    expect(delta.messages.find(item => item.id === fresh.id)).toMatchObject({
+      content: 'Delta arrival', media_path: null, media_type: null, media_expired: false, read_at: null,
+    });
+
+    // A status change with no new row still reaches the sender through the delta.
+    const afterSend = await repository.listMessages(alice, match);
+    await repository.markMatchRead(bob, match);
+    const readDelta = await repository.listMessages(alice, match, { since: afterSend.server_time });
+    expect(readDelta.messages.find(item => item.id === fresh.id)?.read_at).not.toBeNull();
+
+    // So does a deletion, which arrives as a removal rather than a silent gap.
+    const doomed = await repository.sendText(alice, match, 'Delete me');
+    const beforeDelete = await repository.listMessages(bob, match);
+    await repository.deleteForSelf(bob, doomed.id);
+    const removal = await repository.listMessages(bob, match, { since: beforeDelete.server_time });
+    expect(removal.removed_ids).toContain(doomed.id);
+
+    // Ordering is the contract the screen renders against: newest first, both ways.
+    const full = await repository.listMessages(bob, match);
+    const timestamps = full.messages.map(item => Date.parse(item.created_at));
+    expect([...timestamps].sort((a, b) => b - a)).toEqual(timestamps);
+
+    // Access control is unchanged on the delta path.
+    await expect(repository.listMessages(outsider, match, { since: cursor })).rejects.toMatchObject({ code: 'match_not_found' });
+  });
+
+  it('surfaces an expiring video to a chat that is already open, and only in the window it expires', async () => {
+    // Expiry is the one visible change no write announces: the deadline simply
+    // passes. Backdated so neither `created_at` nor `media_viewed_at` can be what
+    // puts the row in a delta — only the deadline crossing may.
+    const video = await repository.sendText(alice, match, 'Sent a video');
+    await pool.query(
+      `update messages
+          set media_path = 'media:expiring', media_type = 'video',
+              moderation_status = 'safe', encrypted_content = 'cipher', encryption_iv = 'iv',
+              created_at = now() - interval '1 hour',
+              media_viewed_at = now() - interval '1 hour',
+              media_expires_at = now() + interval '1 hour'
+        where id = $1`,
+      [video.id],
+    );
+
+    const before = await repository.listMessages(bob, match);
+    expect(before.messages.find(item => item.id === video.id)).toMatchObject({ media_expired: false });
+
+    // A deadline still in the future is not a change, so the row is not re-sent on
+    // every poll until it arrives.
+    const quiet = await repository.listMessages(bob, match, { since: before.server_time });
+    expect(quiet.messages.some(item => item.id === video.id)).toBe(false);
+
+    // The deadline now falls inside this poll's window.
+    await pool.query(`update messages set media_expires_at = now() - interval '1 second' where id = $1`, [video.id]);
+    const delta = await repository.listMessages(bob, match, { since: before.server_time });
+    const expired = delta.messages.find(item => item.id === video.id);
+    // Media, encryption and moderation columns still arrive whole on the delta path.
+    expect(expired).toMatchObject({
+      media_expired: true, media_type: 'video', media_path: 'media:expiring',
+      moderation_status: 'safe', encrypted_content: 'cipher', encryption_iv: 'iv',
+    });
+    expect(expired?.media_expires_at).not.toBeNull();
+    expect(expired?.media_viewed_at).not.toBeNull();
+
+    // A full read agrees, so leaving and re-entering the chat shows the same thing.
+    expect((await repository.listMessages(bob, match)).messages.find(item => item.id === video.id))
+      .toMatchObject({ media_expired: true });
+  });
+
+  it('folds the partner typing check into the message read when asked', async () => {
+    await repository.setTyping(alice, match, 4_000);
+    const withTyping = await repository.listMessages(bob, match, { includeTyping: true });
+    expect(withTyping.typing?.typing).toBe(true);
+    // Own typing is never reflected back, so the sender does not see themselves.
+    expect((await repository.listMessages(alice, match, { includeTyping: true })).typing?.typing).toBe(false);
+    // And it stays absent unless requested, so the default read costs no extra work.
+    expect((await repository.listMessages(bob, match)).typing).toBeUndefined();
+  });
+
   it('stores typing state with a short expiry and exposes only the partner state', async () => {
     await repository.setTyping(alice, match, 4_000);
     expect((await repository.getPartnerTyping(bob, match)).typing).toBe(true);

apps/api/test/chat.routes.test.ts

@@ -11,7 +11,8 @@ const message = { id: messageId, match_id: matchId, user_id: identity.id, conten
 
 function setup() {
   const repository: ChatRepository = {
-    listMessages: vi.fn(async () => [message]), sendText: vi.fn(async () => message),
+    listMessages: vi.fn(async () => ({ messages: [message], removed_ids: [], server_time: new Date().toISOString(), complete: true })),
+    sendText: vi.fn(async () => message),
     unreadCounts: vi.fn(async () => ({ total: 1, by_match: { [matchId]: 1 } })),
     markMatchRead: vi.fn(async () => ({ updated: 1, read_at: new Date().toISOString() })),
     markDelivered: vi.fn(async () => message), deleteForSelf: vi.fn(async () => undefined),
@@ -43,6 +44,28 @@ describe('chat routes', () => {
     expect(repository.sendText).not.toHaveBeenCalled();
   });
 
+  it('passes a delta cursor and folded typing check through to the repository', async () => {
+    const { app, repository } = setup();
+    const since = '2026-08-28T10:00:00.000Z';
+    const delta = await app.request(`/v1/matches/${matchId}/messages?since=${encodeURIComponent(since)}&typing=true`);
+    expect(delta.status).toBe(200);
+    expect(repository.listMessages).toHaveBeenCalledWith(identity.id, matchId, { since, includeTyping: true });
+
+    // Omitting both keeps the full-snapshot contract the client had before.
+    const snapshot = await app.request(`/v1/matches/${matchId}/messages`);
+    expect(snapshot.status).toBe(200);
+    expect(await snapshot.json()).toMatchObject({ messages: [{ id: messageId }] });
+    expect(repository.listMessages).toHaveBeenLastCalledWith(identity.id, matchId, { includeTyping: false });
+  });
+
+  it('refuses a malformed cursor rather than silently reading everything', async () => {
+    const { app, repository } = setup();
+    const response = await app.request(`/v1/matches/${matchId}/messages?since=yesterday`);
+    expect(response.status).toBe(400);
+    expect(await response.json()).toMatchObject({ error: { code: 'invalid_since' } });
+    expect(repository.listMessages).not.toHaveBeenCalled();
+  });
+
   it('supports unread, typing, deletion and reporting actions', async () => {
     const { app, repository } = setup();
     expect((await app.request('/v1/chat/unread')).status).toBe(200);

apps/api/test/db.pool.test.ts

@@ -0,0 +1,49 @@
+import { Pool } from 'pg';
+import { afterEach, describe, expect, it, vi } from 'vitest';
+import {
+  DEFAULT_POOL_MAX,
+  closeResolvedPool,
+  createDatabasePool,
+  resolvePool,
+} from '../src/db/pool.js';
+
+const url = 'postgres://user:pass@127.0.0.1:5432/sauci_test';
+
+afterEach(() => vi.restoreAllMocks());
+
+describe('database pool', () => {
+  it('bounds the shared pool and only forwards timeouts that were configured', () => {
+    // A process-wide pool is the whole point of the change: an unbounded default
+    // multiplied by one pool per repository is what the self-hosted database had
+    // to absorb before.
+    const bounded = createDatabasePool(url, { max: 4, idleTimeoutMillis: 1_000, connectionTimeoutMillis: 2_000 });
+    expect(bounded.options.max).toBe(4);
+    expect(bounded.options.idleTimeoutMillis).toBe(1_000);
+    expect(bounded.options.connectionTimeoutMillis).toBe(2_000);
+
+    const defaults = createDatabasePool(url);
+    expect(defaults.options.max).toBe(DEFAULT_POOL_MAX);
+
+    return Promise.all([bounded.end(), defaults.end()]);
+  });
+
+  it('owns a pool it built from a URL and never ends one it was handed', async () => {
+    // Repositories in the API process share one pool, so closing any single
+    // repository must not take the connections out from under the others. Tests
+    // still construct from a URL and must be able to close what they created.
+    const owned = resolvePool(url);
+    expect(owned.owned).toBe(true);
+    const ownedEnd = vi.spyOn(owned.pool, 'end');
+    await closeResolvedPool(owned.pool, owned.owned);
+    expect(ownedEnd).toHaveBeenCalledTimes(1);
+
+    const shared = new Pool({ connectionString: url });
+    const borrowed = resolvePool(shared);
+    expect(borrowed.owned).toBe(false);
+    expect(borrowed.pool).toBe(shared);
+    const sharedEnd = vi.spyOn(shared, 'end');
+    await closeResolvedPool(borrowed.pool, borrowed.owned);
+    expect(sharedEnd).not.toHaveBeenCalled();
+    await shared.end();
+  });
+});

apps/mobile/app/(app)/_layout.tsx

@@ -3,11 +3,12 @@ import { Ionicons } from "@expo/vector-icons";
 import { View, ActivityIndicator, StyleSheet, Platform, Text, Pressable, Animated, AppState } from "react-native";
 import { BlurView } from "expo-blur";
 import { useEffect, useState, useCallback, useRef } from "react";
-import { useAuthStore, useMatchStore, useMessageStore, useSubscriptionStore, usePacksStore, useStreakStore } from "../../src/store";
+import { useAuthStore, useMatchStore, useMessageStore, useSubscriptionStore, useStreakStore } from "../../src/store";
 import { colors, radius, spacing, typography, shadows } from "../../src/theme";
 import { authClient } from "../../src/lib/authClient";
 import { isBiometricEnabled } from "../../src/lib/biometricAuth";
 import { checkAndRegisterPushToken } from "../../src/lib/notifications";
+import { useCoupleSync } from "../../src/hooks/useCoupleSync";
 import { syncBadgeCount } from "../../src/lib/badge";
 import { BiometricLockScreen } from "../../src/components/BiometricLockScreen";
 import { Events } from "../../src/lib/analytics";
@@ -59,9 +60,8 @@ export default function AppLayout() {
     const router = useRouter();
     const segments = useSegments();
     const { isAuthenticated, isLoading, user, signOut, updateLastActive } = useAuthStore();
-    const { newMatchesCount, pendingQuestions, fetchPendingQuestions, fetchMatches } = useMatchStore();
-    const { unreadCount, lastMessage, fetchUnreadCount, clearLastMessage } = useMessageStore();
-    const { fetchEnabledPacks } = usePacksStore();
+    const { newMatchesCount, pendingQuestions, matches, fetchPendingQuestions, fetchMatches } = useMatchStore();
+    const { unreadCount, lastMessage, clearLastMessage } = useMessageStore();
     const { initializeRevenueCat, refreshSubscriptionStatus } = useSubscriptionStore();
     const { fetchStreak } = useStreakStore();
     const messageToastAnim = useRef(new Animated.Value(-100)).current;
@@ -173,12 +173,8 @@ export default function AppLayout() {
         setIsLocked(false);
     }, []);
 
-    // Fetch unread message count on mount
-    useEffect(() => {
-        if (user?.id) {
-            fetchUnreadCount();
-        }
-    }, [user?.id, fetchUnreadCount]);
+    // The unread badge arrives with the first sync summary, so it needs no request
+    // of its own here.
 
     // Fetch streak data when user is in a couple
     useEffect(() => {
@@ -187,12 +183,15 @@ export default function AppLayout() {
         }
     }, [user?.couple_id, fetchStreak]);
 
-    // Fetch pending questions (Your Turn) when user is in a couple
+    // Fetch pending questions (Your Turn) and matches when user is in a couple.
+    // Both feed tab badges, so they load once here and are kept current by the
+    // sync summary rather than by re-fetching on a timer.
     useEffect(() => {
         if (user?.couple_id) {
-            fetchPendingQuestions();
+            void fetchPendingQuestions();
+            void fetchMatches(true);
         }
-    }, [user?.couple_id, fetchPendingQuestions]);
+    }, [user?.couple_id, fetchPendingQuestions, fetchMatches]);
 
     // Sync app icon badge count whenever matches, messages, or pending questions change
     useEffect(() => {
@@ -214,44 +213,31 @@ export default function AppLayout() {
         }
     }, [user?.id, user?.onboarding_completed]);
 
-    // Poll the self-hosted API for profile, match, pending-question and pack changes.
-    // This replaces the former Supabase Postgres change subscriptions.
+    // One small change summary drives every domain refresh. It replaces a
+    // five-second refetch of profile, matches, pending questions and packs plus a
+    // three-second unread poll, and only asks a store to reload when the server
+    // reports that its data actually moved.
+    useCoupleSync(user?.id, user?.couple_id);
+
+    // Match analytics are derived from the store rather than from a poll response,
+    // so they fire once per genuinely new match however it arrived.
     useEffect(() => {
-        if (!user?.id) return;
-        let cancelled = false;
         matchPollInitializedRef.current = false;
         knownMatchIdsRef.current = new Set();
+    }, [user?.id, user?.couple_id]);
 
-        const poll = async () => {
-            await Promise.allSettled([
-                useAuthStore.getState().fetchUser(),
-                ...(user.couple_id ? [fetchMatches(true), fetchPendingQuestions(), fetchEnabledPacks()] : []),
-            ]);
-            if (cancelled || !user.couple_id) return;
-            const refreshed = useMatchStore.getState().matches;
-            if (matchPollInitializedRef.current) {
-                const added = refreshed.filter(item => !knownMatchIdsRef.current.has(item.id));
-                for (const item of added) Events.matchCreated(item.match_type || "unknown");
-                const previousCount = knownMatchIdsRef.current.size;
-                if (previousCount === 0 && added.length > 0) Events.firstMatch();
-                else if (added.length > 0 && refreshed.length % 10 === 0) Events.milestoneMatch(refreshed.length);
-            }
-            knownMatchIdsRef.current = new Set(refreshed.map(item => item.id));
-            matchPollInitializedRef.current = true;
-        };
-
-        void poll();
-        const timer = setInterval(() => void poll(), 5_000);
-        return () => { cancelled = true; clearInterval(timer); };
-    }, [user?.id, user?.couple_id, fetchMatches, fetchPendingQuestions, fetchEnabledPacks]);
-
-    // Poll the self-hosted API for unread chat state. Chat screens perform their
-    // own message polling; this keeps the global badge current without Supabase Realtime.
     useEffect(() => {
         if (!user?.couple_id) return;
-        const timer = setInterval(() => void fetchUnreadCount(), 3_000);
-        return () => clearInterval(timer);
-    }, [user?.couple_id, fetchUnreadCount]);
+        const known = knownMatchIdsRef.current;
+        const added = matches.filter(item => !known.has(item.id));
+        if (matchPollInitializedRef.current && added.length > 0) {
+            for (const item of added) Events.matchCreated(item.match_type || "unknown");
+            if (known.size === 0) Events.firstMatch();
+            else if (matches.length % 10 === 0) Events.milestoneMatch(matches.length);
+        }
+        knownMatchIdsRef.current = new Set(matches.map(item => item.id));
+        matchPollInitializedRef.current = true;
+    }, [matches, user?.couple_id]);
 
     // Animate message toast when lastMessage changes
     useEffect(() => {

apps/mobile/app/(app)/index.tsx

@@ -4,7 +4,7 @@ import { useFocusEffect } from 'expo-router';
 import Animated, { FadeInDown } from 'react-native-reanimated';
 import { Ionicons } from '@expo/vector-icons';
 import { BlurView } from 'expo-blur';
-import { useAuthStore, usePacksStore, useStreakStore, useSubscriptionStore } from '../../src/store';
+import { useAuthStore, usePacksStore, useSubscriptionStore } from '../../src/store';
 import { GradientBackground } from '../../src/components/ui';
 import { Paywall } from '../../src/components/paywall';
 import { CompactHeader, ContentRow, DaresTile, LiveDrawTile } from '../../src/components/discovery';
@@ -68,8 +68,7 @@ function groupPacksByCategory(
 
 export default function DiscoveryScreen() {
   const { user, partner, couple } = useAuthStore();
-  const { packs, categories, fetchPacks, getPackProgress } = usePacksStore();
-  const { fetchStreak } = useStreakStore();
+  const { packs, categories, fetchPacks, ensurePacksLoaded, getPackProgress } = usePacksStore();
   const { subscription } = useSubscriptionStore();
   const { width } = useWindowDimensions();
   const [showPaywall, setShowPaywall] = useState(false);
@@ -79,12 +78,13 @@ export default function DiscoveryScreen() {
   const isPremiumUser = user?.is_premium || partner?.is_premium || subscription.isProUser;
   const isWideScreen = width > MAX_CONTENT_WIDTH;
 
-  // Refresh data when screen gains focus
+  // Load the catalog once. Returning to this tab shows what is cached; answering a
+  // question invalidates it, and StreakDisplay owns the streak, so neither needs a
+  // request here.
   useFocusEffect(
     useCallback(() => {
-      fetchPacks();
-      fetchStreak();
-    }, [fetchStreak])
+      void ensurePacksLoaded();
+    }, [ensurePacksLoaded])
   );
 
   // Group packs by category

apps/mobile/app/(app)/matches.tsx

@@ -39,6 +39,7 @@ export default function MatchesScreen() {
         fetchMatches,
         markAllAsSeen,
         isLoading,
+        isRefreshing,
         hasMore,
         isLoadingMore,
         totalCount,
@@ -58,7 +59,9 @@ export default function MatchesScreen() {
         fetchTheirTurnQuestions,
         currentView,
         setCurrentView,
+        ensureViewLoaded,
         fetchPendingQuestions,
+        fetchArchivedMatches,
         // Nudge state and methods
         nudgeCooldownUntil,
         isNudging,
@@ -118,14 +121,12 @@ export default function MatchesScreen() {
         setShowTutorial(false);
     };
 
+    // Load whichever view is showing, once. Returning to this tab reuses what is
+    // already cached; the sync poll refreshes it when the server reports a change,
+    // and pull-to-refresh remains the explicit way to force one.
     useFocusEffect(
         useCallback(() => {
-            fetchMatches(true);
-            // Also refresh pending questions when focused
-            fetchPendingQuestions();
-            fetchTheirTurnQuestions();
-            // Check nudge cooldown
-            checkNudgeCooldown();
+            ensureViewLoaded();
 
             // Cleanup: mark matches as seen when leaving the screen (if on Complete tab)
             return () => {
@@ -134,9 +135,15 @@ export default function MatchesScreen() {
                     state.markAllAsSeen();
                 }
             };
-        }, [])
+        }, [ensureViewLoaded])
     );
 
+    // The nudge cooldown only moves when this device sends a nudge, and sendNudge
+    // already records the new cooldown, so one read on mount is enough.
+    useEffect(() => {
+        void checkNudgeCooldown();
+    }, [checkNudgeCooldown]);
+
     // Format cooldown remaining time
     const formatCooldownTime = (cooldownUntil: Date): string => {
         const now = new Date();
@@ -633,13 +640,16 @@ export default function MatchesScreen() {
                                 refreshing={
                                     currentView === 'pending' ? isLoadingPending :
                                     currentView === 'their_turn' ? isLoadingTheirTurn :
-                                    isLoading
+                                    currentView === 'archived' ? isLoadingArchived :
+                                    isRefreshing
                                 }
                                 onRefresh={() => {
                                     if (currentView === 'pending') {
                                         fetchPendingQuestions();
                                     } else if (currentView === 'their_turn') {
                                         fetchTheirTurnQuestions();
+                                    } else if (currentView === 'archived') {
+                                        fetchArchivedMatches();
                                     } else {
                                         fetchMatches(true);
                                     }

apps/mobile/app/(app)/my-answers.tsx

@@ -47,7 +47,7 @@ const AnimatedSectionList = Animated.createAnimatedComponent(SectionList);
 type GroupByOption = "pack" | "date" | "answer";
 
 export default function MyAnswersScreen() {
-    const { responses, isLoading, isLoadingMore, hasMore, groupBy, dateSortOrder, fetchResponses, setGroupBy, toggleDateSortOrder, totalCount } = useResponsesStore();
+    const { responses, isLoading, isRefreshing, isLoadingMore, hasMore, groupBy, dateSortOrder, fetchResponses, ensureResponsesLoaded, setGroupBy, toggleDateSortOrder, totalCount } = useResponsesStore();
     const { user, partner } = useAuthStore();
     const router = useRouter();
     const params = useLocalSearchParams();
@@ -110,11 +110,12 @@ export default function MyAnswersScreen() {
     // Ambient orb breathing animations
     const { orbStyle1, orbStyle2 } = useAmbientOrbAnimation();
 
-    // Fetch responses on focus
+    // Load once, then keep showing what is cached. Answering or editing a response
+    // invalidates it, and pull-to-refresh is always available.
     useFocusEffect(
         useCallback(() => {
-            fetchResponses(true);
-        }, [])
+            void ensureResponsesLoaded();
+        }, [ensureResponsesLoaded])
     );
 
     const handleLoadMore = useCallback(() => {
@@ -271,7 +272,7 @@ export default function MyAnswersScreen() {
                         scrollEventThrottle={16}
                         refreshControl={
                             <RefreshControl
-                                refreshing={isLoading}
+                                refreshing={isRefreshing}
                                 onRefresh={() => fetchResponses(true)}
                                 tintColor={colors.primary}
                                 colors={[colors.primary]}

apps/mobile/app/pack/[id].tsx

@@ -44,7 +44,7 @@ const AnimatedFlatList = Animated.createAnimatedComponent(FlatList<Question>);
 export default function PackDetailsScreen() {
     const { id } = useLocalSearchParams();
     const router = useRouter();
-    const { packs, fetchPacks } = usePacksStore();
+    const { packs, ensurePacksLoaded } = usePacksStore();
     const { subscription } = useSubscriptionStore();
     const { user, partner } = useAuthStore();
     const [questions, setQuestions] = useState<Question[]>([]);
@@ -61,9 +61,7 @@ export default function PackDetailsScreen() {
     const category = categories.find(c => c.id === pack?.category_id);
 
     useEffect(() => {
-        if (packs.length === 0) {
-            fetchPacks();
-        }
+        void ensurePacksLoaded();
         fetchPackDetails();
     }, [id]);
 

apps/mobile/src/__tests__/features/swipe/useSwipeScreen.test.ts

@@ -17,13 +17,19 @@ jest.mock("expo-router", () => ({
 jest.mock("@/store", () => {
     const auth = { user: { id: "user-1" }, partner: { id: "user-2" }, couple: { id: "couple-1", couple_id: "couple-1" } };
     const packs = { enabledPackIds: ["pack-1"], ensureEnabledPacksLoaded: async () => undefined, packs: [] };
+    const packState = { ...packs, invalidatePacks: jest.fn() };
+    const responses = { invalidateResponses: jest.fn() };
     const useAuthStore = () => auth;
     useAuthStore.getState = () => auth.user;
+    const usePacksStore = () => packs;
+    usePacksStore.getState = () => packState;
+    const useResponsesStore = () => responses;
+    useResponsesStore.getState = () => responses;
     // Read lazily: the factory runs before this module's own consts are initialised.
     const streak = { fetchStreak: () => mockFetchStreak() };
     const useStreakStore = () => streak;
     useStreakStore.getState = () => streak;
-    return { useAuthStore, usePacksStore: () => packs, useStreakStore };
+    return { useAuthStore, usePacksStore, useResponsesStore, useStreakStore };
 });
 
 jest.mock("@/lib/skippedQuestions", () => ({
@@ -45,17 +51,19 @@ const questions = [
     { id: "q2", pack_id: "pack-1", question_type: "swipe", text: "Two" },
 ];
 
+const futureResetAt = "2099-08-29T00:00:00.000Z";
+
 const openLimit = {
     responses_today: 4,
     limit_value: 10,
     remaining: 6,
-    reset_at: "2026-08-29T00:00:00.000Z",
+    reset_at: futureResetAt,
     is_blocked: false,
 };
 
 const dailyLimit429 = () => new ApiError("Daily response limit reached", 429, {
     error: { code: "daily_limit", message: "Daily response limit reached" },
-    details: { daily_limit: 10, responses_today: 10, remaining: 0, reset_at: "2026-08-29T00:00:00.000Z" },
+    details: { daily_limit: 10, responses_today: 10, remaining: 0, reset_at: futureResetAt },
 });
 
 // clearMocks wipes implementations between tests, so re-arm the whole surface each time.
@@ -92,7 +100,7 @@ describe("useSwipeScreen daily limit", () => {
             responses_today: 10,
             limit_value: 10,
             remaining: 0,
-            reset_at: "2026-08-29T00:00:00.000Z",
+            reset_at: futureResetAt,
             is_blocked: true,
         });
     });

apps/mobile/src/__tests__/hooks/useCoupleSync.test.ts

@@ -0,0 +1,313 @@
+import { act, renderHook } from '@testing-library/react-native';
+import { useCoupleSync, SYNC_INTERVAL_MS } from '@/hooks/useCoupleSync';
+import { appDataApi, type SyncSummary } from '@/lib/appDataApi';
+import { useAuthStore } from '@/store/authStore';
+import { useMatchStore } from '@/store/matchStore';
+import { useMessageStore } from '@/store/messageStore';
+import { usePacksStore } from '@/store/packsStore';
+import { useStreakStore } from '@/store/streakStore';
+
+jest.mock('@/lib/appDataApi', () => ({ appDataApi: { syncSummary: jest.fn() } }));
+
+const mockForeground = { value: true };
+const mockListeners = new Set<(foreground: boolean) => void>();
+jest.mock('@/lib/appForeground', () => ({
+    isForeground: () => mockForeground.value,
+    subscribeToForeground: (listener: (foreground: boolean) => void) => {
+        mockListeners.add(listener);
+        return () => { mockListeners.delete(listener); };
+    },
+}));
+
+const baseline: SyncSummary = {
+    server_time: '2026-08-27T12:00:00.000Z',
+    couple_id: 'couple',
+    profile_updated_at: '2026-08-01T00:00:00.000Z',
+    partner_id: 'partner',
+    partner_updated_at: '2026-08-01T00:00:00.000Z',
+    match_count: 3,
+    new_match_count: 0,
+    latest_match_at: '2026-08-20T00:00:00.000Z',
+    pending_yours: 1,
+    pending_theirs: 2,
+    unread_total: 0,
+    enabled_packs_fingerprint: 'digest-a',
+    match_state_fingerprint: 'state-a',
+    match_unread_fingerprint: 'unread-a',
+    streak_updated_at: '2026-08-01T00:00:00.000Z',
+};
+
+const flush = async () => { await act(async () => { await Promise.resolve(); await Promise.resolve(); }); };
+const tick = async () => {
+    await flush();
+    await act(async () => { jest.advanceTimersByTime(SYNC_INTERVAL_MS); });
+    await flush();
+};
+
+/** Replaces every domain refresh the sync can dispatch with a counter. */
+function stubRefreshers() {
+    const fetchUser = jest.fn(async () => undefined);
+    const fetchCouple = jest.fn(async () => undefined);
+    const fetchMatches = jest.fn(async () => undefined);
+    const fetchPendingQuestions = jest.fn(async () => undefined);
+    const fetchTheirTurnQuestions = jest.fn(async () => undefined);
+    const fetchEnabledPacks = jest.fn(async () => undefined);
+    const refreshStreak = jest.fn(async () => undefined);
+    useAuthStore.setState({ fetchUser, fetchCouple } as never);
+    useMatchStore.setState({ fetchMatches, fetchPendingQuestions, fetchTheirTurnQuestions } as never);
+    usePacksStore.setState({ fetchEnabledPacks } as never);
+    useStreakStore.setState({ refreshStreak } as never);
+    return { fetchUser, fetchCouple, fetchMatches, fetchPendingQuestions, fetchTheirTurnQuestions, fetchEnabledPacks, refreshStreak };
+}
+
+describe('useCoupleSync', () => {
+    let refreshers: ReturnType<typeof stubRefreshers>;
+    const originals = {
+        auth: { fetchUser: useAuthStore.getState().fetchUser, fetchCouple: useAuthStore.getState().fetchCouple },
+        match: {
+            fetchMatches: useMatchStore.getState().fetchMatches,
+            fetchPendingQuestions: useMatchStore.getState().fetchPendingQuestions,
+            fetchTheirTurnQuestions: useMatchStore.getState().fetchTheirTurnQuestions,
+        },
+        packs: { fetchEnabledPacks: usePacksStore.getState().fetchEnabledPacks },
+        streak: { refreshStreak: useStreakStore.getState().refreshStreak },
+    };
+
+    beforeEach(() => {
+        jest.clearAllMocks();
+        jest.useFakeTimers();
+        mockForeground.value = true;
+        mockListeners.clear();
+        useMessageStore.setState({ unreadCount: 0 });
+        // Every view starts loaded: this hook must refresh only what is on screen,
+        // and the "not loaded" case is asserted separately below.
+        useMatchStore.setState({ loadedAt: { active: 1, pending: 1, their_turn: 1 } });
+        usePacksStore.setState({ enabledPacksLoadedAt: Date.now() });
+        refreshers = stubRefreshers();
+    });
+    afterEach(() => {
+        jest.useRealTimers();
+        useAuthStore.setState(originals.auth as never);
+        useMatchStore.setState({ ...originals.match, loadedAt: {} } as never);
+        usePacksStore.setState({ ...originals.packs, enabledPacksLoadedAt: null } as never);
+        useStreakStore.setState(originals.streak as never);
+    });
+
+    const answer = (...summaries: SyncSummary[]) => {
+        const mock = appDataApi.syncSummary as jest.Mock;
+        mock.mockReset();
+        for (const summary of summaries) mock.mockResolvedValueOnce(summary);
+        mock.mockResolvedValue(summaries[summaries.length - 1]);
+    };
+
+    it('spends one request per interval and refreshes nothing while the markers hold still', async () => {
+        answer(baseline);
+        renderHook(() => useCoupleSync('me', 'couple'));
+        await flush();
+        expect(appDataApi.syncSummary).toHaveBeenCalledTimes(1);
+
+        await tick();
+        await tick();
+        expect(appDataApi.syncSummary).toHaveBeenCalledTimes(3);
+        // Three polls, three requests in total: the baseline poll must not trigger
+        // the refresh of five domains that the old five-second sweep performed.
+        for (const refresh of Object.values(refreshers)) expect(refresh).not.toHaveBeenCalled();
+    });
+
+    it('applies the unread total from the summary without a second request', async () => {
+        answer(baseline, { ...baseline, unread_total: 4 });
+        renderHook(() => useCoupleSync('me', 'couple'));
+        await flush();
+        await tick();
+        expect(useMessageStore.getState().unreadCount).toBe(4);
+    });
+
+    it('refreshes only the domain whose marker moved', async () => {
+        answer(baseline, { ...baseline, latest_match_at: '2026-08-28T00:00:00.000Z', match_count: 4 });
+        renderHook(() => useCoupleSync('me', 'couple'));
+        await flush();
+        await tick();
+        expect(refreshers.fetchMatches).toHaveBeenCalledWith(true, { silent: true });
+        expect(refreshers.fetchPendingQuestions).not.toHaveBeenCalled();
+        expect(refreshers.fetchTheirTurnQuestions).not.toHaveBeenCalled();
+        expect(refreshers.fetchEnabledPacks).not.toHaveBeenCalled();
+        expect(refreshers.fetchUser).not.toHaveBeenCalled();
+        expect(refreshers.fetchCouple).not.toHaveBeenCalled();
+    });
+
+    it('routes each remaining marker to its own domain', async () => {
+        answer(baseline, {
+            ...baseline,
+            pending_yours: 2,
+            pending_theirs: 3,
+            enabled_packs_fingerprint: 'digest-b',
+            partner_updated_at: '2026-08-29T00:00:00.000Z',
+            streak_updated_at: '2026-08-29T00:00:00.000Z',
+        });
+        renderHook(() => useCoupleSync('me', 'couple'));
+        await flush();
+        await tick();
+        expect(refreshers.fetchPendingQuestions).toHaveBeenCalledWith({ silent: true });
+        expect(refreshers.fetchTheirTurnQuestions).toHaveBeenCalledWith({ silent: true });
+        expect(refreshers.fetchEnabledPacks).toHaveBeenCalledTimes(1);
+        expect(refreshers.refreshStreak).toHaveBeenCalledTimes(1);
+        // A partner profile change is a couple-level read; the whole user is only
+        // re-read when the user's own profile or couple membership moved.
+        expect(refreshers.fetchCouple).toHaveBeenCalledTimes(1);
+        expect(refreshers.fetchUser).not.toHaveBeenCalled();
+        expect(refreshers.fetchMatches).not.toHaveBeenCalled();
+    });
+
+    it('refreshes a loaded Matches view when the match-state fingerprint moves in place', async () => {
+        // Counts and latest-created-at do not move for an in-place match_type/
+        // response_summary edit; only the state fingerprint does.
+        answer(baseline, { ...baseline, match_state_fingerprint: 'state-b' });
+        renderHook(() => useCoupleSync('me', 'couple'));
+        await flush();
+        await tick();
+        expect(refreshers.fetchMatches).toHaveBeenCalledWith(true, { silent: true });
+    });
+
+    it('refreshes a loaded Matches view when unread redistributes without changing the total', async () => {
+        // One match is read while another receives a message: unread_total holds
+        // steady but the per-match fingerprint (and unread-first ordering) moves.
+        answer(baseline, { ...baseline, unread_total: baseline.unread_total, match_unread_fingerprint: 'unread-b' });
+        renderHook(() => useCoupleSync('me', 'couple'));
+        await flush();
+        await tick();
+        expect(refreshers.fetchMatches).toHaveBeenCalledWith(true, { silent: true });
+    });
+
+    it('does not refresh enabled packs when that domain has never been opened', async () => {
+        usePacksStore.setState({ enabledPacksLoadedAt: null });
+        answer(baseline, { ...baseline, enabled_packs_fingerprint: 'digest-b' });
+        renderHook(() => useCoupleSync('me', 'couple'));
+        await flush();
+        await tick();
+        expect(refreshers.fetchEnabledPacks).not.toHaveBeenCalled();
+    });
+
+    it('resets the baseline when the account identity changes, instead of diffing against the prior account', async () => {
+        answer({ ...baseline, match_count: 3 });
+        const { rerender } = renderHook(
+            ({ userId, coupleId }: { userId: string; coupleId: string }) => useCoupleSync(userId, coupleId),
+            { initialProps: { userId: 'alice', coupleId: 'couple-a' } },
+        );
+        await flush();
+        await tick(); // establishes alice's baseline (match_count: 3)
+
+        // Switch accounts: bob's couple has a completely different match_count.
+        // Without a baseline reset this would look like a 12-count jump and
+        // trigger a refresh purely from comparing across accounts.
+        answer({ ...baseline, couple_id: 'couple-b', match_count: 15 });
+        rerender({ userId: 'bob', coupleId: 'couple-b' });
+        await flush();
+        expect(refreshers.fetchMatches).not.toHaveBeenCalled();
+
+        await tick();
+        expect(refreshers.fetchMatches).not.toHaveBeenCalled();
+    });
+
+    it('re-reads the user once when the profile moves, instead of the couple as well', async () => {
+        answer(baseline, {
+            ...baseline,
+            profile_updated_at: '2026-08-29T00:00:00.000Z',
+            partner_updated_at: '2026-08-29T00:00:00.000Z',
+        });
+        renderHook(() => useCoupleSync('me', 'couple'));
+        await flush();
+        await tick();
+        expect(refreshers.fetchUser).toHaveBeenCalledTimes(1);
+        expect(refreshers.fetchCouple).not.toHaveBeenCalled();
+    });
+
+    it('leaves views the user has never opened unloaded', async () => {
+        useMatchStore.setState({ loadedAt: {} });
+        answer(baseline, {
+            ...baseline,
+            match_count: 9,
+            latest_match_at: '2026-08-29T00:00:00.000Z',
+            pending_yours: 7,
+            pending_theirs: 8,
+        });
+        renderHook(() => useCoupleSync('me', 'couple'));
+        await flush();
+        await tick();
+        expect(refreshers.fetchMatches).not.toHaveBeenCalled();
+        expect(refreshers.fetchPendingQuestions).not.toHaveBeenCalled();
+        expect(refreshers.fetchTheirTurnQuestions).not.toHaveBeenCalled();
+    });
+
+    it('stops entirely for a signed-out user and while the app is backgrounded', async () => {
+        answer(baseline);
+        const { unmount } = renderHook(() => useCoupleSync(undefined, null));
+        await flush();
+        await tick();
+        expect(appDataApi.syncSummary).not.toHaveBeenCalled();
+        unmount();
+
+        renderHook(() => useCoupleSync('me', 'couple'));
+        await flush();
+        expect(appDataApi.syncSummary).toHaveBeenCalledTimes(1);
+
+        await act(async () => {
+            mockForeground.value = false;
+            for (const listener of [...mockListeners]) listener(false);
+        });
+        await tick();
+        await tick();
+        expect(appDataApi.syncSummary).toHaveBeenCalledTimes(1);
+    });
+
+    it('discards a summary that lands after the account it belongs to was switched away', async () => {
+        // Alice's poll is still open when Bob signs in. Its answer describes a
+        // couple Bob is not in, so none of it may land: not his badge, not the
+        // baseline his next poll is diffed against, not a refresh decision.
+        let answerAlice: (summary: SyncSummary) => void = () => undefined;
+        const mock = appDataApi.syncSummary as jest.Mock;
+        mock.mockReset();
+        mock.mockReturnValueOnce(new Promise<SyncSummary>(resolve => { answerAlice = resolve; }));
+
+        const { rerender } = renderHook(
+            ({ userId, coupleId }: { userId: string; coupleId: string }) => useCoupleSync(userId, coupleId),
+            { initialProps: { userId: 'alice', coupleId: 'couple-a' } },
+        );
+        await flush();
+        expect(mock).toHaveBeenCalledTimes(1);
+
+        const bobBaseline: SyncSummary = { ...baseline, couple_id: 'couple-b', unread_total: 1, match_count: 2 };
+        mock.mockResolvedValue(bobBaseline);
+        rerender({ userId: 'bob', coupleId: 'couple-b' });
+        await flush();
+        expect(useMessageStore.getState().unreadCount).toBe(1);
+
+        // Alice's request finally answers, long after she stopped being the user.
+        await act(async () => {
+            answerAlice({ ...baseline, couple_id: 'couple-a', unread_total: 9, match_count: 42 });
+            await Promise.resolve();
+        });
+        await flush();
+        expect(useMessageStore.getState().unreadCount).toBe(1);
+
+        // Bob's baseline is still Bob's: a poll identical to his own first one has
+        // nothing to refresh. Had Alice's answer been recorded as the baseline,
+        // this would read as a 40-match jump and refresh the Matches view.
+        await tick();
+        expect(useMessageStore.getState().unreadCount).toBe(1);
+        for (const refresh of Object.values(refreshers)) expect(refresh).not.toHaveBeenCalled();
+    });
+
+    it('never runs two summaries at once', async () => {
+        let release: (summary: SyncSummary) => void = () => undefined;
+        (appDataApi.syncSummary as jest.Mock).mockReset();
+        (appDataApi.syncSummary as jest.Mock).mockReturnValueOnce(new Promise(resolve => { release = resolve; }));
+        (appDataApi.syncSummary as jest.Mock).mockResolvedValue(baseline);
+        renderHook(() => useCoupleSync('me', 'couple'));
+        await flush();
+        await act(async () => { jest.advanceTimersByTime(SYNC_INTERVAL_MS * 4); });
+        expect(appDataApi.syncSummary).toHaveBeenCalledTimes(1);
+        await act(async () => { release(baseline); await Promise.resolve(); });
+        await tick();
+        expect(appDataApi.syncSummary).toHaveBeenCalledTimes(2);
+    });
+});

apps/mobile/src/__tests__/hooks/useDares.test.ts

@@ -1,6 +1,7 @@
 import { act, renderHook, waitFor } from "@testing-library/react-native";
 import { useDares } from "@/features/dares/hooks/useDares";
 import { ApiError, apiClient } from "@/lib/apiClient";
+import type { UseDaresReturn } from "@/features/dares/hooks/useDares";
 import type { SentDare } from "@/features/dares/types";
 
 const incoming: SentDare = {
@@ -90,3 +91,80 @@ describe("useDares", () => {
         expect(result.current.error).toBe("offline");
     });
 });
+
+describe("useDares polling cost", () => {
+    /** Counts requests per endpoint and lets the active payload be swapped mid-test. */
+    function mockCounting(active: () => SentDare[]) {
+        const calls = { active: 0, history: 0, catalog: 0, stats: 0 };
+        jest.spyOn(apiClient, "get").mockImplementation(async (path: string) => {
+            if (path.startsWith("/v1/dares?filter=active")) { calls.active += 1; return { dares: active() } as never; }
+            if (path.startsWith("/v1/dares?filter=history")) { calls.history += 1; return { dares: [] } as never; }
+            if (path === "/v1/dares/packs") { calls.catalog += 1; return catalog as never; }
+            if (path === "/v1/dares/stats") { calls.stats += 1; return stats as never; }
+            throw new Error(`unexpected path ${path}`);
+        });
+        return calls;
+    }
+
+    const flush = async () => { await act(async () => { await Promise.resolve(); await Promise.resolve(); }); };
+    const tick = async () => {
+        await flush();
+        await act(async () => { jest.advanceTimersByTime(5_000); });
+        await flush();
+    };
+
+    beforeEach(() => { jest.restoreAllMocks(); jest.useFakeTimers(); });
+    afterEach(() => jest.useRealTimers());
+
+    it("polls the active list alone and re-reads the static endpoints only when it changes", async () => {
+        let current: SentDare[] = [incoming];
+        const calls = mockCounting(() => current);
+        const { result } = renderHook(() => useDares({ isFocused: true }));
+        await flush();
+        expect(result.current.loading).toBe(false);
+        // The first pass is a full load: nothing is cached yet.
+        expect(calls).toEqual({ active: 1, history: 1, catalog: 1, stats: 1 });
+
+        await tick();
+        await tick();
+        // Two quiet polls cost one request each, not four. The catalogue and the
+        // stats cannot move while the active set is byte-for-byte identical.
+        expect(calls).toEqual({ active: 3, history: 1, catalog: 1, stats: 1 });
+
+        current = [{ ...incoming, status: "active" }];
+        await tick();
+        expect(calls).toEqual({ active: 4, history: 2, catalog: 2, stats: 2 });
+        expect(result.current.active[0]?.status).toBe("active");
+
+        await tick();
+        expect(calls).toEqual({ active: 5, history: 2, catalog: 2, stats: 2 });
+    });
+
+    it("issues nothing at all while the screen is not on top", async () => {
+        const calls = mockCounting(() => [incoming]);
+        const { rerender } = renderHook<UseDaresReturn, { isFocused: boolean }>(
+            ({ isFocused }) => useDares({ isFocused }),
+            { initialProps: { isFocused: false } },
+        );
+        await tick();
+        await tick();
+        expect(calls).toEqual({ active: 0, history: 0, catalog: 0, stats: 0 });
+
+        rerender({ isFocused: true });
+        await flush();
+        expect(calls).toEqual({ active: 1, history: 1, catalog: 1, stats: 1 });
+    });
+
+    it("never overlaps two polls", async () => {
+        let release: (payload: { dares: SentDare[] }) => void = () => undefined;
+        jest.spyOn(apiClient, "get").mockImplementation(async (path: string) => {
+            if (path.startsWith("/v1/dares?filter=active")) return new Promise(resolve => { release = resolve; }) as never;
+            return { dares: [], ...catalog, ...stats } as never;
+        });
+        renderHook(() => useDares({ isFocused: true }));
+        await flush();
+        await act(async () => { jest.advanceTimersByTime(20_000); });
+        expect((apiClient.get as jest.Mock).mock.calls.filter(([path]) => String(path).includes("filter=active"))).toHaveLength(1);
+        await act(async () => { release({ dares: [] }); await Promise.resolve(); });
+    });
+});

apps/mobile/src/__tests__/hooks/useDrawingSync.test.ts

@@ -48,6 +48,60 @@ describe('useDrawingSync API polling', () => {
   });
 });
 
+describe('useDrawingSync focus gating', () => {
+  const handlers = {
+    onStrokeStart: jest.fn(), onStrokeContinue: jest.fn(), onStrokeEnd: jest.fn(),
+    onClearCanvas: jest.fn(), onUndo: jest.fn(), onRedo: jest.fn(),
+  };
+  beforeEach(() => { jest.clearAllMocks(); jest.useFakeTimers(); });
+  afterEach(() => jest.useRealTimers());
+
+  it('reads the canvas once on mount and then polls only while the screen is on top', async () => {
+    (appDataApi.getLiveDraw as jest.Mock).mockResolvedValue({ strokes: [], revision: 1, updated_at: 'one', updated_by: userId });
+    const onLoadStrokes = jest.fn();
+    const { rerender } = renderHook<unknown, { isFocused: boolean }>(({ isFocused }) => useDrawingSync({
+      coupleId: 'couple', userId, onLoadStrokes, isFocused, ...handlers,
+    }), { initialProps: { isFocused: false } });
+
+    await waitFor(() => expect(appDataApi.getLiveDraw).toHaveBeenCalledTimes(1));
+    // A canvas nobody is looking at costs nothing beyond the state it loaded with.
+    await act(async () => { jest.advanceTimersByTime(750 * 8); await Promise.resolve(); });
+    expect(appDataApi.getLiveDraw).toHaveBeenCalledTimes(1);
+
+    rerender({ isFocused: true });
+    await act(async () => { jest.advanceTimersByTime(750); await Promise.resolve(); });
+    expect(appDataApi.getLiveDraw).toHaveBeenCalledTimes(2);
+
+    rerender({ isFocused: false });
+    await act(async () => { jest.advanceTimersByTime(750 * 8); await Promise.resolve(); });
+    expect(appDataApi.getLiveDraw).toHaveBeenCalledTimes(2);
+  });
+
+  it('never polls over its own write in flight', async () => {
+    (appDataApi.getLiveDraw as jest.Mock).mockResolvedValue({ strokes: [], revision: 1, updated_at: 'one', updated_by: userId });
+    let release: (state: unknown) => void = () => undefined;
+    (appDataApi.putLiveDraw as jest.Mock).mockReturnValue(new Promise(resolve => { release = resolve; }));
+    const onLoadStrokes = jest.fn();
+    const { result } = renderHook(() => useDrawingSync({
+      coupleId: 'couple', userId, onLoadStrokes, isFocused: true, ...handlers,
+    }));
+    await waitFor(() => expect(appDataApi.getLiveDraw).toHaveBeenCalledTimes(1));
+
+    const pending = result.current.persistStrokes([stroke]);
+    await act(async () => { jest.advanceTimersByTime(750 * 4); await Promise.resolve(); });
+    // The write returns the authoritative state; reading over the top of it would
+    // only race a revision we are about to replace.
+    expect(appDataApi.getLiveDraw).toHaveBeenCalledTimes(1);
+
+    await act(async () => {
+      release({ strokes: [stroke], revision: 2, updated_at: 'two', updated_by: userId });
+      await pending;
+    });
+    await act(async () => { jest.advanceTimersByTime(750); await Promise.resolve(); });
+    expect(appDataApi.getLiveDraw).toHaveBeenCalledTimes(2);
+  });
+});
+
 describe('useDrawingSync stroke deduplication', () => {
   const at = (id: string, points: number, userId = 'u1') => ({
     id, userId, points: Array.from({ length: points }, (_, i) => ({ x: i, y: i })),

apps/mobile/src/__tests__/hooks/useMessageSubscription.test.ts

@@ -4,85 +4,183 @@ import { chatApi } from '@/lib/chatApi';
 
 jest.mock('@/lib/chatApi', () => ({ chatApi: { listMessages: jest.fn(), markRead: jest.fn() } }));
 
-const message = (id: string, user_id = 'partner') => ({ id, match_id: 'match1', user_id, content: id } as any);
+const message = (id: string, user_id = 'partner', overrides: Record<string, unknown> = {}) => ({
+    id, match_id: 'match1', user_id, content: id,
+    created_at: '2026-08-27T12:00:00Z', read_at: null, ...overrides,
+} as any);
 
-describe('useMessageSubscription API polling', () => {
+const snapshot = (messages: any[], server_time = 'cursor-1') => ({ messages, removed_ids: [], server_time, complete: true });
+const delta = (messages: any[], options: { removed?: string[]; server_time?: string; typing?: boolean } = {}) => ({
+    messages,
+    removed_ids: options.removed ?? [],
+    server_time: options.server_time ?? 'cursor-2',
+    complete: false,
+    ...(options.typing === undefined ? {} : { typing: { typing: options.typing, expires_at: null } }),
+});
+
+const listMessages = chatApi.listMessages as jest.Mock;
+const markRead = chatApi.markRead as jest.Mock;
+
+describe('useMessageSubscription incremental polling', () => {
     beforeEach(() => {
         jest.clearAllMocks();
         jest.useFakeTimers();
-        (chatApi.listMessages as jest.Mock).mockResolvedValue({ messages: [] });
-        (chatApi.markRead as jest.Mock).mockResolvedValue({ updated: 0, read_at: 'now' });
+        listMessages.mockResolvedValue(snapshot([]));
+        markRead.mockResolvedValue({ updated: 0, read_at: 'now' });
     });
     afterEach(() => jest.useRealTimers());
 
-    it('fails closed without both a match and authenticated user', async () => {
-        const { result, rerender } = renderHook<ReturnType<typeof useMessageSubscription>, { matchId: string | undefined; userId: string | undefined }>(
+    const mount = (config: Partial<Parameters<typeof useMessageSubscription>[0]> = {}) =>
+        renderHook(() => useMessageSubscription({ matchId: 'match1', userId: 'me', pollInterval: 500, ...config }));
+
+    it('fails closed without both match and authenticated user', () => {
+        const { rerender } = renderHook<ReturnType<typeof useMessageSubscription>, { matchId: string | undefined; userId: string | undefined }>(
             ({ matchId, userId }) => useMessageSubscription({ matchId, userId }),
             { initialProps: { matchId: undefined as string | undefined, userId: 'me' as string | undefined } },
         );
-        expect(result.current.loading).toBe(false);
-        expect(chatApi.listMessages).not.toHaveBeenCalled();
+        expect(listMessages).not.toHaveBeenCalled();
         rerender({ matchId: 'match1', userId: undefined });
-        expect(chatApi.listMessages).not.toHaveBeenCalled();
+        expect(listMessages).not.toHaveBeenCalled();
     });
 
-    it('loads initial messages without treating them as newly arrived', async () => {
+    it('loads a snapshot first, then requests only changes since the server cursor', async () => {
+        listMessages.mockResolvedValueOnce(snapshot([message('m1')], 'cursor-1'));
+        const { result } = mount();
+        await waitFor(() => expect(result.current.loading).toBe(false));
+        expect(listMessages).toHaveBeenNthCalledWith(1, 'match1', { typing: true });
+
+        await act(async () => { jest.advanceTimersByTime(500); });
+        await waitFor(() => expect(listMessages).toHaveBeenCalledTimes(2));
+        expect(listMessages).toHaveBeenNthCalledWith(2, 'match1', { since: 'cursor-1', typing: true });
+    });
+
+    it('keeps cached messages, and their identity, when a delta carries nothing', async () => {
+        listMessages.mockResolvedValueOnce(snapshot([message('m1', 'partner', { read_at: 'seen' })]));
+        listMessages.mockResolvedValue(delta([]));
+        const { result } = mount();
+        await waitFor(() => expect(result.current.messages).toHaveLength(1));
+        const cached = result.current.messages;
+
+        await act(async () => { jest.advanceTimersByTime(500); });
+        await waitFor(() => expect(listMessages).toHaveBeenCalledTimes(2));
+        expect(result.current.messages).toBe(cached);
+        expect(result.current.loading).toBe(false);
+    });
+
+    it('merges delta rows by id, applies self-deletions, and keeps newest first', async () => {
+        listMessages.mockResolvedValueOnce(snapshot([
+            message('m2', 'me', { created_at: '2026-08-27T12:00:02Z' }),
+            message('m1', 'partner', { created_at: '2026-08-27T12:00:01Z', read_at: 'seen' }),
+        ]));
+        listMessages.mockResolvedValueOnce(delta([
+            message('m3', 'partner', { created_at: '2026-08-27T12:00:03Z', read_at: 'seen' }),
+            message('m1', 'partner', { created_at: '2026-08-27T12:00:01Z', read_at: 'seen', deleted_at: 'gone' }),
+        ], { removed: ['m2'] }));
+        const { result } = mount();
+        await waitFor(() => expect(result.current.messages).toHaveLength(2));
+
+        await act(async () => { jest.advanceTimersByTime(500); });
+        await waitFor(() => expect(result.current.messages).toHaveLength(2));
+        expect(result.current.messages.map(m => m.id)).toEqual(['m3', 'm1']);
+        expect(result.current.messages[1]?.deleted_at).toBe('gone');
+    });
+
+    it('marks read only when the response holds an unread partner message', async () => {
+        listMessages.mockResolvedValueOnce(snapshot([message('m1', 'partner')]));
+        listMessages.mockResolvedValueOnce(delta([message('m2', 'me')]));
+        listMessages.mockResolvedValueOnce(delta([message('m1', 'partner', { read_at: 'seen' })]));
+        const { result } = mount();
+        await waitFor(() => expect(markRead).toHaveBeenCalledTimes(1));
+
+        await act(async () => { jest.advanceTimersByTime(500); });
+        await waitFor(() => expect(listMessages).toHaveBeenCalledTimes(2));
+        await act(async () => { jest.advanceTimersByTime(500); });
+        await waitFor(() => expect(listMessages).toHaveBeenCalledTimes(3));
+        expect(markRead).toHaveBeenCalledTimes(1);
+        expect(result.current.messages).toHaveLength(2);
+    });
+
+    it('issues no request at all while the chat is not focused', async () => {
+        const { rerender } = renderHook<ReturnType<typeof useMessageSubscription>, { focused: boolean }>(
+            ({ focused }) => useMessageSubscription({ matchId: 'match1', userId: 'me', pollInterval: 500, isFocused: focused }),
+            { initialProps: { focused: false } },
+        );
+        await act(async () => { jest.advanceTimersByTime(2_000); });
+        expect(listMessages).not.toHaveBeenCalled();
+        expect(markRead).not.toHaveBeenCalled();
+
+        rerender({ focused: true });
+        await waitFor(() => expect(listMessages).toHaveBeenCalledTimes(1));
+
+        rerender({ focused: false });
+        const callsAtBlur = listMessages.mock.calls.length;
+        await act(async () => { jest.advanceTimersByTime(2_000); });
+        expect(listMessages).toHaveBeenCalledTimes(callsAtBlur);
+    });
+
+    it('reports partner arrivals once, and never for the initial load or own messages', async () => {
         const onNewMessage = jest.fn();
-        (chatApi.listMessages as jest.Mock).mockResolvedValue({ messages: [message('m1')] });
-        const { result } = renderHook(() => useMessageSubscription({ matchId: 'match1', userId: 'me', onNewMessage }));
+        listMessages.mockResolvedValueOnce(snapshot([message('m1', 'partner', { read_at: 'seen' })]));
+        listMessages.mockResolvedValueOnce(delta([message('mine', 'me')]));
+        listMessages.mockResolvedValueOnce(delta([message('m2', 'partner')]));
+        listMessages.mockResolvedValueOnce(delta([message('m2', 'partner', { read_at: 'seen' })]));
+        const { result } = mount({ onNewMessage });
         await waitFor(() => expect(result.current.loading).toBe(false));
-        expect(result.current.messages).toEqual([message('m1')]);
         expect(onNewMessage).not.toHaveBeenCalled();
-        expect(chatApi.markRead).not.toHaveBeenCalled();
-    });
 
-    it('refreshes on the polling interval, marks focused messages read, and reports new partner messages', async () => {
-        const onNewMessage = jest.fn();
-        (chatApi.listMessages as jest.Mock)
-            .mockResolvedValueOnce({ messages: [message('m1')] })
-            .mockResolvedValueOnce({ messages: [message('m2'), message('m1')] });
-        const { result } = renderHook(() => useMessageSubscription({ matchId: 'match1', userId: 'me', onNewMessage, pollInterval: 500 }));
-        await waitFor(() => expect(result.current.loading).toBe(false));
-        act(() => { result.current.isFocusedRef.current = true; });
-        await act(async () => { jest.advanceTimersByTime(500); await Promise.resolve(); });
-        await waitFor(() => expect(result.current.messages[0]?.id).toBe('m2'));
-        expect(chatApi.markRead).toHaveBeenCalledWith('match1');
+        for (const expected of [2, 3, 4]) {
+            await act(async () => { jest.advanceTimersByTime(500); });
+            await waitFor(() => expect(listMessages).toHaveBeenCalledTimes(expected));
+        }
         expect(onNewMessage).toHaveBeenCalledTimes(1);
     });
 
-    it('does not notify for the current user own newly polled message', async () => {
-        const onNewMessage = jest.fn();
-        (chatApi.listMessages as jest.Mock)
-            .mockResolvedValueOnce({ messages: [] })
-            .mockResolvedValueOnce({ messages: [message('mine', 'me')] });
-        const { result } = renderHook(() => useMessageSubscription({ matchId: 'match1', userId: 'me', onNewMessage, pollInterval: 500 }));
-        await waitFor(() => expect(result.current.loading).toBe(false));
-        await act(async () => { jest.advanceTimersByTime(500); await Promise.resolve(); });
-        expect(onNewMessage).not.toHaveBeenCalled();
+    it('reads partner typing state out of the message response', async () => {
+        listMessages.mockResolvedValueOnce({ ...snapshot([]), typing: { typing: true, expires_at: 'later' } });
+        const { result } = mount();
+        await waitFor(() => expect(result.current.partnerTyping).toBe(true));
+
+        listMessages.mockResolvedValueOnce(delta([], { typing: false }));
+        await act(async () => { jest.advanceTimersByTime(500); });
+        await waitFor(() => expect(result.current.partnerTyping).toBe(false));
     });
 
     it('surfaces loading completion and preserves a usable empty state after an API error', async () => {
-        (chatApi.listMessages as jest.Mock).mockRejectedValueOnce(new Error('forbidden'));
-        const { result } = renderHook(() => useMessageSubscription({ matchId: 'match1', userId: 'me' }));
+        listMessages.mockRejectedValueOnce(new Error('forbidden'));
+        const { result } = mount();
         await waitFor(() => expect(result.current.loading).toBe(false));
         expect(result.current.messages).toEqual([]);
     });
 
-    it('prevents overlapping polls and clears the interval on unmount', async () => {
-        let resolveFirst!: (value: { messages: any[] }) => void;
-        (chatApi.listMessages as jest.Mock).mockImplementationOnce(() => new Promise(resolve => { resolveFirst = resolve; }));
-        const { unmount } = renderHook(() => useMessageSubscription({ matchId: 'match1', userId: 'me', pollInterval: 500 }));
-        expect(chatApi.listMessages).toHaveBeenCalledTimes(1);
-        act(() => { jest.advanceTimersByTime(1_500); });
-        expect(chatApi.listMessages).toHaveBeenCalledTimes(1);
-        await act(async () => resolveFirst({ messages: [] }));
+    it('prevents overlapping polls and stops on unmount', async () => {
+        let resolveFirst!: (value: unknown) => void;
+        listMessages.mockImplementationOnce(() => new Promise(resolve => { resolveFirst = resolve; }));
+        const { unmount } = mount();
+        expect(listMessages).toHaveBeenCalledTimes(1);
+        await act(async () => { jest.advanceTimersByTime(1_500); });
+        expect(listMessages).toHaveBeenCalledTimes(1);
+
+        await act(async () => { resolveFirst(snapshot([])); });
         unmount();
-        act(() => { jest.advanceTimersByTime(2_000); });
-        expect(chatApi.listMessages).toHaveBeenCalledTimes(1);
+        await act(async () => { jest.advanceTimersByTime(2_000); });
+        expect(listMessages).toHaveBeenCalledTimes(1);
+    });
+
+    it('restarts immediately, and without a stale cursor, for a different match', async () => {
+        listMessages.mockResolvedValue(snapshot([message('m1')], 'cursor-1'));
+        const { result, rerender } = renderHook<ReturnType<typeof useMessageSubscription>, { matchId: string }>(
+            ({ matchId }) => useMessageSubscription({ matchId, userId: 'me', pollInterval: 500 }),
+            { initialProps: { matchId: 'match1' } },
+        );
+        await waitFor(() => expect(result.current.messages).toHaveLength(1));
+
+        rerender({ matchId: 'match2' });
+        await waitFor(() => expect(listMessages).toHaveBeenCalledTimes(2));
+        expect(listMessages).toHaveBeenNthCalledWith(2, 'match2', { typing: true });
     });
 
     it('supports optimistic external updates', async () => {
-        const { result } = renderHook(() => useMessageSubscription({ matchId: 'match1', userId: 'me' }));
+        const { result } = mount();
         await waitFor(() => expect(result.current.loading).toBe(false));
         act(() => result.current.setMessages([message('optimistic', 'me')]));
         expect(result.current.messages[0]?.id).toBe('optimistic');

apps/mobile/src/__tests__/hooks/usePolling.test.ts

@@ -0,0 +1,141 @@
+import { act, renderHook } from '@testing-library/react-native';
+import { usePolling } from '@/hooks/usePolling';
+
+const mockForeground = { value: true };
+const mockListeners = new Set<(foreground: boolean) => void>();
+
+jest.mock('@/lib/appForeground', () => ({
+    isForeground: () => mockForeground.value,
+    subscribeToForeground: (listener: (foreground: boolean) => void) => {
+        mockListeners.add(listener);
+        return () => { mockListeners.delete(listener); };
+    },
+}));
+
+const setForeground = async (value: boolean) => {
+    await act(async () => {
+        mockForeground.value = value;
+        for (const listener of [...mockListeners]) listener(value);
+    });
+};
+// The next run is scheduled once the previous one settles, so let pending
+// promises land before and after moving the clock.
+const flush = async () => { await act(async () => { await Promise.resolve(); await Promise.resolve(); }); };
+const tick = async (ms: number) => {
+    await flush();
+    await act(async () => { jest.advanceTimersByTime(ms); });
+    await flush();
+};
+
+describe('usePolling', () => {
+    beforeEach(() => {
+        jest.clearAllMocks();
+        jest.useFakeTimers();
+        mockForeground.value = true;
+        mockListeners.clear();
+    });
+    afterEach(() => jest.useRealTimers());
+
+    it('runs once immediately and then on the interval', async () => {
+        const task = jest.fn(async () => undefined);
+        renderHook(() => usePolling(task, { intervalMs: 100 }));
+        expect(task).toHaveBeenCalledTimes(1);
+        await tick(100);
+        expect(task).toHaveBeenCalledTimes(2);
+        await tick(100);
+        expect(task).toHaveBeenCalledTimes(3);
+    });
+
+    it('skips the leading run when asked to', async () => {
+        const task = jest.fn(async () => undefined);
+        renderHook(() => usePolling(task, { intervalMs: 100, leading: false }));
+        expect(task).not.toHaveBeenCalled();
+        await tick(100);
+        expect(task).toHaveBeenCalledTimes(1);
+    });
+
+    it('issues nothing while disabled and starts once enabled', async () => {
+        const task = jest.fn(async () => undefined);
+        const { rerender } = renderHook<void, { enabled: boolean }>(({ enabled }) => usePolling(task, { intervalMs: 100, enabled }), {
+            initialProps: { enabled: false },
+        });
+        await tick(1_000);
+        expect(task).not.toHaveBeenCalled();
+        rerender({ enabled: true });
+        expect(task).toHaveBeenCalledTimes(1);
+    });
+
+    it('stops while the app is backgrounded and catches up on return', async () => {
+        const task = jest.fn(async () => undefined);
+        renderHook(() => usePolling(task, { intervalMs: 100 }));
+        expect(task).toHaveBeenCalledTimes(1);
+
+        await setForeground(false);
+        await tick(1_000);
+        expect(task).toHaveBeenCalledTimes(1);
+
+        await setForeground(true);
+        expect(task).toHaveBeenCalledTimes(2);
+        await tick(100);
+        expect(task).toHaveBeenCalledTimes(3);
+    });
+
+    it('never runs two tasks concurrently', async () => {
+        let release!: () => void;
+        const task = jest.fn(() => new Promise<void>(resolve => { release = resolve; }));
+        renderHook(() => usePolling(task, { intervalMs: 100 }));
+        expect(task).toHaveBeenCalledTimes(1);
+
+        await tick(500);
+        expect(task).toHaveBeenCalledTimes(1);
+
+        await act(async () => { release(); });
+        await tick(100);
+        expect(task).toHaveBeenCalledTimes(2);
+    });
+
+    it('backs off after consecutive failures and recovers after a success', async () => {
+        const task = jest.fn(async (): Promise<void> => { throw new Error('offline'); });
+        renderHook(() => usePolling(task, { intervalMs: 100, maxIntervalMs: 400 }));
+        expect(task).toHaveBeenCalledTimes(1);
+
+        await tick(100);
+        expect(task).toHaveBeenCalledTimes(1);
+        await tick(100);
+        expect(task).toHaveBeenCalledTimes(2);
+
+        await tick(399);
+        expect(task).toHaveBeenCalledTimes(2);
+        await tick(1);
+        expect(task).toHaveBeenCalledTimes(3);
+
+        task.mockImplementation(async () => undefined);
+        await tick(400);
+        expect(task).toHaveBeenCalledTimes(4);
+        await tick(100);
+        expect(task).toHaveBeenCalledTimes(5);
+    });
+
+    it('restarts immediately when the reset key changes', async () => {
+        const task = jest.fn(async () => undefined);
+        const { rerender } = renderHook<void, { resetKey: string }>(({ resetKey }) => usePolling(task, { intervalMs: 100, resetKey }), {
+            initialProps: { resetKey: 'a' },
+        });
+        expect(task).toHaveBeenCalledTimes(1);
+        rerender({ resetKey: 'b' });
+        expect(task).toHaveBeenCalledTimes(2);
+        await tick(50);
+        expect(task).toHaveBeenCalledTimes(2);
+    });
+
+    it('stops and unsubscribes on unmount', async () => {
+        const task = jest.fn(async () => undefined);
+        const { unmount } = renderHook(() => usePolling(task, { intervalMs: 100 }));
+        await tick(100);
+        expect(task).toHaveBeenCalledTimes(2);
+        unmount();
+        expect(mockListeners.size).toBe(0);
+        await tick(1_000);
+        expect(task).toHaveBeenCalledTimes(2);
+    });
+});

apps/mobile/src/__tests__/hooks/useTypingIndicator.test.ts

@@ -76,4 +76,22 @@ describe('useTypingIndicator API polling', () => {
         act(() => { jest.advanceTimersByTime(2_000); });
         expect(chatApi.getTyping).toHaveBeenCalledTimes(calls);
     });
+    it('stops polling and mirrors typing state supplied by the message poll', async () => {
+        const { result, rerender } = renderHook<ReturnType<typeof useTypingIndicator>, { externalTyping: boolean | undefined }>(
+            ({ externalTyping }) => useTypingIndicator({ channelName: 'chat:match1', userId: 'me', pollInterval: 500, externalTyping }),
+            { initialProps: { externalTyping: undefined as boolean | undefined } },
+        );
+        await act(async () => { await Promise.resolve(); });
+        const callsBeforeFolding = (chatApi.getTyping as jest.Mock).mock.calls.length;
+
+        rerender({ externalTyping: true });
+        expect(result.current.partnerTyping).toBe(true);
+        await act(async () => { jest.advanceTimersByTime(5_000); });
+        expect(chatApi.getTyping).toHaveBeenCalledTimes(callsBeforeFolding);
+
+        act(() => result.current.clearTypingIndicator());
+        expect(result.current.partnerTyping).toBe(false);
+        rerender({ externalTyping: false });
+        expect(result.current.partnerTyping).toBe(false);
+    });
 });

apps/mobile/src/__tests__/lib/appForeground.test.ts

@@ -0,0 +1,36 @@
+import { AppState } from 'react-native';
+import { isForeground, isForegroundState, subscribeToForeground } from '@/lib/appForeground';
+
+describe('appForeground', () => {
+    afterEach(() => jest.restoreAllMocks());
+
+    it('treats only background and inactive as away', () => {
+        expect(isForegroundState('active')).toBe(true);
+        expect(isForegroundState('background')).toBe(false);
+        expect(isForegroundState('inactive')).toBe(false);
+        // Unknown states — including whatever a test harness leaves behind — must
+        // fail towards running, never towards disabling recurring work forever.
+        expect(isForegroundState(undefined)).toBe(true);
+        expect(isForegroundState('extension')).toBe(true);
+    });
+
+    it('reads the current state and reports transitions until unsubscribed', () => {
+        let emit: (state: string) => void = () => undefined;
+        const remove = jest.fn();
+        jest.spyOn(AppState, 'addEventListener').mockImplementation(((_: string, handler: (state: string) => void) => {
+            emit = handler;
+            return { remove } as never;
+        }) as never);
+
+        expect(isForeground()).toBe(isForegroundState(AppState.currentState));
+
+        const seen: boolean[] = [];
+        const unsubscribe = subscribeToForeground(value => seen.push(value));
+        emit('background');
+        emit('active');
+        expect(seen).toEqual([false, true]);
+
+        unsubscribe();
+        expect(remove).toHaveBeenCalled();
+    });
+});

apps/mobile/src/__tests__/lib/chatApi.test.ts

@@ -24,6 +24,18 @@ describe('chatApi', () => {
         expect(apiClient.get).toHaveBeenNthCalledWith(2, '/v1/matches/match%2Fid/typing');
     });
 
+    it('encodes the delta cursor and folded typing request into the message query', async () => {
+        (apiClient.get as jest.Mock).mockResolvedValue({ messages: [], removed_ids: [], server_time: 'now', complete: false });
+
+        await chatApi.listMessages('match1', { typing: true });
+        await chatApi.listMessages('match1', { since: '2026-08-27T12:00:00.000+01:00' });
+        await chatApi.listMessages('match1', { since: '2026-08-27T12:00:00.000Z', typing: true });
+
+        expect(apiClient.get).toHaveBeenNthCalledWith(1, '/v1/matches/match1/messages?typing=true');
+        expect(apiClient.get).toHaveBeenNthCalledWith(2, '/v1/matches/match1/messages?since=2026-08-27T12%3A00%3A00.000%2B01%3A00');
+        expect(apiClient.get).toHaveBeenNthCalledWith(3, '/v1/matches/match1/messages?since=2026-08-27T12%3A00%3A00.000Z&typing=true');
+    });
+
     it('uses authenticated unread, receipt, deletion and reporting routes', async () => {
         (apiClient.get as jest.Mock).mockResolvedValue({ total: 0, by_match: {} });
         (apiClient.post as jest.Mock).mockResolvedValue({});

apps/mobile/src/__tests__/stores/matchStore.test.ts

@@ -45,9 +45,18 @@ describe('matchStore API behavior', () => {
         });
 
         it('guards concurrent loads and exhausted pagination', async () => {
-            useMatchStore.setState({ isLoading: true });
-            await useMatchStore.getState().fetchMatches(true);
-            useMatchStore.setState({ isLoading: false, hasMore: false });
+            // Overlap protection cannot key off the loading flags any more: a silent
+            // refresh raises none of them and still must not issue a second request.
+            let release: (page: { matches: unknown[]; totalCount: number }) => void = () => undefined;
+            (apiClient.get as jest.Mock).mockReturnValueOnce(new Promise(resolve => { release = resolve; }));
+            const inFlight = useMatchStore.getState().fetchMatches(true);
+            await useMatchStore.getState().fetchMatches(true, { silent: true });
+            expect(apiClient.get).toHaveBeenCalledTimes(1);
+            release({ matches: [], totalCount: 0 });
+            await inFlight;
+
+            (apiClient.get as jest.Mock).mockClear();
+            useMatchStore.setState({ hasMore: false });
             await useMatchStore.getState().fetchMatches(false);
             expect(apiClient.get).not.toHaveBeenCalled();
         });
@@ -147,7 +156,10 @@ describe('matchStore API behavior', () => {
         it('toggles archived visibility and triggers an initial fetch only', async () => {
             (apiClient.get as jest.Mock).mockResolvedValue({ matches: [], totalCount: 0 });
             useMatchStore.getState().toggleShowArchived();
-            await Promise.resolve();
+            // Let the floating fetch settle: its in-flight guard is module-scoped and
+            // is only released in a finally, so a half-run request would leak into
+            // the next test and silently suppress its archived fetch.
+            await jest.runOnlyPendingTimersAsync();
             expect(useMatchStore.getState().showArchived).toBe(true);
             expect(apiClient.get).toHaveBeenCalledTimes(1);
             useMatchStore.getState().toggleShowArchived();
@@ -178,11 +190,19 @@ describe('matchStore API behavior', () => {
         });
 
         it('updates current view and delegates an empty view fetch', () => {
+            const real = useMatchStore.getState().fetchArchivedMatches;
             const fetchArchivedMatches = jest.fn(async () => undefined);
             useMatchStore.setState({ fetchArchivedMatches });
+            try {
                 useMatchStore.getState().setCurrentView('archived');
                 expect(useMatchStore.getState()).toMatchObject({ currentView: 'archived', showArchived: true });
                 expect(fetchArchivedMatches).toHaveBeenCalled();
+            } finally {
+                // Actions live in the same store as the data, and clearMatches does not
+                // reset them: leaving the stub in place would silence every later test's
+                // archived fetch.
+                useMatchStore.setState({ fetchArchivedMatches: real });
+            }
         });
     });
 
@@ -225,6 +245,222 @@ describe('matchStore API behavior', () => {
         });
     });
 
+    describe('view switching and cache freshness', () => {
+        /** Answers each of the four view endpoints with an empty payload. */
+        const emptyViews = () => (apiClient.get as jest.Mock).mockImplementation(async (path: string) => {
+            if (path.startsWith('/v1/matches?archived=true')) return { matches: [], totalCount: 0 };
+            if (path.startsWith('/v1/matches')) return { matches: [], totalCount: 0, hasMore: false };
+            return { questions: [] };
+        });
+
+        it('switches between loaded views without a single extra request, even when every view is empty', async () => {
+            emptyViews();
+            const views = ['pending', 'their_turn', 'active', 'archived'] as const;
+
+            // First visit to each view loads it once.
+            for (const view of views) {
+                useMatchStore.getState().setCurrentView(view);
+                await jest.runOnlyPendingTimersAsync();
+            }
+            expect(apiClient.get).toHaveBeenCalledTimes(views.length);
+            expect(useMatchStore.getState()).toMatchObject({
+                matches: [], pendingQuestions: [], theirTurnQuestions: [], archivedMatches: [],
+            });
+
+            // Every subsequent switch is served from cache. An empty view is loaded,
+            // not unloaded: this is the bug where `array.length === 0` meant "never
+            // fetched" and made every visit pay for the same empty answer.
+            (apiClient.get as jest.Mock).mockClear();
+            for (const view of [...views, ...views].reverse()) {
+                useMatchStore.getState().setCurrentView(view);
+                await jest.runOnlyPendingTimersAsync();
+            }
+            expect(apiClient.get).not.toHaveBeenCalled();
+        });
+
+        it('keeps cached rows and raises no foreground spinner during a silent refresh', async () => {
+            (apiClient.get as jest.Mock).mockResolvedValueOnce({ matches: [match('cached', false)], totalCount: 1, hasMore: false });
+            await useMatchStore.getState().fetchMatches(true);
+            expect(useMatchStore.getState().matches.map(item => item.id)).toEqual(['cached']);
+
+            let release: (page: unknown) => void = () => undefined;
+            (apiClient.get as jest.Mock).mockReturnValueOnce(new Promise(resolve => { release = resolve; }));
+            const refreshing = useMatchStore.getState().fetchMatches(true, { silent: true });
+
+            // Mid-flight: the user still sees the rows they had, and neither the
+            // full-screen loader nor the pull-to-refresh spinner is showing.
+            expect(useMatchStore.getState()).toMatchObject({ isLoading: false, isRefreshing: false });
+            expect(useMatchStore.getState().matches.map(item => item.id)).toEqual(['cached']);
+
+            release({ matches: [match('fresh', false)], totalCount: 1, hasMore: false });
+            await refreshing;
+            expect(useMatchStore.getState().matches.map(item => item.id)).toEqual(['fresh']);
+        });
+
+        it('shows the pull-to-refresh spinner for a user-initiated refresh but never the initial loader', async () => {
+            (apiClient.get as jest.Mock).mockResolvedValueOnce({ matches: [match('cached', false)], totalCount: 1, hasMore: false });
+            await useMatchStore.getState().fetchMatches(true);
+
+            let release: (page: unknown) => void = () => undefined;
+            (apiClient.get as jest.Mock).mockReturnValueOnce(new Promise(resolve => { release = resolve; }));
+            const refreshing = useMatchStore.getState().fetchMatches(true);
+            expect(useMatchStore.getState()).toMatchObject({ isLoading: false, isRefreshing: true });
+            expect(useMatchStore.getState().matches.map(item => item.id)).toEqual(['cached']);
+            release({ matches: [], totalCount: 0, hasMore: false });
+            await refreshing;
+            expect(useMatchStore.getState()).toMatchObject({ isRefreshing: false });
+        });
+
+        it('keeps a silent list refresh out of the pending and their-turn loaders', async () => {
+            (apiClient.get as jest.Mock).mockResolvedValue({ questions: [pending('p1')] });
+            await useMatchStore.getState().fetchPendingQuestions();
+            await useMatchStore.getState().fetchTheirTurnQuestions();
+
+            let release: (page: unknown) => void = () => undefined;
+            (apiClient.get as jest.Mock).mockReturnValue(new Promise(resolve => { release = resolve; }));
+            const quiet = Promise.all([
+                useMatchStore.getState().fetchPendingQuestions({ silent: true }),
+                useMatchStore.getState().fetchTheirTurnQuestions({ silent: true }),
+            ]);
+            expect(useMatchStore.getState()).toMatchObject({ isLoadingPending: false, isLoadingTheirTurn: false });
+            expect(useMatchStore.getState().pendingQuestions).toHaveLength(1);
+            release({ questions: [] });
+            await quiet;
+        });
+    });
+
+    describe('account isolation (generation tokens)', () => {
+        it('does not let a stale fetchMatches response populate the store after sign-out, and lets the next account start immediately', async () => {
+            let release: (page: unknown) => void = () => undefined;
+            (apiClient.get as jest.Mock).mockReturnValueOnce(new Promise(resolve => { release = resolve; }));
+            const staleFetch = useMatchStore.getState().fetchMatches(true);
+
+            // Simulates sign-out/account switch while the request is still in flight.
+            useMatchStore.getState().clearMatches();
+            release({ matches: [match('stale')], totalCount: 1, hasMore: false });
+            await staleFetch;
+
+            expect(useMatchStore.getState().matches).toEqual([]);
+
+            (apiClient.get as jest.Mock).mockResolvedValueOnce({ matches: [match('fresh')], totalCount: 1, hasMore: false });
+            await useMatchStore.getState().fetchMatches(true);
+            expect(useMatchStore.getState().matches.map(item => item.id)).toEqual(['fresh']);
+        });
+
+        it('does not let a stale seen-marker write over the next account\'s list', async () => {
+            useMatchStore.setState({ matches: [match('theirs')], newMatchesCount: 1 });
+            let release: () => void = () => undefined;
+            (apiClient.patch as jest.Mock).mockReturnValueOnce(new Promise<void>(resolve => { release = () => resolve(); }));
+            const stale = useMatchStore.getState().markAsSeen('theirs');
+
+            useMatchStore.getState().clearMatches();
+            useMatchStore.setState({ matches: [match('mine')], newMatchesCount: 1 });
+            const untouched = useMatchStore.getState().matches;
+            release();
+            await stale;
+
+            // Not merely "the same ids": the previous account's response must not
+            // rewrite the array at all, because the recount it derives is only true
+            // of the rows that account had loaded.
+            expect(useMatchStore.getState().matches).toBe(untouched);
+            expect(useMatchStore.getState().newMatchesCount).toBe(1);
+        });
+
+        it('does not let a stale mark-all-seen clear the next account\'s new badges', async () => {
+            useMatchStore.setState({ matches: [match('theirs')], newMatchesCount: 1 });
+            let release: () => void = () => undefined;
+            (apiClient.patch as jest.Mock).mockReturnValueOnce(new Promise<void>(resolve => { release = () => resolve(); }));
+            const stale = useMatchStore.getState().markAllAsSeen();
+
+            useMatchStore.getState().clearMatches();
+            useMatchStore.setState({ matches: [match('mine', true), match('mine2', true)], newMatchesCount: 2 });
+            release();
+            await stale;
+
+            expect(useMatchStore.getState().matches.every(item => item.is_new)).toBe(true);
+            expect(useMatchStore.getState().newMatchesCount).toBe(2);
+        });
+
+        it('does not roll a failed archive or unarchive back into the next account', async () => {
+            jest.spyOn(console, 'error').mockImplementation(() => undefined);
+            let fail: (error: Error) => void = () => undefined;
+            (apiClient.put as jest.Mock).mockReturnValueOnce(new Promise((_resolve, reject) => { fail = reject; }));
+            useMatchStore.setState({ matches: [match('theirs')], archivedMatches: [], archivedMatchIds: new Set<string>(), totalCount: 1 });
+            const staleArchive = useMatchStore.getState().archiveMatch('theirs');
+
+            useMatchStore.getState().clearMatches();
+            useMatchStore.setState({ matches: [match('mine')], totalCount: 1 });
+            fail(new Error('forbidden'));
+            await staleArchive;
+
+            // The revert would otherwise put one couple's match into another's list.
+            expect(useMatchStore.getState().matches.map(item => item.id)).toEqual(['mine']);
+            expect(useMatchStore.getState().totalCount).toBe(1);
+
+            (apiClient.put as jest.Mock).mockReturnValueOnce(new Promise((_resolve, reject) => { fail = reject; }));
+            useMatchStore.setState({ archivedMatches: [match('theirsArchived')], archivedMatchIds: new Set(['theirsArchived']) });
+            const staleUnarchive = useMatchStore.getState().unarchiveMatch('theirsArchived');
+
+            useMatchStore.getState().clearMatches();
+            useMatchStore.setState({ archivedMatches: [match('mineArchived')], archivedMatchIds: new Set(['mineArchived']), totalCount: 0 });
+            fail(new Error('forbidden'));
+            await staleUnarchive;
+
+            expect(useMatchStore.getState().archivedMatches.map(item => item.id)).toEqual(['mineArchived']);
+            expect(useMatchStore.getState().totalCount).toBe(0);
+        });
+
+        it('does not carry a nudge cooldown across an account switch', async () => {
+            let release: (data: unknown) => void = () => undefined;
+            (appDataApi.sendNudge as jest.Mock).mockReturnValueOnce(new Promise(resolve => { release = resolve; }));
+            const staleSend = useMatchStore.getState().sendNudge();
+
+            useMatchStore.getState().clearMatches();
+            release({ success: true, notification_sent: true, next_nudge_available_at: '2026-08-28T00:00:00Z' });
+            await expect(staleSend).resolves.toEqual({ success: false, notificationSent: false });
+            expect(useMatchStore.getState().nudgeCooldownUntil).toBeNull();
+
+            // The 429 branch writes a cooldown too, and must be gated the same way.
+            let fail: (error: Error) => void = () => undefined;
+            (appDataApi.sendNudge as jest.Mock).mockReturnValueOnce(new Promise((_resolve, reject) => { fail = reject; }));
+            const staleLimit = useMatchStore.getState().sendNudge();
+            useMatchStore.getState().clearMatches();
+            fail(new ApiError('rate limited', 429, { cooldown_remaining_seconds: 60 }));
+            await staleLimit;
+            expect(useMatchStore.getState().nudgeCooldownUntil).toBeNull();
+        });
+
+        it('does not let a stale cooldown read clear the next account\'s cooldown', async () => {
+            let release: (profile: unknown) => void = () => undefined;
+            (appDataApi.nudgeStatus as jest.Mock).mockReturnValueOnce(new Promise(resolve => { release = resolve; }));
+            const stale = useMatchStore.getState().checkNudgeCooldown();
+
+            useMatchStore.getState().clearMatches();
+            const mine = new Date('2026-08-27T18:00:00Z');
+            useMatchStore.setState({ nudgeCooldownUntil: mine });
+            // The previous account not being in cooldown says nothing about this one.
+            release({ last_nudge_sent_at: null });
+            await stale;
+            expect(useMatchStore.getState().nudgeCooldownUntil).toEqual(mine);
+        });
+
+        it('does not let a stale fetchPendingQuestions response populate the store after sign-out, and lets the next account start immediately', async () => {
+            let release: (page: unknown) => void = () => undefined;
+            (apiClient.get as jest.Mock).mockReturnValueOnce(new Promise(resolve => { release = resolve; }));
+            const staleFetch = useMatchStore.getState().fetchPendingQuestions();
+
+            useMatchStore.getState().clearMatches();
+            release({ questions: [pending('stale')] });
+            await staleFetch;
+
+            expect(useMatchStore.getState().pendingQuestions).toEqual([]);
+
+            (apiClient.get as jest.Mock).mockResolvedValueOnce({ questions: [pending('fresh')] });
+            await useMatchStore.getState().fetchPendingQuestions();
+            expect(useMatchStore.getState().pendingQuestions.map(item => item.id)).toEqual(['fresh']);
+        });
+    });
+
     it('clearMatches resets all user-scoped state', () => {
         useMatchStore.setState({ matches: [match('m1')], archivedMatches: [match('m2')], pendingQuestions: [pending('p')], theirTurnQuestions: [pending('t')], currentView: 'archived', showArchived: true, isNudging: true });
         useMatchStore.getState().clearMatches();

apps/mobile/src/__tests__/stores/messageStore.test.ts

@@ -47,15 +47,25 @@ describe('messageStore API state', () => {
         expect(useMessageStore.getState()).toMatchObject({ unreadCount: 1, lastMessage: { id: 'new' } });
     });
 
-    it('marks partner messages read then reconciles global and per-match counts', async () => {
+    it('marks partner messages read and subtracts the cleared count without re-reading the total', async () => {
+        useMessageStore.setState({ unreadCount: 3 });
         (chatApi.markRead as jest.Mock).mockResolvedValue({ updated: 2, read_at: '2026-08-27T00:00:00.000Z' });
-        (chatApi.unread as jest.Mock).mockResolvedValue({ total: 1, by_match: { m2: 1 } });
         await useMessageStore.getState().markMatchMessagesAsRead('m1');
         expect(chatApi.markRead).toHaveBeenCalledWith('m1');
+        expect(chatApi.unread).not.toHaveBeenCalled();
         expect(useMessageStore.getState().unreadCount).toBe(1);
         expect(useMatchStore.getState().matches[0]?.unreadCount).toBe(1);
     });
 
+    it('spends no request and touches no count when the read API cleared nothing', async () => {
+        useMessageStore.setState({ unreadCount: 3 });
+        (chatApi.markRead as jest.Mock).mockResolvedValue({ updated: 0, read_at: null });
+        await useMessageStore.getState().markMatchMessagesAsRead('m1');
+        expect(chatApi.unread).not.toHaveBeenCalled();
+        expect(useMessageStore.getState().unreadCount).toBe(3);
+        expect(useMatchStore.getState().matches[0]?.unreadCount).toBe(3);
+    });
+
     it('does not mark read without an authenticated user', async () => {
         useAuthStore.setState({ user: null } as any);
         await useMessageStore.getState().markMatchMessagesAsRead('m1');
@@ -69,6 +79,42 @@ describe('messageStore API state', () => {
         expect(useMatchStore.getState().matches[0]?.unreadCount).toBe(3);
     });
 
+    describe('account isolation (generation tokens)', () => {
+        it('does not let a stale unread total become the next account\'s badge', async () => {
+            let release: (value: unknown) => void = () => undefined;
+            (chatApi.unread as jest.Mock).mockReturnValueOnce(new Promise(resolve => { release = resolve; }));
+            const staleFetch = useMessageStore.getState().fetchUnreadCount();
+
+            // Sign-out or leaving a couple, while the request is still open.
+            useMessageStore.getState().clearMessages();
+            useMessageStore.setState({ unreadCount: 2 });
+
+            release({ total: 9, by_match: { m1: 9 } });
+            await staleFetch;
+
+            expect(useMessageStore.getState().unreadCount).toBe(2);
+        });
+
+        it('does not subtract a stale read receipt from the next account\'s badge', async () => {
+            useMessageStore.setState({ unreadCount: 3 });
+            let release: (value: unknown) => void = () => undefined;
+            (chatApi.markRead as jest.Mock).mockReturnValueOnce(new Promise(resolve => { release = resolve; }));
+            const staleRead = useMessageStore.getState().markMatchMessagesAsRead('m1');
+
+            useMessageStore.getState().clearMessages();
+            useMessageStore.setState({ unreadCount: 2 });
+            useMatchStore.setState({ matches: [{ id: 'm1', unreadCount: 2 } as any] });
+
+            release({ updated: 3, read_at: '2026-08-27T00:00:00.000Z' });
+            await staleRead;
+
+            // The badge is wrong whatever the match id; reusing 'm1' also makes the
+            // second half of the damage — the per-match count — visible.
+            expect(useMessageStore.getState().unreadCount).toBe(2);
+            expect(useMatchStore.getState().matches[0]?.unreadCount).toBe(2);
+        });
+    });
+
     it('clears transient message state', () => {
         useMessageStore.setState({ unreadCount: 3, lastMessage: { id: 'last' } as any, activeMatchId: 'm1' });
         useMessageStore.getState().clearLastMessage();

apps/mobile/src/__tests__/stores/packsStore.test.ts

@@ -64,4 +64,69 @@ describe('packsStore standalone API integration', () => {
         expect(getSpy).not.toHaveBeenCalled();
         expect(usePacksStore.getState().enabledPackIds).toEqual([]);
     });
+
+    describe('account isolation (generation tokens)', () => {
+        it('does not let a stale fetchEnabledPacks response populate the store after clearPacks, and lets the next account start immediately', async () => {
+            let release: (page: unknown) => void = () => undefined;
+            const getSpy = jest.spyOn(apiClient, 'get').mockReturnValueOnce(new Promise(resolve => { release = resolve; }));
+            const staleFetch = usePacksStore.getState().fetchEnabledPacks();
+
+            // Simulates sign-out/account switch while the request is still in flight.
+            usePacksStore.getState().clearPacks();
+            release({ enabledPackIds: ['stale-pack'] });
+            await staleFetch;
+
+            expect(usePacksStore.getState().enabledPackIds).toEqual([]);
+
+            getSpy.mockResolvedValueOnce({ enabledPackIds: ['fresh-pack'] });
+            await usePacksStore.getState().fetchEnabledPacks();
+            expect(usePacksStore.getState().enabledPackIds).toEqual(['fresh-pack']);
+        });
+
+        it('does not let a stale fetchPackProgress response populate the store after clearPacks, and lets the next account start immediately', async () => {
+            let release: (page: unknown) => void = () => undefined;
+            const getSpy = jest.spyOn(apiClient, 'get').mockReturnValueOnce(new Promise(resolve => { release = resolve; }));
+            const staleFetch = usePacksStore.getState().fetchPackProgress();
+
+            usePacksStore.getState().clearPacks();
+            release({ progress: [{ packId: 'stale', totalQuestions: 1, answeredQuestions: 1 }] });
+            await staleFetch;
+
+            expect(usePacksStore.getState().packProgress.size).toBe(0);
+
+            getSpy.mockResolvedValueOnce({ progress: [{ packId: 'fresh', totalQuestions: 2, answeredQuestions: 1 }] });
+            await usePacksStore.getState().fetchPackProgress();
+            expect(usePacksStore.getState().packProgress.get('fresh')).toEqual({ totalQuestions: 2, answeredQuestions: 1 });
+        });
+
+        it('does not let a stale toggle write the previous couple\'s pack selection', async () => {
+            usePacksStore.setState({ enabledPackIds: [] } as any);
+            let release: (value: unknown) => void = () => undefined;
+            jest.spyOn(apiClient, 'put').mockReturnValueOnce(new Promise(resolve => { release = resolve; }));
+            const staleToggle = usePacksStore.getState().togglePack('pack1');
+
+            usePacksStore.getState().clearPacks();
+            usePacksStore.setState({ enabledPackIds: ['next-couple-pack'] } as any);
+
+            release({ enabledPackIds: ['pack1'] });
+            await expect(staleToggle).resolves.toEqual({ success: false, reason: 'stale' });
+            expect(usePacksStore.getState().enabledPackIds).toEqual(['next-couple-pack']);
+        });
+
+        it('does not roll a failed toggle back into the next couple\'s selection', async () => {
+            usePacksStore.setState({ enabledPackIds: ['pack1'] } as any);
+            let reject: (reason: unknown) => void = () => undefined;
+            jest.spyOn(apiClient, 'put').mockReturnValueOnce(new Promise((_resolve, fail) => { reject = fail; }));
+            jest.spyOn(console, 'error').mockImplementation(() => undefined);
+            const staleToggle = usePacksStore.getState().togglePack('pack1');
+
+            usePacksStore.getState().clearPacks();
+            usePacksStore.setState({ enabledPackIds: ['next-couple-pack'] } as any);
+
+            reject(new Error('offline'));
+            await expect(staleToggle).resolves.toEqual({ success: false, reason: 'stale' });
+            // The rollback would have re-added pack1, which this couple never enabled.
+            expect(usePacksStore.getState().enabledPackIds).toEqual(['next-couple-pack']);
+        });
+    });
 });

apps/mobile/src/__tests__/stores/responsesStore.test.ts

@@ -265,6 +265,53 @@ describe('responsesStore', () => {
         });
     });
 
+    describe('account isolation (generation tokens)', () => {
+        it('does not let a stale fetchResponses response populate the store after clearResponses, and lets the next account start immediately', async () => {
+            let resolve!: (value: unknown) => void;
+            apiGet.mockReturnValueOnce(new Promise((done) => { resolve = done; }));
+            const staleFetch = useResponsesStore.getState().fetchResponses(true);
+
+            // Simulates sign-out/account switch while the request is still in flight.
+            useResponsesStore.getState().clearResponses();
+            resolve({ responses: [response({ id: 'stale' })], totalCount: 1 });
+            await staleFetch;
+
+            expect(useResponsesStore.getState().responses).toEqual([]);
+
+            apiGet.mockResolvedValueOnce({ responses: [response({ id: 'fresh' })], totalCount: 1 });
+            await useResponsesStore.getState().fetchResponses(true);
+            expect(useResponsesStore.getState().responses.map((r) => r.id)).toEqual(['fresh']);
+        });
+
+        it('does not let a stale edit rewrite the next account\'s row or refresh its matches', async () => {
+            // Question ids come from the shared catalogue, so the same id names a real
+            // row in both accounts' lists: a stale edit would land on one of them.
+            const fetchMatches = jest.fn();
+            useMatchStore.setState({ fetchMatches } as any);
+            useResponsesStore.setState({
+                responses: [response({ id: 'alice', answer: 'maybe', has_match: false, match_id: undefined })],
+            });
+
+            let resolve!: (value: unknown) => void;
+            apiPatch.mockReturnValueOnce(new Promise((done) => { resolve = done; }));
+            const staleEdit = useResponsesStore.getState().updateResponse('q1', 'yes');
+
+            useResponsesStore.getState().clearResponses();
+            const next = [response({ id: 'bob', answer: 'no', has_match: false, match_id: undefined })];
+            useResponsesStore.setState({ responses: next });
+
+            resolve({ success: true, new_match: { id: 'm2' } });
+            // The caller still hears what the server did for the account that asked.
+            await expect(staleEdit).resolves.toMatchObject({ success: true });
+
+            expect(useResponsesStore.getState().responses).toBe(next);
+            expect(useResponsesStore.getState().responses[0]).toMatchObject({
+                id: 'bob', answer: 'no', has_match: false,
+            });
+            expect(fetchMatches).not.toHaveBeenCalled();
+        });
+    });
+
     describe('state controls', () => {
         it('sets and toggles grouping options', () => {
             useResponsesStore.getState().setGroupBy('pack');

apps/mobile/src/__tests__/stores/streakStore.test.ts

@@ -0,0 +1,58 @@
+import { apiClient } from '@/lib/apiClient';
+import { useAuthStore } from '@/store/authStore';
+import { type CoupleStreak, useStreakStore } from '@/store/streakStore';
+
+jest.mock('@/lib/apiClient', () => ({ apiClient: { get: jest.fn() } }));
+
+const apiGet = apiClient.get as jest.Mock;
+
+function streak(overrides: Partial<CoupleStreak> = {}): CoupleStreak {
+    return {
+        couple_id: 'couple1', current_streak: 1, longest_streak: 1,
+        last_active_date: '2026-08-27', last_completed_date: '2026-08-27',
+        you_answered_today: true, partner_answered_today: false,
+        partner_name: 'Partner', timezone: 'UTC', streak_celebrated_at: 0,
+        created_at: '2026-08-01T00:00:00.000Z', updated_at: '2026-08-27T00:00:00.000Z',
+        ...overrides,
+    };
+}
+
+describe('streakStore account isolation (generation tokens)', () => {
+    beforeEach(() => {
+        jest.clearAllMocks();
+        useStreakStore.setState({ streak: null, isLoading: false, error: null, loadedAt: null, generation: 0 });
+        useAuthStore.setState({ user: { id: 'me', couple_id: 'couple1' } } as any);
+    });
+
+    it('does not let a stale fetchStreak response populate the store after clearStreak, and lets the next account start immediately', async () => {
+        let resolve!: (value: unknown) => void;
+        apiGet.mockReturnValueOnce(new Promise((done) => { resolve = done; }));
+        const staleFetch = useStreakStore.getState().fetchStreak();
+
+        // Simulates sign-out/account switch while the request is still in flight.
+        useStreakStore.getState().clearStreak();
+        resolve({ streak: streak({ couple_id: 'stale-couple' }) });
+        await staleFetch;
+
+        expect(useStreakStore.getState().streak).toBeNull();
+        expect(useStreakStore.getState().loadedAt).toBeNull();
+
+        apiGet.mockResolvedValueOnce({ streak: streak({ couple_id: 'fresh-couple' }) });
+        await useStreakStore.getState().fetchStreak();
+        expect(useStreakStore.getState().streak?.couple_id).toBe('fresh-couple');
+        expect(useStreakStore.getState().loadedAt).not.toBeNull();
+    });
+
+    it('refreshStreak silently reloads only an already-loaded streak', async () => {
+        await useStreakStore.getState().refreshStreak();
+        expect(apiGet).not.toHaveBeenCalled();
+
+        apiGet.mockResolvedValueOnce({ streak: streak() });
+        await useStreakStore.getState().fetchStreak();
+        expect(useStreakStore.getState().loadedAt).not.toBeNull();
+
+        apiGet.mockResolvedValueOnce({ streak: streak({ current_streak: 2 }) });
+        await useStreakStore.getState().refreshStreak();
+        expect(useStreakStore.getState().streak?.current_streak).toBe(2);
+    });
+});

apps/mobile/src/components/StreakDisplay.tsx

@@ -43,12 +43,12 @@ export function streakStatus(streak: CoupleStreak): { headline: string; status:
  * Displays the couple's shared streak. The flame pulses while the streak is alive.
  */
 export function StreakDisplay({ showLongest = false, delay = 0, compact = false }: StreakDisplayProps) {
-    const { streak, fetchStreak } = useStreakStore();
+    const { streak, ensureStreakLoaded } = useStreakStore();
 
     // Fetch streak on mount
     useEffect(() => {
-        fetchStreak();
-    }, [fetchStreak]);
+        void ensureStreakLoaded();
+    }, [ensureStreakLoaded]);
 
     // Flame pulse animation
     const scale = useSharedValue(1);

apps/mobile/src/features/chat/ChatScreen.tsx

@@ -1,4 +1,4 @@
-import { useState, useEffect, useCallback } from "react";
+import { useState, useEffect, useCallback, useRef } from "react";
 import { View, StyleSheet, KeyboardAvoidingView, Platform, Alert } from "react-native";
 import { useLocalSearchParams, useRouter } from "expo-router";
 import { useFocusEffect, useIsFocused } from "@react-navigation/native";
@@ -60,20 +60,31 @@ export const ChatScreen: React.FC = () => {
 
     const isFocused = useIsFocused();
 
-    // Typing indicator hook
+    // Each hook needs a value the other produces: the message poll reports typing
+    // state, and an arriving message clears the indicator. The ref breaks the cycle.
+    const clearTypingRef = useRef<() => void>(() => undefined);
+    const handleNewMessage = useCallback(() => clearTypingRef.current(), []);
+
+    // Message subscription hook
+    const { messages, setMessages, partnerTyping: syncedTyping } = useMessageSubscription({
+        matchId,
+        userId: user?.id,
+        onNewMessage: handleNewMessage,
+        isFocused,
+    });
+
+    // Typing indicator hook, reading the state the message poll already fetched
     const { partnerTyping, sendTypingEvent, clearTypingIndicator } = useTypingIndicator({
         channelName: `chat:${matchId}`,
         matchId,
         userId: user?.id,
         isFocused,
+        externalTyping: syncedTyping,
     });
 
-    // Message subscription hook
-    const { messages, setMessages, isFocusedRef } = useMessageSubscription({
-        matchId,
-        userId: user?.id,
-        onNewMessage: clearTypingIndicator,
-    });
+    useEffect(() => {
+        clearTypingRef.current = clearTypingIndicator;
+    }, [clearTypingIndicator]);
 
 
     // Message actions hook for deletion and reporting
@@ -174,16 +185,12 @@ export const ChatScreen: React.FC = () => {
     // Track active chat to prevent notifications for current chat
     useFocusEffect(
         useCallback(() => {
-            isFocusedRef.current = true;
             if (matchId) {
                 setActiveMatchId(matchId);
                 markMatchMessagesAsRead(matchId);
                 Events.matchViewed();
             }
-            return () => {
-                isFocusedRef.current = false;
-                setActiveMatchId(null);
-            };
+            return () => setActiveMatchId(null);
         }, [matchId, setActiveMatchId, markMatchMessagesAsRead])
     );
 

apps/mobile/src/features/dares/DaresScreen.tsx

@@ -1,6 +1,7 @@
 import { useCallback, useEffect, useState } from "react";
 import { ActivityIndicator, Pressable, RefreshControl, ScrollView, StyleSheet, Text, View } from "react-native";
 import { Ionicons } from "@expo/vector-icons";
+import { useIsFocused } from "@react-navigation/native";
 import Animated, { FadeIn } from "react-native-reanimated";
 import { GradientBackground } from "../../components/ui";
 import { Paywall } from "../../components/paywall";
@@ -20,7 +21,8 @@ const TABS: { key: Tab; label: string }[] = [
 ];
 
 export function DaresScreen() {
-    const dares = useDares();
+    const isFocused = useIsFocused();
+    const dares = useDares({ isFocused });
     const [tab, setTab] = useState<Tab>("active");
     const [sheetPack, setSheetPack] = useState<DarePack | null>(null);
     const [sheetOpen, setSheetOpen] = useState(false);

apps/mobile/src/features/dares/hooks/useDares.ts

@@ -1,11 +1,21 @@
 import { useCallback, useEffect, useRef, useState } from "react";
 import { daresApi } from "../../../lib/daresApi";
 import { ApiError } from "../../../lib/apiClient";
+import { usePolling } from "../../../hooks/usePolling";
 import type { DareCatalog, DareStats, SendDarePayload, SentDare } from "../types";
 
 /** Matches the chat poll cadence; the API has no realtime channel. */
 const POLL_INTERVAL_MS = 5_000;
 
+export interface UseDaresConfig {
+    /**
+     * Supplied by the screen rather than read from navigation here, so the hook
+     * stays renderable without a navigator. Polling stops when the screen is not
+     * on top; `usePolling` additionally stops it when the app backgrounds.
+     */
+    isFocused?: boolean;
+}
+
 export interface UseDaresReturn {
     active: SentDare[];
     history: SentDare[];
@@ -25,7 +35,19 @@ export interface UseDaresReturn {
     cancel: (dareId: string) => Promise<void>;
 }
 
-export function useDares(): UseDaresReturn {
+/**
+ * Identity of the active set as the user experiences it. History, stats and the
+ * remaining-send allowance only move when a dare enters or leaves this set or
+ * changes status, so this is the signal that says the slower endpoints are worth
+ * re-reading.
+ */
+const activeSignature = (dares: SentDare[]): string =>
+    dares
+        .map(dare => `${dare.id}:${dare.status}`)
+        .sort()
+        .join("|");
+
+export function useDares({ isFocused = true }: UseDaresConfig = {}): UseDaresReturn {
     const [active, setActive] = useState<SentDare[]>([]);
     const [history, setHistory] = useState<SentDare[]>([]);
     const [catalog, setCatalog] = useState<DareCatalog | null>(null);
@@ -36,42 +58,63 @@ export function useDares(): UseDaresReturn {
     const [paywallReason, setPaywallReason] = useState<string | null>(null);
     const fetchingRef = useRef(false);
     const mountedRef = useRef(true);
+    const signatureRef = useRef<string | null>(null);
 
-    const refresh = useCallback(async () => {
+    useEffect(() => {
+        mountedRef.current = true;
+        return () => {
+            mountedRef.current = false;
+        };
+    }, []);
+
+    /**
+     * `full` reads everything; the polling path reads only the active list and
+     * follows up on the rest when that list actually changed. A failure updates
+     * the UI's error state either way, but is only rethrown for the poll path
+     * (`throwOnError`): `usePolling` needs the rejection to drive its backoff,
+     * while pull-to-refresh and post-mutation callers already surface the error
+     * themselves and must not turn it into an unhandled rejection.
+     */
+    const load = useCallback(async (full: boolean, throwOnError = false) => {
         if (fetchingRef.current) return;
         fetchingRef.current = true;
         try {
-            const [activeResult, historyResult, catalogResult, statsResult] = await Promise.all([
-                daresApi.list("active"),
+            const activeResult = await daresApi.list("active");
+            if (!mountedRef.current) return;
+            setActive(activeResult.dares);
+
+            const signature = activeSignature(activeResult.dares);
+            const changed = signature !== signatureRef.current;
+            signatureRef.current = signature;
+
+            if (full || changed) {
+                const [historyResult, catalogResult, statsResult] = await Promise.all([
                     daresApi.list("history"),
                     daresApi.catalog(),
                     daresApi.stats(),
                 ]);
                 if (!mountedRef.current) return;
-            setActive(activeResult.dares);
                 setHistory(historyResult.dares);
                 setCatalog(catalogResult);
                 setStats(statsResult);
+            }
             setError(null);
         } catch (cause) {
             if (mountedRef.current) {
                 setError(cause instanceof ApiError ? cause.message : "Could not load dares");
             }
+            if (throwOnError) throw cause;
         } finally {
             fetchingRef.current = false;
             if (mountedRef.current) setLoading(false);
         }
     }, []);
 
-    useEffect(() => {
-        mountedRef.current = true;
-        void refresh();
-        const timer = setInterval(() => void refresh(), POLL_INTERVAL_MS);
-        return () => {
-            mountedRef.current = false;
-            clearInterval(timer);
-        };
-    }, [refresh]);
+    /** Pull-to-refresh and post-mutation reloads always read the slow endpoints too. */
+    const refresh = useCallback(() => load(true), [load]);
+    const poll = useCallback(() => load(false, true), [load]);
+
+    usePolling(poll, { intervalMs: POLL_INTERVAL_MS, enabled: isFocused });
 
     /** Premium refusals steer to the paywall; everything else surfaces inline. */
     const handleFailure = useCallback((cause: unknown) => {

apps/mobile/src/features/live-draw/LiveDrawScreen.tsx

@@ -8,6 +8,7 @@ import {
   useWindowDimensions,
 } from 'react-native';
 import { useLocalSearchParams, useRouter } from 'expo-router';
+import { useIsFocused } from '@react-navigation/native';
 import { useSafeAreaInsets } from 'react-native-safe-area-context';
 import { Ionicons } from '@expo/vector-icons';
 import * as Haptics from 'expo-haptics';
@@ -35,6 +36,7 @@ export const LiveDrawScreen: React.FC = () => {
   const insets = useSafeAreaInsets();
   const { user } = useAuthStore();
   const coupleId = coupleIdParam || user?.couple_id;
+  const isFocused = useIsFocused();
   const { width: screenWidth } = useWindowDimensions();
 
   const [selectedColor, setSelectedColor] = useState(PRESET_COLORS[0]);
@@ -95,6 +97,7 @@ export const LiveDrawScreen: React.FC = () => {
   const sync = useDrawingSync({
     coupleId: coupleId!,
     userId: user?.id,
+    isFocused,
     onStrokeStart: handleStrokeStartFromPartner,
     onStrokeContinue: handleStrokeContinueFromPartner,
     onStrokeEnd: handleStrokeEndFromPartner,

apps/mobile/src/features/live-draw/hooks/useDrawingSync.ts

@@ -1,9 +1,13 @@
 import { useCallback, useEffect, useMemo, useRef } from 'react';
 import { ApiError } from '../../../lib/apiClient';
 import { appDataApi, type LiveDrawState } from '../../../lib/appDataApi';
+import { usePolling } from '../../../hooks/usePolling';
 import type { StrokeSegment, StrokePoint } from '../types';
 import { updateWidget } from '../utils/widgetBridge';
 
+/** Fast enough for a shared canvas to feel live, and only while one is on screen. */
+const POLL_INTERVAL_MS = 750;
+
 interface UseDrawingSyncConfig {
   coupleId: string;
   userId: string | undefined;
@@ -14,6 +18,12 @@ interface UseDrawingSyncConfig {
   onUndo: (strokeId: string) => void;
   onRedo: (stroke: StrokeSegment) => void;
   onLoadStrokes: (strokes: StrokeSegment[]) => void;
+  /**
+   * Supplied by the screen rather than read from navigation here, so the hook
+   * stays renderable without a navigator. A canvas nobody is looking at polls
+   * nothing; `usePolling` also stops it when the app goes to the background.
+   */
+  isFocused?: boolean;
 }
 
 interface UseDrawingSyncReturn {
@@ -52,7 +62,7 @@ export function mergeDrawingChanges(base: StrokeSegment[], desired: StrokeSegmen
 }
 
 export function useDrawingSync(config: UseDrawingSyncConfig): UseDrawingSyncReturn {
-  const { coupleId, userId, onLoadStrokes } = config;
+  const { coupleId, userId, onLoadStrokes, isFocused = true } = config;
   const revisionRef = useRef(0);
   const baselineRef = useRef<StrokeSegment[]>([]);
   const workingRef = useRef<StrokeSegment[]>([]);
@@ -132,19 +142,25 @@ export function useDrawingSync(config: UseDrawingSyncConfig): UseDrawingSyncRetu
     void appDataApi.getLiveDraw().then(acceptState).catch(error => console.error('Failed to load live drawing:', error));
   }, [coupleId, acceptState]);
 
-  useEffect(() => {
-    if (!coupleId || !userId) return;
-    let cancelled = false;
-    const poll = async () => {
+  // Our own writes already return the authoritative state, so reading over the top
+  // of one in flight would only race it back to a revision we are about to replace.
+  const poll = useCallback(async () => {
     if (pendingWritesRef.current > 0) return;
-      try {
     const state = await appDataApi.getLiveDraw();
-        if (!cancelled && state.revision > revisionRef.current) acceptState(state);
-      } catch (error) { console.error('Failed to poll live drawing:', error); }
-    };
-    const timer = setInterval(() => void poll(), 750);
-    return () => { cancelled = true; clearInterval(timer); if (throttleRef.current) clearTimeout(throttleRef.current); };
-  }, [coupleId, userId, acceptState]);
+    if (state.revision > revisionRef.current) acceptState(state);
+  }, [acceptState]);
+
+  // `leading: false` because the mount effect above already read the initial state;
+  // usePolling adds the overlap guard, backoff and background pause the raw
+  // interval had none of.
+  usePolling(poll, {
+    intervalMs: POLL_INTERVAL_MS,
+    enabled: Boolean(coupleId) && Boolean(userId) && isFocused,
+    leading: false,
+    resetKey: `${coupleId}:${userId ?? ''}`,
+  });
+
+  useEffect(() => () => { if (throttleRef.current) clearTimeout(throttleRef.current); }, []);
 
   const persistStrokes = useCallback((strokes: StrokeSegment[]) => {
     if (throttleRef.current) clearTimeout(throttleRef.current);

apps/mobile/src/features/swipe/hooks/useSwipeScreen.ts

@@ -1,7 +1,7 @@
 import { useCallback, useEffect, useRef, useState } from "react";
 import { useFocusEffect, useLocalSearchParams } from "expo-router";
 
-import { useAuthStore, usePacksStore, useStreakStore } from "../../../store";
+import { useAuthStore, usePacksStore, useResponsesStore, useStreakStore } from "../../../store";
 import { skipQuestion, getSkippedQuestionIds } from "../../../lib/skippedQuestions";
 import { ApiError, apiClient } from "../../../lib/apiClient";
 import { Events } from "../../../lib/analytics";
@@ -352,6 +352,12 @@ export const useSwipeScreen = () => {
             // wrong partner state for the rest of the session. Refreshing it must never
             // interfere with recording the answer, so it stays off the critical path.
             void useStreakStore.getState().fetchStreak().catch(() => undefined);
+
+            // This answer changed pack progress and the answer history. Marking their
+            // caches stale costs no request: whichever screen the user opens next
+            // reloads once, and the ones they do not open stay quiet.
+            usePacksStore.getState().invalidatePacks();
+            useResponsesStore.getState().invalidateResponses();
         } catch (error) {
             // A 429 means the server rejected this answer outright. Do not advance the
             // index, or the question is silently skipped and lost for the day.

apps/mobile/src/hooks/index.ts

@@ -1,4 +1,7 @@
 export { useAmbientOrbAnimation } from './useAmbientOrbAnimation';
+export { usePolling } from './usePolling';
+export type { UsePollingOptions } from './usePolling';
+export { useCoupleSync, SYNC_INTERVAL_MS } from './useCoupleSync';
 export type { AmbientOrbConfig } from './useAmbientOrbAnimation';
 export { useFeatureInterest } from './useFeatureInterest';
 export { useMediaPicker } from './useMediaPicker';

apps/mobile/src/hooks/useCoupleSync.ts

@@ -0,0 +1,116 @@
+import { useCallback, useRef } from 'react';
+import { appDataApi, type SyncSummary } from '../lib/appDataApi';
+import { useAuthStore } from '../store/authStore';
+import { useMatchStore } from '../store/matchStore';
+import { useMessageStore } from '../store/messageStore';
+import { usePacksStore } from '../store/packsStore';
+import { useStreakStore } from '../store/streakStore';
+import { usePolling } from './usePolling';
+
+/**
+ * Slower than the five-second full refresh it replaces, because the request it
+ * makes is a change summary rather than five payloads: the app reacts to a
+ * partner's action within this window, but pays one small query for it.
+ */
+export const SYNC_INTERVAL_MS = 15_000;
+
+/**
+ * Keeps cached domain data honest without re-fetching it. Each poll reads one
+ * summary of the couple's state and refreshes only the domains whose markers
+ * moved — and only the ones already on screen, so a view nobody has opened is
+ * not loaded in the background.
+ */
+export function useCoupleSync(userId: string | undefined, coupleId: string | null | undefined): void {
+    const previousRef = useRef<SyncSummary | null>(null);
+    const identityRef = useRef<string>('');
+    // `sync` is memoized on a stable callback, so `taskRef` inside usePolling
+    // never has to restart the schedule on every render; it reads the current
+    // identity through this ref instead of closing over the arguments from
+    // whichever render created it.
+    const identityValuesRef = useRef({ userId, coupleId });
+    identityValuesRef.current = { userId, coupleId };
+
+    const latestIdentity = useCallback(() => {
+        const { userId, coupleId } = identityValuesRef.current;
+        return `${userId ?? ''}:${coupleId ?? ''}`;
+    }, []);
+
+    const sync = useCallback(async () => {
+        const identity = latestIdentity();
+        if (identity !== identityRef.current) {
+            // A new account's first summary must not be diffed against the prior
+            // account's markers, or every domain would silently "refresh" on login.
+            identityRef.current = identity;
+            previousRef.current = null;
+        }
+
+        const summary = await appDataApi.syncSummary();
+        // The account can change while this request is in flight. The response
+        // describes the identity that asked for it, so once that is no longer the
+        // current one it may not touch anything: not the badge, not the baseline
+        // the next account will diff against, and not a single refresh decision.
+        // Both checks matter — `identityRef` catches a newer sync that has already
+        // started, and `latestIdentity()` catches a switch that has only rendered.
+        if (identityRef.current !== identity || latestIdentity() !== identity) return;
+
+        const previous = previousRef.current;
+        previousRef.current = summary;
+
+        // The badge count comes straight out of the summary, so keeping it current
+        // costs nothing beyond this request.
+        if (summary.unread_total !== previous?.unread_total) {
+            useMessageStore.getState().setUnreadCount(summary.unread_total);
+        }
+        // The first poll only establishes the baseline: every screen loads its own
+        // data on mount, and refreshing it again here would undo the saving.
+        if (!previous) return;
+
+        const auth = useAuthStore.getState();
+        const matchStore = useMatchStore.getState();
+        const refreshes: Promise<unknown>[] = [];
+
+        if (summary.profile_updated_at !== previous.profile_updated_at || summary.couple_id !== previous.couple_id) {
+            // fetchUser also refreshes the couple when one is set.
+            refreshes.push(auth.fetchUser());
+        } else if (summary.partner_id !== previous.partner_id || summary.partner_updated_at !== previous.partner_updated_at) {
+            refreshes.push(auth.fetchCouple());
+        }
+
+        if (matchStore.loadedAt.active !== undefined && (
+            summary.match_count !== previous.match_count ||
+            summary.new_match_count !== previous.new_match_count ||
+            summary.latest_match_at !== previous.latest_match_at ||
+            // Neither count moves when a partner edits an existing match's type or
+            // response summary through response editing.
+            summary.match_state_fingerprint !== previous.match_state_fingerprint ||
+            // `unread_total` can hold steady while unread redistributes between
+            // matches (one read, another receives a message), which reorders the
+            // unread-first list without moving the total.
+            summary.match_unread_fingerprint !== previous.match_unread_fingerprint)) {
+            refreshes.push(matchStore.fetchMatches(true, { silent: true }));
+        }
+        if (matchStore.loadedAt.pending !== undefined && summary.pending_yours !== previous.pending_yours) {
+            refreshes.push(matchStore.fetchPendingQuestions({ silent: true }));
+        }
+        if (matchStore.loadedAt.their_turn !== undefined && summary.pending_theirs !== previous.pending_theirs) {
+            refreshes.push(matchStore.fetchTheirTurnQuestions({ silent: true }));
+        }
+        // Only refresh a domain the user has actually opened, matching the rule
+        // that unopened domains stay unloaded.
+        if (usePacksStore.getState().enabledPacksLoadedAt !== null
+            && summary.enabled_packs_fingerprint !== previous.enabled_packs_fingerprint) {
+            refreshes.push(usePacksStore.getState().fetchEnabledPacks());
+        }
+        if (summary.streak_updated_at !== previous.streak_updated_at) {
+            refreshes.push(useStreakStore.getState().refreshStreak());
+        }
+
+        await Promise.allSettled(refreshes);
+    }, [latestIdentity]);
+
+    usePolling(sync, {
+        intervalMs: SYNC_INTERVAL_MS,
+        enabled: Boolean(userId),
+        resetKey: `${userId ?? ''}:${coupleId ?? ''}`,
+    });
+}

apps/mobile/src/hooks/useMessageSubscription.ts

@@ -1,5 +1,6 @@
 import { useCallback, useEffect, useRef, useState } from 'react';
-import { chatApi } from '../lib/chatApi';
+import { chatApi, type MessagesPage } from '../lib/chatApi';
+import { usePolling } from './usePolling';
 import type { Message } from '../features/chat/types';
 
 export interface UseMessageSubscriptionConfig {
@@ -7,51 +8,115 @@ export interface UseMessageSubscriptionConfig {
     userId: string | undefined;
     onNewMessage?: () => void;
     pollInterval?: number;
+    /** Whether the chat is on screen. Polling and read receipts stop when it is not. */
+    isFocused?: boolean;
 }
 
 export interface UseMessageSubscriptionReturn {
     messages: Message[];
     setMessages: React.Dispatch<React.SetStateAction<Message[]>>;
     loading: boolean;
-    isFocusedRef: React.MutableRefObject<boolean>;
+    /** Partner typing state folded into the message poll; undefined until the server reports it. */
+    partnerTyping: boolean | undefined;
+    /** Fetches the next delta now, e.g. straight after sending. */
+    refresh: () => Promise<void>;
 }
 
-/** Authenticated API polling replaces Supabase Realtime for self-hosted chat. */
-export const useMessageSubscription = ({ matchId, userId, onNewMessage, pollInterval = 1_500 }: UseMessageSubscriptionConfig): UseMessageSubscriptionReturn => {
+const timeOf = (message: Message): number => {
+    const parsed = message.created_at ? Date.parse(message.created_at) : Number.NaN;
+    return Number.isNaN(parsed) ? 0 : parsed;
+};
+
+/** Newest first, matching the order the API returns a snapshot in. */
+const byNewest = (a: Message, b: Message): number => {
+    const delta = timeOf(b) - timeOf(a);
+    if (delta !== 0) return delta;
+    return a.id < b.id ? 1 : a.id > b.id ? -1 : 0;
+};
+
+/**
+ * Returns the previous array unchanged when a delta carries nothing, so an idle
+ * poll re-renders neither this hook's consumers nor the message list.
+ */
+export const mergeMessagePage = (previous: Message[], page: MessagesPage): Message[] => {
+    if (page.complete !== false) return page.messages;
+    const removed = page.removed_ids ?? [];
+    if (page.messages.length === 0 && removed.length === 0) return previous;
+
+    const byId = new Map(previous.map(message => [message.id, message]));
+    for (const message of page.messages) byId.set(message.id, message);
+    for (const id of removed) byId.delete(id);
+    return [...byId.values()].sort(byNewest);
+};
+
+/**
+ * Authenticated API polling replaces Supabase Realtime for self-hosted chat.
+ *
+ * Each poll asks only for what changed since the cursor the server issued last
+ * time, so an idle conversation costs an all-but-empty response instead of the
+ * five hundred messages the screen already has. Read receipts are written only
+ * when the response actually contains an unread message from the partner, which
+ * on an idle chat is never.
+ */
+export const useMessageSubscription = ({
+    matchId,
+    userId,
+    onNewMessage,
+    pollInterval = 2_000,
+    isFocused = true,
+}: UseMessageSubscriptionConfig): UseMessageSubscriptionReturn => {
     const [messages, setMessages] = useState<Message[]>([]);
-    const [loading, setLoading] = useState(true);
-    const isFocusedRef = useRef(false);
+    const [loading, setLoading] = useState(Boolean(matchId && userId));
+    const [partnerTyping, setPartnerTyping] = useState<boolean | undefined>(undefined);
+    const sinceRef = useRef<string | null>(null);
     const knownIdsRef = useRef<Set<string>>(new Set());
-    const fetchingRef = useRef(false);
+    const loadingRef = useRef(true);
+    const notifyRef = useRef(onNewMessage);
+    notifyRef.current = onNewMessage;
 
-    const refresh = useCallback(async (initial = false) => {
-        if (!matchId || !userId || fetchingRef.current) return;
-        fetchingRef.current = true;
+    // A different conversation shares none of this one's state, and the poll below
+    // restarts on the same key so the new one loads immediately.
+    useEffect(() => {
+        sinceRef.current = null;
+        knownIdsRef.current = new Set();
+        loadingRef.current = Boolean(matchId && userId);
+        setMessages([]);
+        setPartnerTyping(undefined);
+        setLoading(loadingRef.current);
+    }, [matchId, userId]);
+
+    const refresh = useCallback(async () => {
+        if (!matchId || !userId) return;
+        const since = sinceRef.current;
         try {
-            const response = await chatApi.listMessages(matchId);
-            const partnerArrived = !initial && response.messages.some(message => message.user_id !== userId && !knownIdsRef.current.has(message.id));
-            knownIdsRef.current = new Set(response.messages.map(message => message.id));
-            setMessages(response.messages);
-            if (isFocusedRef.current) await chatApi.markRead(matchId);
-            if (partnerArrived) onNewMessage?.();
+            const page = await chatApi.listMessages(matchId, { ...(since ? { since } : {}), typing: true });
+            // Without a cursor the server cannot answer with deltas, so keep asking
+            // for snapshots rather than silently freezing on a stale page.
+            sinceRef.current = page.server_time ?? null;
+            if (page.typing) setPartnerTyping(page.typing.typing);
+
+            const arrivals = page.messages.filter(message => message.user_id !== userId && !knownIdsRef.current.has(message.id));
+            for (const message of page.messages) knownIdsRef.current.add(message.id);
+            for (const id of page.removed_ids ?? []) knownIdsRef.current.delete(id);
+            setMessages(previous => mergeMessagePage(previous, page));
+
+            if (isFocused && page.messages.some(message => message.user_id !== userId && !message.read_at)) {
+                await chatApi.markRead(matchId);
+            }
+            if (!loadingRef.current && arrivals.length > 0) notifyRef.current?.();
         } finally {
-            fetchingRef.current = false;
-            if (initial) setLoading(false);
+            if (loadingRef.current) {
+                loadingRef.current = false;
+                setLoading(false);
             }
-    }, [matchId, userId, onNewMessage]);
+        }
+    }, [matchId, userId, isFocused]);
 
-    useEffect(() => {
-        if (!matchId || !userId) {
-            setMessages([]);
-            setLoading(false);
-            return;
-        }
-        setLoading(true);
-        knownIdsRef.current = new Set();
-        void refresh(true).catch(() => undefined);
-        const timer = setInterval(() => void refresh(false).catch(() => undefined), pollInterval);
-        return () => clearInterval(timer);
-    }, [matchId, userId, pollInterval, refresh]);
+    usePolling(refresh, {
+        intervalMs: pollInterval,
+        enabled: Boolean(matchId && userId && isFocused),
+        resetKey: `${matchId ?? ''}:${userId ?? ''}`,
+    });
 
-    return { messages, setMessages, loading, isFocusedRef };
+    return { messages, setMessages, loading, partnerTyping, refresh };
 };

apps/mobile/src/hooks/usePolling.ts

@@ -0,0 +1,92 @@
+import { useEffect, useRef } from 'react';
+import { isForeground, subscribeToForeground } from '../lib/appForeground';
+
+export interface UsePollingOptions {
+    intervalMs: number;
+    /** Caller-owned relevance: screen focus, a loaded id, a paired couple. */
+    enabled?: boolean;
+    /** Run once as soon as polling becomes active. Default true. */
+    leading?: boolean;
+    /** Ceiling for the exponential backoff applied after consecutive failures. */
+    maxIntervalMs?: number;
+    /**
+     * Restarts the schedule when it changes, so a caller that switches subject —
+     * a different chat, a different couple — gets an immediate run instead of
+     * waiting out the interval left over from the previous one.
+     */
+    resetKey?: string | number;
+}
+
+/**
+ * A recurring task with the three properties every poller in this app needs and
+ * none of them had: it stops while the app is backgrounded, it never runs twice
+ * concurrently, and it backs off instead of hammering an API that is failing.
+ *
+ * The next run is scheduled after the previous one settles rather than on a fixed
+ * `setInterval`, so a slow response delays the next request instead of queueing
+ * one behind it. `task` is read through a ref, so a caller may pass a fresh
+ * closure every render without restarting the schedule.
+ */
+export function usePolling(task: () => Promise<void>, options: UsePollingOptions): void {
+    const { intervalMs, enabled = true, leading = true, maxIntervalMs = intervalMs * 8, resetKey } = options;
+    const taskRef = useRef(task);
+    taskRef.current = task;
+
+    useEffect(() => {
+        if (!enabled) return;
+        let cancelled = false;
+        let running = false;
+        let failures = 0;
+        let foreground = isForeground();
+        let timer: ReturnType<typeof setTimeout> | null = null;
+
+        const clear = () => {
+            if (timer !== null) {
+                clearTimeout(timer);
+                timer = null;
+            }
+        };
+        const schedule = () => {
+            if (cancelled || !foreground || timer !== null) return;
+            const delay = Math.min(intervalMs * 2 ** failures, maxIntervalMs);
+            timer = setTimeout(() => {
+                timer = null;
+                void run();
+            }, delay);
+        };
+        const run = async () => {
+            if (cancelled || running || !foreground) return;
+            running = true;
+            try {
+                await taskRef.current();
+                failures = 0;
+            } catch {
+                failures += 1;
+            } finally {
+                running = false;
+                schedule();
+            }
+        };
+        const unsubscribe = subscribeToForeground((next) => {
+            if (next === foreground) return;
+            foreground = next;
+            if (!foreground) {
+                clear();
+                return;
+            }
+            // Back from the background: the cached data is as stale as the absence
+            // was long, so catch up now rather than after another full interval.
+            failures = 0;
+            void run();
+        });
+
+        if (leading) void run();
+        else schedule();
+
+        return () => {
+            cancelled = true;
+            clear();
+            unsubscribe();
+        };
+    }, [enabled, intervalMs, leading, maxIntervalMs, resetKey]);
+}

apps/mobile/src/hooks/useTypingIndicator.ts

@@ -1,5 +1,6 @@
 import { useCallback, useEffect, useRef, useState } from 'react';
 import { chatApi } from '../lib/chatApi';
+import { usePolling } from './usePolling';
 
 export interface UseTypingIndicatorConfig {
     channelName: string;
@@ -9,6 +10,12 @@ export interface UseTypingIndicatorConfig {
     isFocused?: boolean;
     throttleInterval?: number;
     pollInterval?: number;
+    /**
+     * Typing state already known from another request. When supplied this hook
+     * stops polling for it, which is how the chat screen gets typing state for
+     * free out of the message poll instead of a second request every interval.
+     */
+    externalTyping?: boolean | undefined;
 }
 
 export interface UseTypingIndicatorReturn {
@@ -17,31 +24,43 @@ export interface UseTypingIndicatorReturn {
     clearTypingIndicator: () => void;
 }
 
-export const useTypingIndicator = ({ channelName, userId, matchId = channelName.replace(/^chat:/, ''), isFocused = true, throttleInterval = 2_000, pollInterval = 1_500 }: UseTypingIndicatorConfig): UseTypingIndicatorReturn => {
+export const useTypingIndicator = ({
+    channelName,
+    userId,
+    matchId = channelName.replace(/^chat:/, ''),
+    isFocused = true,
+    throttleInterval = 2_000,
+    pollInterval = 1_500,
+    externalTyping,
+}: UseTypingIndicatorConfig): UseTypingIndicatorReturn => {
     const [partnerTyping, setPartnerTyping] = useState(false);
     const lastTypingEventRef = useRef(0);
+    const external = externalTyping !== undefined;
 
     useEffect(() => {
-        if (!matchId || !userId || !isFocused) {
-            setPartnerTyping(false);
-            return;
-        }
-        let active = true;
-        const poll = async () => {
+        if (externalTyping !== undefined) setPartnerTyping(externalTyping);
+    }, [externalTyping]);
+
+    // Losing the subject stops both sources of truth, so drop the stale indicator
+    // rather than leaving the partner typing forever in a chat nobody is watching.
+    useEffect(() => {
+        if (!matchId || !userId || !isFocused) setPartnerTyping(false);
+    }, [matchId, userId, isFocused]);
+
+    const poll = useCallback(async () => {
         try {
             const state = await chatApi.getTyping(matchId);
-                if (active) setPartnerTyping(state.typing);
+            setPartnerTyping(state.typing);
         } catch {
-                if (active) setPartnerTyping(false);
+            setPartnerTyping(false);
         }
-        };
-        void poll();
-        const timer = setInterval(() => void poll(), pollInterval);
-        return () => {
-            active = false;
-            clearInterval(timer);
-        };
-    }, [matchId, userId, isFocused, pollInterval]);
+    }, [matchId]);
+
+    usePolling(poll, {
+        intervalMs: pollInterval,
+        enabled: !external && Boolean(matchId) && Boolean(userId) && isFocused,
+        resetKey: matchId,
+    });
 
     const sendTypingEvent = useCallback(() => {
         if (!matchId || !userId) return;

apps/mobile/src/lib/appDataApi.ts

@@ -10,7 +10,36 @@ export interface LiveDrawState {
   updated_by: string | null;
 }
 
+/**
+ * A change summary, not a payload: markers the client compares against the ones
+ * it saw last time to decide which domain, if any, is worth refetching. It
+ * replaces a periodic full refresh of profile, couple, matches, pending
+ * questions, packs and unread counts with one small request.
+ */
+export interface SyncSummary {
+  server_time: string;
+  couple_id: string | null;
+  profile_updated_at: string | null;
+  partner_id: string | null;
+  partner_updated_at: string | null;
+  match_count: number;
+  new_match_count: number;
+  latest_match_at: string | null;
+  pending_yours: number;
+  pending_theirs: number;
+  unread_total: number;
+  /** couple_packs carries no timestamp, so equal-and-opposite toggles are caught by a digest. */
+  enabled_packs_fingerprint: string | null;
+  /** Digest of each visible match's type and response summary; moves on an in-place response edit that the count/latest-at markers miss. */
+  match_state_fingerprint: string;
+  /** Digest of each visible match's unread count; moves when unread redistributes between matches without changing the total. */
+  match_unread_fingerprint: string;
+  /** couple_streaks.updated_at, so a partner's answer can silently refresh an already-loaded streak. */
+  streak_updated_at: string | null;
+}
+
 export const appDataApi = {
+  syncSummary: () => apiClient.get<SyncSummary>('/v1/me/sync'),
   packContext: (packId: string) => apiClient.get<{ pack: { id: string; name: string; icon: string | null } }>(`/v1/packs/${encodeURIComponent(packId)}/context`),
   packQuestions: (packId: string) => apiClient.get<{ questions: Question[] }>(`/v1/packs/${encodeURIComponent(packId)}/questions`),
   packTeaser: (packId: string) => apiClient.get<{ questions: Array<{ id: string; text: string; intensity: number }> }>(`/v1/packs/${encodeURIComponent(packId)}/teaser`),

apps/mobile/src/lib/appForeground.ts

@@ -0,0 +1,21 @@
+import { AppState, type AppStateStatus } from 'react-native';
+
+/**
+ * `background` is a real suspension and `inactive` is the moment behind the app
+ * switcher, a call, or a system prompt. Anything else — including states a test
+ * harness never sets — counts as foreground, so recurring work fails towards
+ * running rather than towards being silently disabled forever.
+ */
+export function isForegroundState(state: AppStateStatus | string | undefined): boolean {
+    return state !== 'background' && state !== 'inactive';
+}
+
+export function isForeground(): boolean {
+    return isForegroundState(AppState.currentState as AppStateStatus | undefined);
+}
+
+/** Reports the new foreground flag on every transition. Returns an unsubscribe. */
+export function subscribeToForeground(onChange: (foreground: boolean) => void): () => void {
+    const subscription = AppState.addEventListener('change', (state) => onChange(isForegroundState(state)));
+    return () => subscription.remove();
+}

apps/mobile/src/lib/chatApi.ts

@@ -1,8 +1,40 @@
 import { apiClient } from './apiClient';
 import type { Message, ReportReason } from '../features/chat/types';
 
+export interface PartnerTyping {
+    typing: boolean;
+    expires_at: string | null;
+}
+
+/**
+ * A snapshot when `complete`, otherwise only what changed since the cursor the
+ * previous page handed back. Delta rows are whole messages, not patches, so a
+ * caller merges them by id without a second shape to understand.
+ */
+export interface MessagesPage {
+    messages: Message[];
+    /** Messages the caller deleted for themselves since the cursor. */
+    removed_ids?: string[];
+    /** Cursor to send as `since` on the next poll. */
+    server_time?: string;
+    complete?: boolean;
+    /** Present when requested, saving a separate typing request. */
+    typing?: PartnerTyping;
+}
+
+export interface ListMessagesOptions {
+    since?: string;
+    typing?: boolean;
+}
+
 export const chatApi = {
-    listMessages: (matchId: string) => apiClient.get<{ messages: Message[] }>(`/v1/matches/${encodeURIComponent(matchId)}/messages`),
+    listMessages: (matchId: string, options: ListMessagesOptions = {}) => {
+        const query: string[] = [];
+        if (options.since) query.push(`since=${encodeURIComponent(options.since)}`);
+        if (options.typing) query.push('typing=true');
+        const suffix = query.length > 0 ? `?${query.join('&')}` : '';
+        return apiClient.get<MessagesPage>(`/v1/matches/${encodeURIComponent(matchId)}/messages${suffix}`);
+    },
     sendText: (matchId: string, content: string) => apiClient.post<{ message: Message }>(`/v1/matches/${encodeURIComponent(matchId)}/messages`, { content }),
     unread: () => apiClient.get<{ total: number; by_match: Record<string, number> }>('/v1/chat/unread'),
     markRead: (matchId: string) => apiClient.post<{ updated: number; read_at: string }>(`/v1/matches/${encodeURIComponent(matchId)}/read`),
@@ -11,5 +43,5 @@ export const chatApi = {
     deleteForEveryone: (messageId: string) => apiClient.delete<{ deleted: true; message: Message }>(`/v1/messages/${encodeURIComponent(messageId)}?scope=everyone`),
     report: (messageId: string, reason: ReportReason) => apiClient.post<{ reported: true }>(`/v1/messages/${encodeURIComponent(messageId)}/reports`, { reason }),
     setTyping: (matchId: string) => apiClient.put<{ typing: true }>(`/v1/matches/${encodeURIComponent(matchId)}/typing`),
-    getTyping: (matchId: string) => apiClient.get<{ typing: boolean; expires_at: string | null }>(`/v1/matches/${encodeURIComponent(matchId)}/typing`),
+    getTyping: (matchId: string) => apiClient.get<PartnerTyping>(`/v1/matches/${encodeURIComponent(matchId)}/typing`),
 };

apps/mobile/src/store/authStore.ts

@@ -34,7 +34,8 @@ const getOtherStores = () => {
     const { useSubscriptionStore } = require("./subscriptionStore");
     const { useNotificationPreferencesStore } = require("./notificationPreferencesStore");
     const { useStreakStore } = require("./streakStore");
-    return { useMatchStore, usePacksStore, useMessageStore, useSubscriptionStore, useNotificationPreferencesStore, useStreakStore };
+    const { useResponsesStore } = require("./responsesStore");
+    return { useMatchStore, usePacksStore, useMessageStore, useSubscriptionStore, useNotificationPreferencesStore, useStreakStore, useResponsesStore };
 };
 
 
@@ -87,13 +88,14 @@ export const useAuthStore = create<AuthState>((set, get) => ({
             if (error instanceof ApiError && error.status === 401) {
                 console.log("[Auth] Session rejected by API, signing out");
                 set({ user: null, couple: null, partner: null, isAuthenticated: false, isAnonymous: false, isLoading: false });
-                const { useMatchStore, usePacksStore, useMessageStore, useSubscriptionStore, useNotificationPreferencesStore, useStreakStore } = getOtherStores();
+                const { useMatchStore, usePacksStore, useMessageStore, useSubscriptionStore, useNotificationPreferencesStore, useStreakStore, useResponsesStore } = getOtherStores();
                 useMatchStore.getState().clearMatches();
                 usePacksStore.getState().clearPacks();
                 useMessageStore.getState().clearMessages();
                 useSubscriptionStore.getState().clearSubscription();
                 useNotificationPreferencesStore.getState().clearPreferences();
                 useStreakStore.getState().clearStreak();
+                useResponsesStore.getState().clearResponses();
                 await authClient.auth.signOut();
                 return;
             }
@@ -142,13 +144,14 @@ export const useAuthStore = create<AuthState>((set, get) => ({
              isLoading: false,
          });
         // Clear other stores
-        const { useMatchStore, usePacksStore, useMessageStore, useSubscriptionStore, useNotificationPreferencesStore, useStreakStore } = getOtherStores();
+        const { useMatchStore, usePacksStore, useMessageStore, useSubscriptionStore, useNotificationPreferencesStore, useStreakStore, useResponsesStore } = getOtherStores();
         useMatchStore.getState().clearMatches();
         usePacksStore.getState().clearPacks();
         useMessageStore.getState().clearMessages();
         useSubscriptionStore.getState().clearSubscription();
         useNotificationPreferencesStore.getState().clearPreferences();
         useStreakStore.getState().clearStreak();
+        useResponsesStore.getState().clearResponses();
 
         // Clear badge on sign out
         const { clearBadge } = require("../lib/badge");
@@ -173,13 +176,14 @@ export const useAuthStore = create<AuthState>((set, get) => ({
         });
         // Clear other stores when user signs out
         if (user === null) {
-            const { useMatchStore, usePacksStore, useMessageStore, useSubscriptionStore, useNotificationPreferencesStore, useStreakStore } = getOtherStores();
+            const { useMatchStore, usePacksStore, useMessageStore, useSubscriptionStore, useNotificationPreferencesStore, useStreakStore, useResponsesStore } = getOtherStores();
             useMatchStore.getState().clearMatches();
             usePacksStore.getState().clearPacks();
             useMessageStore.getState().clearMessages();
             useSubscriptionStore.getState().clearSubscription();
             useNotificationPreferencesStore.getState().clearPreferences();
             useStreakStore.getState().clearStreak();
+            useResponsesStore.getState().clearResponses();
             // Clear badge on sign out
             const { clearBadge } = require("../lib/badge");
             clearBadge();

apps/mobile/src/store/matchStore.ts

@@ -15,6 +15,20 @@ export interface PendingQuestion {
 
 type MatchViewType = 'active' | 'archived' | 'pending' | 'their_turn';
 
+/**
+ * A refresh that must not disturb what the user is looking at: no spinner, and
+ * the cached rows stay on screen until the replacement arrives.
+ */
+export interface FetchOptions { silent?: boolean }
+
+// Overlap protection lives outside the store because the loading flags are now
+// presentational — a silent refresh sets none of them and still must not run twice.
+// Keyed to the generation that started the request (see `generation` below) rather
+// than a bare presence check: a stale generation's entry must not block the next
+// account's request for the same key, and a stale generation's `finally` must not
+// clear an entry a newer generation just claimed.
+const inFlight = new Map<string, number>();
+
 // Rate limit: 12 hours in milliseconds
 const NUDGE_COOLDOWN_MS = 12 * 60 * 60 * 1000;
 
@@ -32,6 +46,8 @@ interface MatchState {
     newMatchesCount: number;
     totalCount: number | null;
     isLoading: boolean;
+    /** A user-initiated refresh over data already on screen; drives pull-to-refresh only. */
+    isRefreshing: boolean;
     isLoadingMore: boolean;
     page: number;
     hasMore: boolean;
@@ -48,11 +64,23 @@ interface MatchState {
     theirTurnQuestions: PendingQuestion[];
     isLoadingTheirTurn: boolean;
     currentView: MatchViewType;
+    /**
+     * When each view last loaded successfully. Tracked separately from the row
+     * arrays because an empty view is still a loaded view, and revisiting one
+     * must not refetch.
+     */
+    loadedAt: Partial<Record<MatchViewType, number>>;
     // Nudge state
     nudgeCooldownUntil: Date | null;
     isNudging: boolean;
+    /**
+     * Bumped on every clear (sign-out/account switch). A fetch captures this before
+     * it starts and checks it again before writing its result, so a response that
+     * outlives the clear cannot land in the next account's store.
+     */
+    generation: number;
     // Methods
-    fetchMatches: (refresh?: boolean) => Promise<void>;
+    fetchMatches: (refresh?: boolean, options?: FetchOptions) => Promise<void>;
     markAsSeen: (matchId: string) => Promise<void>;
     markAllAsSeen: () => Promise<void>;
     addMatch: (match: Match) => void;
@@ -61,13 +89,14 @@ interface MatchState {
     // Archive methods
     archiveMatch: (matchId: string) => Promise<void>;
     unarchiveMatch: (matchId: string) => Promise<void>;
-    fetchArchivedMatches: () => Promise<void>;
+    fetchArchivedMatches: (options?: FetchOptions) => Promise<void>;
     toggleShowArchived: () => void;
     isMatchArchived: (matchId: string) => boolean;
     // Pending methods
-    fetchPendingQuestions: () => Promise<void>;
-    fetchTheirTurnQuestions: () => Promise<void>;
+    fetchPendingQuestions: (options?: FetchOptions) => Promise<void>;
+    fetchTheirTurnQuestions: (options?: FetchOptions) => Promise<void>;
     setCurrentView: (view: MatchViewType) => void;
+    ensureViewLoaded: (view?: MatchViewType) => void;
     // Nudge methods
     sendNudge: () => Promise<{ success: boolean; notificationSent: boolean }>;
     checkNudgeCooldown: () => Promise<void>;
@@ -78,6 +107,7 @@ export const useMatchStore = create<MatchState>((set, get) => ({
     newMatchesCount: 0,
     totalCount: null,
     isLoading: false,
+    isRefreshing: false,
     isLoadingMore: false,
     page: 0,
     hasMore: true,
@@ -94,40 +124,53 @@ export const useMatchStore = create<MatchState>((set, get) => ({
     theirTurnQuestions: [],
     isLoadingTheirTurn: false,
     currentView: 'pending' as MatchViewType,
+    loadedAt: {},
     // Nudge state
     nudgeCooldownUntil: null,
     isNudging: false,
+    generation: 0,
 
-    fetchMatches: async (refresh = false) => {
-        const userId = useAuthStore.getState().user?.id;
+    fetchMatches: async (refresh = false, options = {}) => {
         const coupleId = useAuthStore.getState().user?.couple_id;
+        const myGeneration = get().generation;
 
         // Early return if no couple - user isn't paired yet
         if (!coupleId) {
-            set({ matches: [], newMatchesCount: 0, totalCount: 0, isLoading: false });
+            set({ matches: [], newMatchesCount: 0, totalCount: 0, isLoading: false, isRefreshing: false });
             return;
         }
 
         const state = get();
-        if (state.isLoading || (state.isLoadingMore && !refresh)) return;
+        if (inFlight.get('active') === myGeneration || (state.isLoadingMore && !refresh)) return;
 
+        // Nothing on screen yet is the only case that warrants blanking the list
+        // for a spinner; every other refresh leaves the cached rows in place.
+        const initial = state.loadedAt.active === undefined;
         if (refresh) {
-            set({ isLoading: true, error: null, page: 0, hasMore: true });
+            set({ isLoading: initial, isRefreshing: !initial && !options.silent, error: null, page: 0, hasMore: true });
         } else {
             if (!state.hasMore) return;
             set({ isLoadingMore: true });
         }
 
+        inFlight.set('active', myGeneration);
         try {
             const currentPage = refresh ? 0 : state.page;
-            const result = await apiClient.get<{ matches: Match[]; totalCount: number }>(`/v1/matches?page=${currentPage}&limit=${BATCH_SIZE}`);
+            const result = await apiClient.get<{ matches: Match[]; totalCount: number | null; hasMore?: boolean }>(`/v1/matches?page=${currentPage}&limit=${BATCH_SIZE}`);
+            // A sign-out/account switch that happened while this request was in
+            // flight must not let its response populate the next account's store.
+            if (get().generation !== myGeneration) return;
             const nonArchivedMatches = result.matches;
             const totalCount = result.totalCount;
             const archivedMatchIds = state.archivedMatchIds;
+            // The API reports this by reading one row past the page; the length
+            // comparison is only a fallback for an older server.
+            const hasMore = result.hasMore ?? nonArchivedMatches.length === BATCH_SIZE;
+            const loadedAt = { ...state.loadedAt, active: Date.now() };
 
             if (nonArchivedMatches.length === 0) {
                  if (refresh) {
-                    set({ matches: [], newMatchesCount: 0, totalCount: totalCount ?? 0, isLoading: false, hasMore: false, archivedMatchIds });
+                    set({ matches: [], newMatchesCount: 0, totalCount: totalCount ?? 0, isLoading: false, isRefreshing: false, hasMore: false, archivedMatchIds, loadedAt });
                 } else {
                     set({ isLoadingMore: false, hasMore: false });
                 }
@@ -154,22 +197,34 @@ export const useMatchStore = create<MatchState>((set, get) => ({
                 return {
                 matches: mergedMatches,
                 newMatchesCount: refresh ? newMatchesInBatch : state.newMatchesCount + newMatchesInBatch,
-                totalCount: refresh ? totalCount : state.totalCount,
+                // Later pages no longer carry a total, so keep the one the refresh recorded.
+                totalCount: refresh ? totalCount ?? state.totalCount : state.totalCount,
                 isLoading: false,
+                isRefreshing: false,
                 isLoadingMore: false,
                 page: currentPage + 1,
-                hasMore: nonArchivedMatches.length === BATCH_SIZE,
+                hasMore,
                 archivedMatchIds: refresh ? archivedMatchIds : state.archivedMatchIds,
+                loadedAt,
                 };
             });
         } catch (err) {
+            if (get().generation !== myGeneration) return;
             console.error("Error fetching matches:", err);
-            set({ error: "Failed to load matches", isLoading: false, isLoadingMore: false });
+            set({ error: "Failed to load matches", isLoading: false, isRefreshing: false, isLoadingMore: false });
+        } finally {
+            // An old generation's cleanup must not delete a newer generation's guard.
+            if (inFlight.get('active') === myGeneration) inFlight.delete('active');
         }
     },
 
     markAsSeen: async (matchId) => {
+        const myGeneration = get().generation;
         await apiClient.patch("/v1/matches/seen", { ids: [matchId] });
+        // A clear while this was in flight leaves an empty list behind, and the
+        // recount below would write that emptiness — and a zero badge — over
+        // whatever the next account has already loaded.
+        if (get().generation !== myGeneration) return;
 
         const matches = get().matches.map((m) =>
             m.id === matchId ? { ...m, is_new: false } : m
@@ -179,11 +234,13 @@ export const useMatchStore = create<MatchState>((set, get) => ({
     },
 
     markAllAsSeen: async () => {
+        const myGeneration = get().generation;
         const newMatches = get().matches.filter((m) => m.is_new);
         if (newMatches.length === 0) return;
 
         const newMatchIds = newMatches.map((m) => m.id);
         await apiClient.patch("/v1/matches/seen", { ids: newMatchIds });
+        if (get().generation !== myGeneration) return;
 
         const matches = get().matches.map((m) =>
             m.is_new ? { ...m, is_new: false } : m
@@ -210,11 +267,12 @@ export const useMatchStore = create<MatchState>((set, get) => ({
     },
 
 clearMatches: () => {
-        set({
+        set((state) => ({
             matches: [],
             newMatchesCount: 0,
             totalCount: null,
             isLoading: false,
+            isRefreshing: false,
             error: null,
             page: 0,
             hasMore: true,
@@ -228,9 +286,16 @@ clearMatches: () => {
             theirTurnQuestions: [],
             isLoadingTheirTurn: false,
             currentView: 'pending',
+            loadedAt: {},
             nudgeCooldownUntil: null,
             isNudging: false,
-        });
+            // Invalidates any request already in flight: its generation check will
+            // fail and it will not be able to write into the next account's store.
+            generation: state.generation + 1,
+        }));
+        // A request belonging to the signed-out user must not suppress the next
+        // one: the guard is a duplicate-request check, not a lock on the data.
+        inFlight.clear();
     },
 
     // Archive methods
@@ -240,6 +305,7 @@ clearMatches: () => {
 
         // Optimistically update UI
         const state = get();
+        const myGeneration = state.generation;
         const matchToArchive = state.matches.find(m => m.id === matchId);
 
         if (matchToArchive) {
@@ -258,7 +324,11 @@ clearMatches: () => {
             await apiClient.put(`/v1/matches/${matchId}/archive`, { archived: true });
         } catch (error) {
             console.error("Error archiving match:", error);
-            // Revert on error
+            // Revert on error — but only into the store the optimistic update was
+            // applied to. After an account switch the row it would restore belongs
+            // to the previous couple, and putting it back would show one couple's
+            // match inside another's list.
+            if (get().generation !== myGeneration) return;
             if (matchToArchive) {
                 const revertArchivedIds = new Set(get().archivedMatchIds);
                 revertArchivedIds.delete(matchId);
@@ -279,6 +349,7 @@ clearMatches: () => {
 
         // Optimistically update UI
         const state = get();
+        const myGeneration = state.generation;
         const matchToUnarchive = state.archivedMatches.find(m => m.id === matchId);
 
         if (matchToUnarchive) {
@@ -297,7 +368,8 @@ clearMatches: () => {
             await apiClient.put(`/v1/matches/${matchId}/archive`, { archived: false });
         } catch (error) {
             console.error("Error unarchiving match:", error);
-            // Revert on error
+            // Revert on error, and only for the account that started it.
+            if (get().generation !== myGeneration) return;
             if (matchToUnarchive) {
                 const revertArchivedIds = new Set(get().archivedMatchIds);
                 revertArchivedIds.add(matchId);
@@ -312,34 +384,35 @@ clearMatches: () => {
         }
     },
 
-    fetchArchivedMatches: async () => {
+    fetchArchivedMatches: async (options = {}) => {
         const userId = useAuthStore.getState().user?.id;
         const coupleId = useAuthStore.getState().user?.couple_id;
 
         if (!coupleId || !userId) return;
 
+        const myGeneration = get().generation;
         const state = get();
-        if (state.isLoadingArchived) return;
-
-        set({ isLoadingArchived: true });
+        if (inFlight.get('archived') === myGeneration) return;
+        if (!options.silent || state.loadedAt.archived === undefined) set({ isLoadingArchived: true });
 
+        inFlight.set('archived', myGeneration);
         try {
-            const result = await apiClient.get<{matches:Match[];totalCount:number}>(`/v1/matches?archived=true&limit=100`);
+            const result = await apiClient.get<{matches:Match[];totalCount:number | null}>(`/v1/matches?archived=true&limit=100`);
+            if (get().generation !== myGeneration) return;
             const archivedMatches = result.matches;
             const archivedIds = archivedMatches.map(match => match.id);
-            if (archivedMatches.length === 0) {
-                set({ archivedMatches: [], isLoadingArchived: false });
-                return;
-            }
-
-            set({
+            set((current) => ({
                 archivedMatches,
                 isLoadingArchived: false,
                 archivedMatchIds: new Set(archivedIds),
-            });
+                loadedAt: { ...current.loadedAt, archived: Date.now() },
+            }));
         } catch (err) {
+            if (get().generation !== myGeneration) return;
             console.error("Error fetching archived matches:", err);
             set({ isLoadingArchived: false });
+        } finally {
+            if (inFlight.get('archived') === myGeneration) inFlight.delete('archived');
         }
     },
 
@@ -350,8 +423,8 @@ clearMatches: () => {
         set({ showArchived: newShowArchived });
 
         // Fetch archived matches if switching to archived view and not yet loaded
-        if (newShowArchived && state.archivedMatches.length === 0) {
-            get().fetchArchivedMatches();
+        if (newShowArchived && state.loadedAt.archived === undefined) {
+            void get().fetchArchivedMatches();
         }
     },
 
@@ -360,7 +433,7 @@ clearMatches: () => {
     },
 
     // Pending (Your Turn) methods
-    fetchPendingQuestions: async () => {
+    fetchPendingQuestions: async (options = {}) => {
         const userId = useAuthStore.getState().user?.id;
         const coupleId = useAuthStore.getState().user?.couple_id;
 
@@ -369,22 +442,27 @@ clearMatches: () => {
             return;
         }
 
+        const myGeneration = get().generation;
         const state = get();
-        if (state.isLoadingPending) return;
-
-        set({ isLoadingPending: true });
+        if (inFlight.get('pending') === myGeneration) return;
+        if (!options.silent || state.loadedAt.pending === undefined) set({ isLoadingPending: true });
 
+        inFlight.set('pending', myGeneration);
         try {
             const { questions: pendingQuestions } = await apiClient.get<{questions:PendingQuestion[]}>("/v1/questions/pending?direction=partner");
-            set({ pendingQuestions, isLoadingPending: false });
+            if (get().generation !== myGeneration) return;
+            set((current) => ({ pendingQuestions, isLoadingPending: false, loadedAt: { ...current.loadedAt, pending: Date.now() } }));
         } catch (err) {
+            if (get().generation !== myGeneration) return;
             console.error("Error fetching pending questions:", err);
             set({ isLoadingPending: false });
+        } finally {
+            if (inFlight.get('pending') === myGeneration) inFlight.delete('pending');
         }
     },
 
     // Their Turn methods (user answered, partner hasn't yet)
-    fetchTheirTurnQuestions: async () => {
+    fetchTheirTurnQuestions: async (options = {}) => {
         const userId = useAuthStore.getState().user?.id;
         const coupleId = useAuthStore.getState().user?.couple_id;
 
@@ -393,35 +471,43 @@ clearMatches: () => {
             return;
         }
 
+        const myGeneration = get().generation;
         const state = get();
-        if (state.isLoadingTheirTurn) return;
-
-        set({ isLoadingTheirTurn: true });
+        if (inFlight.get('their_turn') === myGeneration) return;
+        if (!options.silent || state.loadedAt.their_turn === undefined) set({ isLoadingTheirTurn: true });
 
+        inFlight.set('their_turn', myGeneration);
         try {
             const { questions: theirTurnQuestions } = await apiClient.get<{questions:PendingQuestion[]}>("/v1/questions/pending?direction=mine");
-            set({ theirTurnQuestions, isLoadingTheirTurn: false });
+            if (get().generation !== myGeneration) return;
+            set((current) => ({ theirTurnQuestions, isLoadingTheirTurn: false, loadedAt: { ...current.loadedAt, their_turn: Date.now() } }));
         } catch (err) {
+            if (get().generation !== myGeneration) return;
             console.error("Error fetching their turn questions:", err);
             set({ isLoadingTheirTurn: false });
+        } finally {
+            if (inFlight.get('their_turn') === myGeneration) inFlight.delete('their_turn');
         }
     },
 
     setCurrentView: (view: MatchViewType) => {
-        const state = get();
-
         // Update showArchived for backwards compatibility
         const showArchived = view === 'archived';
         set({ currentView: view, showArchived });
 
-        // Fetch data for the selected view if not already loaded
-        if (view === 'archived' && state.archivedMatches.length === 0) {
-            get().fetchArchivedMatches();
-        } else if (view === 'pending' && state.pendingQuestions.length === 0) {
-            get().fetchPendingQuestions();
-        } else if (view === 'their_turn' && state.theirTurnQuestions.length === 0) {
-            get().fetchTheirTurnQuestions();
-        }
+        get().ensureViewLoaded(view);
+    },
+
+    /**
+     * Loads a view once. Emptiness is not evidence of never having loaded, so
+     * returning to a legitimately empty view costs no request at all.
+     */
+    ensureViewLoaded: (view = get().currentView) => {
+        if (get().loadedAt[view] !== undefined) return;
+        if (view === 'archived') void get().fetchArchivedMatches();
+        else if (view === 'pending') void get().fetchPendingQuestions();
+        else if (view === 'their_turn') void get().fetchTheirTurnQuestions();
+        else void get().fetchMatches(true);
     },
 
     // Nudge methods
@@ -436,10 +522,14 @@ clearMatches: () => {
             return { success: false, notificationSent: false };
         }
 
+        const myGeneration = state.generation;
         set({ isNudging: true });
 
         try {
             const data = await appDataApi.sendNudge();
+            // The cooldown is per-account. Recording the previous account's window
+            // would either silence the new account's nudge or clear a real cooldown.
+            if (get().generation !== myGeneration) return { success: false, notificationSent: false };
 
             // Success - update cooldown
             const cooldownUntil = data.next_nudge_available_at
@@ -453,6 +543,7 @@ clearMatches: () => {
                 notificationSent: data.notification_sent ?? false,
             };
         } catch (err) {
+            if (get().generation !== myGeneration) return { success: false, notificationSent: false };
             if (err instanceof ApiError && err.status === 429) {
                 const details = err.details as NudgeResponse | undefined;
                 const cooldownUntil = details?.next_nudge_available_at
@@ -471,8 +562,12 @@ clearMatches: () => {
         const userId = useAuthStore.getState().user?.id;
         if (!userId) return;
 
+        const myGeneration = get().generation;
         try {
             const profile = await appDataApi.nudgeStatus();
+            // Read for the previous account: neither its cooldown nor its absence
+            // says anything about whether this one may nudge.
+            if (get().generation !== myGeneration) return;
 
             if (!profile.last_nudge_sent_at) {
                 set({ nudgeCooldownUntil: null });

apps/mobile/src/store/messageStore.ts

@@ -19,7 +19,14 @@ interface MessageState {
     unreadCount: number;
     lastMessage: MessageWithMatch | null;
     activeMatchId: string | null; // Track which chat is currently open
+    /**
+     * Bumped by `clearMessages` on sign-out or a couple change, so a reply that
+     * outlives the account that asked for it cannot write into the next one's badge.
+     */
+    generation: number;
     fetchUnreadCount: () => Promise<void>;
+    /** Applies a count the sync summary already reported, without a second request. */
+    setUnreadCount: (total: number) => void;
     addMessage: (message: MessageWithMatch) => void;
     clearLastMessage: () => void;
     setActiveMatchId: (matchId: string | null) => void;
@@ -31,6 +38,7 @@ export const useMessageStore = create<MessageState>((set, get) => ({
     unreadCount: 0,
     lastMessage: null,
     activeMatchId: null,
+    generation: 0,
 
     fetchUnreadCount: async () => {
         const userId = useAuthStore.getState().user?.id;
@@ -39,10 +47,18 @@ export const useMessageStore = create<MessageState>((set, get) => ({
             return;
         }
 
+        const myGeneration = get().generation;
         const { total } = await chatApi.unread();
+        // This total counts one account's messages; after a clear it would show
+        // up as the next account's badge.
+        if (get().generation !== myGeneration) return;
         set({ unreadCount: total });
     },
 
+    setUnreadCount: (total) => {
+        set({ unreadCount: Math.max(0, total) });
+    },
+
     addMessage: (message) => {
         const userId = useAuthStore.getState().user?.id;
         const activeMatchId = get().activeMatchId;
@@ -68,18 +84,27 @@ export const useMessageStore = create<MessageState>((set, get) => ({
         const userId = useAuthStore.getState().user?.id;
         if (!userId) return;
 
+        const myGeneration = get().generation;
         const { updated: unreadInMatch } = await chatApi.markRead(matchId);
+        if (unreadInMatch <= 0) return;
 
-        // Refetch global unread count
-        await get().fetchUnreadCount();
+        // Those messages belonged to a couple that is no longer loaded, and the
+        // match they were in is not in the current list, so subtracting them now
+        // would take the old badge off the new account's.
+        if (get().generation !== myGeneration) return;
 
-        // Sync per-match unread count in matchStore
-        if (unreadInMatch > 0) {
+        // The server just told us exactly how many it cleared, so subtract instead
+        // of spending a request to re-read the total; the sync summary corrects
+        // any drift on its next pass.
+        set((state) => ({ unreadCount: Math.max(0, state.unreadCount - unreadInMatch) }));
         useMatchStore.getState().updateMatchUnreadCount(matchId, -unreadInMatch);
-        }
     },
 
     clearMessages: () => {
-        set({ unreadCount: 0, lastMessage: null, activeMatchId: null });
+        set((state) => ({
+            unreadCount: 0, lastMessage: null, activeMatchId: null,
+            // Invalidates any request already in flight for the account being left.
+            generation: state.generation + 1,
+        }));
     },
 }));

apps/mobile/src/store/packsStore.ts

@@ -4,6 +4,12 @@ import { Events } from "../lib/analytics";
 import type { QuestionPack, Category } from "@/types";
 import { useAuthStore } from "./authStore";
 
+// The catalog load fans out into three requests, so a second caller arriving mid-flight
+// must wait for the first rather than triple the cost. Keyed to the generation that
+// started the request: a stale generation's entry must not block the next account's
+// request for the same key, and its `finally` must not clear a newer generation's guard.
+const inFlight = new Map<string, number>();
+
 // Progress data for a pack
 export interface PackProgressData {
     totalQuestions: number;
@@ -16,10 +22,23 @@ interface PacksState {
     enabledPackIds: string[];
     packProgress: Map<string, PackProgressData>;
     isLoading: boolean;
+    /**
+     * When the catalog, enabled set and progress were last read together. Null means
+     * never — which is not the same as "empty", so a couple with no packs enabled
+     * stops refetching after the first load.
+     */
+    catalogLoadedAt: number | null;
+    /** Tracked separately because the swipe screen loads the enabled set on its own. */
+    enabledPacksLoadedAt: number | null;
+    /** Bumped on clear/sign-out so a response that outlives it cannot write into the next account's store. */
+    generation: number;
     fetchPacks: () => Promise<void>;
     fetchEnabledPacks: () => Promise<void>;
     fetchPackProgress: () => Promise<void>;
+    ensurePacksLoaded: () => Promise<void>;
     ensureEnabledPacksLoaded: () => Promise<void>;
+    /** Marks the cached catalog stale without spending a request; the next ensure reloads it. */
+    invalidatePacks: () => void;
     togglePack: (packId: string) => Promise<{ success: boolean; reason?: string }>;
     clearPacks: () => void;
     getPackProgress: (packId: string) => PackProgressData | undefined;
@@ -31,38 +50,61 @@ export const usePacksStore = create<PacksState>((set, get) => ({
     enabledPackIds: [],
     packProgress: new Map(),
     isLoading: false,
+    catalogLoadedAt: null,
+    enabledPacksLoadedAt: null,
+    generation: 0,
 
     fetchPacks: async () => {
+        const myGeneration = get().generation;
+        if (inFlight.get('catalog') === myGeneration) return;
+        inFlight.set('catalog', myGeneration);
         set({ isLoading: true });
         try {
             const catalog = await apiClient.get<{ categories: Category[]; packs: QuestionPack[] }>(
                 '/v1/packs?showAllIntensities=false',
             );
+            if (get().generation !== myGeneration) return;
             set({ packs: catalog.packs, categories: catalog.categories });
             await get().fetchEnabledPacks();
             await get().fetchPackProgress();
+            if (get().generation !== myGeneration) return;
+            set({ catalogLoadedAt: Date.now() });
         } finally {
-            set({ isLoading: false });
+            if (inFlight.get('catalog') === myGeneration) inFlight.delete('catalog');
+            if (get().generation === myGeneration) set({ isLoading: false });
         }
     },
 
+    ensurePacksLoaded: async () => {
+        if (get().catalogLoadedAt !== null) return;
+        await get().fetchPacks();
+    },
+
+    invalidatePacks: () => {
+        set({ catalogLoadedAt: null });
+    },
+
     fetchEnabledPacks: async () => {
         const coupleId = useAuthStore.getState().user?.couple_id;
+        const myGeneration = get().generation;
         if (!coupleId) {
-            set({ enabledPackIds: [] });
+            set({ enabledPackIds: [], enabledPacksLoadedAt: null });
             return;
         }
 
         const result = await apiClient.get<{ enabledPackIds: string[] }>("/v1/me/enabled-packs");
-        set({ enabledPackIds: result.enabledPackIds });
+        if (get().generation !== myGeneration) return;
+        set({ enabledPackIds: result.enabledPackIds, enabledPacksLoadedAt: Date.now() });
     },
 
     ensureEnabledPacksLoaded: async () => {
-        // Only fetch if not already loaded - lightweight check for swipe screen
+        // Only fetch if not already loaded - lightweight check for swipe screen.
+        // Keyed off the load marker, not the array: "no packs enabled" is a real
+        // answer and must not be retried on every visit.
         const coupleId = useAuthStore.getState().user?.couple_id;
         if (!coupleId) return;
 
-        if (get().enabledPackIds.length === 0) {
+        if (get().enabledPacksLoadedAt === null) {
             await get().fetchEnabledPacks();
         }
     },
@@ -73,6 +115,7 @@ export const usePacksStore = create<PacksState>((set, get) => ({
             return { success: false, reason: "no_couple" };
         }
 
+        const myGeneration = get().generation;
         const isEnabled = get().enabledPackIds.includes(packId);
         const newValue = !isEnabled;
 
@@ -88,9 +131,16 @@ export const usePacksStore = create<PacksState>((set, get) => ({
                 `/v1/me/enabled-packs/${packId}`,
                 { enabled: newValue },
             );
+            // These ids belong to the couple that asked; a clear while the request
+            // was open means they would land in a different couple's selection.
+            if (get().generation !== myGeneration) return { success: false, reason: "stale" };
             set({ enabledPackIds: result.enabledPackIds });
         } catch (error) {
             console.error("Error toggling pack:", error);
+            // The optimistic update this reverts was cleared along with everything
+            // else, so reverting now would only push a stale pack id into the next
+            // couple's list.
+            if (get().generation !== myGeneration) return { success: false, reason: "stale" };
             set({ enabledPackIds: isEnabled
                 ? [...new Set([...get().enabledPackIds, packId])]
                 : get().enabledPackIds.filter(id => id !== packId) });
@@ -108,6 +158,7 @@ export const usePacksStore = create<PacksState>((set, get) => ({
     },
 
     fetchPackProgress: async () => {
+        const myGeneration = get().generation;
         if (!useAuthStore.getState().user?.id) {
             set({ packProgress: new Map() });
             return;
@@ -115,6 +166,7 @@ export const usePacksStore = create<PacksState>((set, get) => ({
         const result = await apiClient.get<{ progress: Array<PackProgressData & { packId: string }> }>(
             "/v1/me/pack-progress",
         );
+        if (get().generation !== myGeneration) return;
         const progressMap = new Map<string, PackProgressData>();
         result.progress.forEach(({ packId, totalQuestions, answeredQuestions }) => {
             progressMap.set(packId, { totalQuestions, answeredQuestions });
@@ -128,6 +180,16 @@ export const usePacksStore = create<PacksState>((set, get) => ({
     },
 
     clearPacks: () => {
-        set({ enabledPackIds: [], packProgress: new Map() });
+        set((state) => ({
+            enabledPackIds: [],
+            packProgress: new Map(),
+            catalogLoadedAt: null,
+            enabledPacksLoadedAt: null,
+            // Invalidates any request already in flight for the signed-out user.
+            generation: state.generation + 1,
+        }));
+        // See matchStore.clearMatches: the previous user's in-flight catalog read
+        // must not block the next user's.
+        inFlight.clear();
     },
 }));

apps/mobile/src/store/responsesStore.ts

@@ -36,16 +36,33 @@ export type DateSortOrder = "newest" | "oldest";
 
 const BATCH_SIZE = 20;
 
+// Overlap protection independent of the presentational flags: a refresh over cached
+// rows raises `isRefreshing`, not `isLoading`, and still must not run twice. Keyed to
+// the generation that started the request: a stale generation's entry must not block
+// the next account's request, and its `finally` must not clear a newer generation's guard.
+const inFlight = new Map<string, number>();
+
 interface ResponsesState {
     responses: ResponseWithQuestion[];
+    /** First load only. A refresh over rows already on screen must not blank the list. */
     isLoading: boolean;
+    /** Refresh over cached rows; drives pull-to-refresh only. */
+    isRefreshing: boolean;
     isLoadingMore: boolean;
     groupBy: GroupByOption;
     dateSortOrder: DateSortOrder;
     hasMore: boolean;
     page: number;
     totalCount: number | null;
+    /** Null until the first successful read; an empty history is a loaded answer. */
+    loadedAt: number | null;
+    /** Bumped on clear/sign-out so a response that outlives it cannot write into the next account's store. */
+    generation: number;
     fetchResponses: (refresh?: boolean) => Promise<void>;
+    /** Loads the first page once; revisiting the screen reuses what is cached. */
+    ensureResponsesLoaded: () => Promise<void>;
+    /** Marks the cache stale without spending a request; the next ensure reloads it. */
+    invalidateResponses: () => void;
     updateResponse: (
         questionId: string,
         newAnswer: AnswerType,
@@ -61,12 +78,15 @@ interface ResponsesState {
 export const useResponsesStore = create<ResponsesState>((set, get) => ({
     responses: [],
     isLoading: false,
+    isRefreshing: false,
     isLoadingMore: false,
     groupBy: "date",
     dateSortOrder: "newest",
     hasMore: true,
     page: 0,
     totalCount: null,
+    loadedAt: null,
+    generation: 0,
 
     fetchResponses: async (refresh = false) => {
         const userId = useAuthStore.getState().user?.id;
@@ -74,25 +94,31 @@ export const useResponsesStore = create<ResponsesState>((set, get) => ({
 
         if (!userId || !coupleId) return;
 
+        const myGeneration = get().generation;
         const state = get();
-        if (state.isLoading || (state.isLoadingMore && !refresh)) return;
+        if (inFlight.get('responses') === myGeneration || (state.isLoadingMore && !refresh)) return;
 
+        // Nothing on screen yet is the only case that warrants a full-screen spinner;
+        // every other refresh leaves the cached rows in place until replacements land.
+        const initial = state.loadedAt === null;
         if (refresh) {
-            set({ isLoading: true, page: 0, hasMore: true });
+            set({ isLoading: initial, isRefreshing: !initial, page: 0, hasMore: true });
         } else {
             if (!state.hasMore) return;
             set({ isLoadingMore: true });
         }
 
+        inFlight.set('responses', myGeneration);
         try {
             const currentPage = refresh ? 0 : state.page;
             const result = await apiClient.get<{responses: ResponseWithQuestion[];totalCount:number}>(`/v1/me/responses?page=${currentPage}&limit=${BATCH_SIZE}`);
+            if (get().generation !== myGeneration) return;
             const responses = result.responses;
             const totalCount = result.totalCount;
 
             if (!responses || responses.length === 0) {
                 if (refresh) {
-                    set({ responses: [], totalCount: totalCount ?? 0, isLoading: false, hasMore: false });
+                    set({ responses: [], totalCount: totalCount ?? 0, isLoading: false, isRefreshing: false, hasMore: false, loadedAt: Date.now() });
                 } else {
                     set({ isLoadingMore: false, hasMore: false });
                 }
@@ -107,22 +133,37 @@ export const useResponsesStore = create<ResponsesState>((set, get) => ({
                     : [...state.responses, ...transformedResponses],
                 totalCount: refresh ? totalCount : state.totalCount,
                 isLoading: false,
+                isRefreshing: false,
                 isLoadingMore: false,
                 page: currentPage + 1,
-                hasMore: responses.length === BATCH_SIZE
+                hasMore: responses.length === BATCH_SIZE,
+                loadedAt: Date.now(),
             }));
         } catch (error) {
+            if (get().generation !== myGeneration) return;
             console.error("Error in fetchResponses:", error);
-            set({ isLoading: false, isLoadingMore: false });
+            set({ isLoading: false, isRefreshing: false, isLoadingMore: false });
+        } finally {
+            if (inFlight.get('responses') === myGeneration) inFlight.delete('responses');
         }
     },
 
+    ensureResponsesLoaded: async () => {
+        if (get().loadedAt !== null) return;
+        await get().fetchResponses(true);
+    },
+
+    invalidateResponses: () => {
+        set({ loadedAt: null });
+    },
+
     updateResponse: async (
         questionId: string,
         newAnswer: AnswerType,
         confirmDelete = false,
         responseData?: ResponseData | null
     ): Promise<UpdateResponseResult> => {
+        const myGeneration = get().generation;
         try {
             const result = await apiClient.patch<UpdateResponseResult>(`/v1/responses/${questionId}`, {
                 new_answer: newAnswer,
@@ -130,6 +171,13 @@ export const useResponsesStore = create<ResponsesState>((set, get) => ({
                 response_data: responseData,
             });
 
+            // Rows are keyed by a question id from the shared catalogue, so once the
+            // store has been cleared that same id can name a different account's
+            // answer. Hand the caller the server's result — it is true of whoever
+            // asked — but write nothing, and refresh no matches, for the account
+            // that is loaded now.
+            if (get().generation !== myGeneration) return result;
+
         // If update was successful (not just requiring confirmation), update local state
         if (result.success && !result.requires_confirmation) {
             // Update local response state
@@ -191,7 +239,15 @@ export const useResponsesStore = create<ResponsesState>((set, get) => ({
     },
 
     clearResponses: () => {
-        set({ responses: [], isLoading: false, groupBy: "date", dateSortOrder: "newest", page: 0, hasMore: true, isLoadingMore: false, totalCount: null });
+        set((state) => ({
+            responses: [], isLoading: false, isRefreshing: false, groupBy: "date", dateSortOrder: "newest",
+            page: 0, hasMore: true, isLoadingMore: false, totalCount: null, loadedAt: null,
+            // Invalidates any request already in flight for the signed-out user.
+            generation: state.generation + 1,
+        }));
+        // See matchStore.clearMatches: the previous user's in-flight page must not
+        // block the next user's.
+        inFlight.clear();
     },
 }));
 

apps/mobile/src/store/streakStore.ts

@@ -27,36 +27,84 @@ interface StreakState {
     streak: CoupleStreak | null;
     isLoading: boolean;
     error: string | null;
+    /**
+     * Null until the first successful read. A couple with no streak yet resolves to a
+     * null `streak`, which is a loaded answer rather than a reason to ask again.
+     */
+    loadedAt: number | null;
+    /** Bumped on clear/sign-out so a response that outlives it cannot write into the next account's store. */
+    generation: number;
 
     // Actions
     fetchStreak: () => Promise<void>;
+    /** Loads the streak once; later callers reuse the cached value. */
+    ensureStreakLoaded: () => Promise<void>;
+    /** Silent re-read of an already-loaded streak; leaves the cached value on screen if it fails. */
+    refreshStreak: () => Promise<void>;
     clearStreak: () => void;
 }
 
-export const useStreakStore = create<StreakState>((set) => ({
+// The streak is rendered by a badge, the home screen and the swipe screen, so
+// concurrent mounts must share one request rather than each issuing their own.
+// Tagged with the generation that started it: clearing/signing out bumps the
+// generation, so a stale response can no longer write into the next account's
+// store, and a stale `finally` cannot clear a newer generation's guard.
+let inFlight: { generation: number; promise: Promise<void> } | null = null;
+
+export const useStreakStore = create<StreakState>((set, get) => ({
     streak: null,
     isLoading: false,
     error: null,
+    loadedAt: null,
+    generation: 0,
 
     fetchStreak: async () => {
         const coupleId = useAuthStore.getState().user?.couple_id;
+        const myGeneration = get().generation;
         if (!coupleId) {
-            set({ streak: null, isLoading: false });
+            set({ streak: null, isLoading: false, loadedAt: null });
             return;
         }
 
+        if (inFlight && inFlight.generation === myGeneration) return inFlight.promise;
+
         set({ isLoading: true, error: null });
 
+        const promise = (async () => {
             try {
                 const { streak } = await apiClient.get<{streak: CoupleStreak | null}>("/v1/me/streak");
-            set({ streak, isLoading: false });
+                if (get().generation !== myGeneration) return;
+                set({ streak, isLoading: false, loadedAt: Date.now() });
             } catch (error) {
+                if (get().generation !== myGeneration) return;
                 console.error("Error fetching streak:", error);
                 set({ error: "Failed to load streak", isLoading: false });
+            } finally {
+                if (inFlight?.generation === myGeneration) inFlight = null;
             }
+        })();
+
+        inFlight = { generation: myGeneration, promise };
+        return promise;
+    },
+
+    ensureStreakLoaded: async () => {
+        if (get().loadedAt !== null) return;
+        await get().fetchStreak();
+    },
+
+    refreshStreak: async () => {
+        // Only silently refresh a streak the UI has actually loaded; an unopened
+        // screen has nothing cached to keep honest.
+        if (get().loadedAt === null) return;
+        await get().fetchStreak();
     },
 
     clearStreak: () => {
-        set({ streak: null, isLoading: false, error: null });
+        set((state) => ({
+            streak: null, isLoading: false, error: null, loadedAt: null,
+            // Invalidates any request already in flight for the signed-out user.
+            generation: state.generation + 1,
+        }));
     },
 }));

docs/agents/routing.md

@@ -1,21 +1,58 @@
 # Agent routing and effort
 
-Use one implementation agent by default. Add independent agents only when work is
-actually separable or a risk trigger requires independent judgment.
+The primary agent owns scope, acceptance criteria, task decomposition, and the
+final answer. Use one implementation agent when a bounded handoff will keep noisy
+execution out of the primary context. Do not pay the coordination cost for a
+trivial one-file edit. Add other agents only for separable work or a risk trigger.
 
-| Role | Default effort | Trigger | Do not use for |
-|---|---|---|---|
-| `repo-scout` | low | locate ownership, callers, contracts | editing or design decisions |
-| `implementation` | medium | bounded product or harness change | broad architecture review |
-| `test-writer` | medium | focused regression or missing contract test | rubber-stamping green output |
-| `verifier` | medium | independently drive changed behavior | editing implementation |
-| `database-reviewer` | medium | migrations, RLS, function/query boundaries | ordinary UI changes |
-| `security-reviewer` | high | auth, RLS, crypto, secrets, payments, destructive operations | every routine change |
-| `architecture-reviewer` | high | cross-cutting or hard-to-reverse decisions | local refactors |
+## Cost ladder
 
-Escalate effort only when uncertainty, blast radius, or irreversibility justifies
-it. “Proactively use” is not a trigger. Verification agents return evidence and a
-verdict; they do not make changes.
+Project Codex defaults live in `.codex/config.toml`; task profiles live in
+`.codex/agents/`. An explicit task handoff may raise or lower reasoning effort.
 
-Procedures belong in skills. Agents read the applicable skill and nearest
-`AGENTS.md`, then operate within the task's authorization.
+| Role | Codex model | Default effort | Trigger | Do not use for |
+|---|---|---:|---|---|
+| `repo_scout` | Luna | low | locate ownership, callers, contracts | editing or design decisions |
+| `implementation` | Terra | medium, overridable | bounded product or harness change | broad architecture review |
+| `test_writer` | Terra | medium | focused regression or missing contract test | rubber-stamping green output |
+| `verifier` | Terra | medium | independently drive implemented behavior | editing implementation |
+| `database_reviewer` | Terra | high | migrations, RLS, function/query boundaries | ordinary UI changes |
+| `security_reviewer` | Sol | high | auth, RLS, crypto, secrets, payments, destructive operations | every routine change |
+| `architecture_reviewer` | Sol | high | cross-cutting or hard-to-reverse decisions | local refactors |
+
+Claude profiles under `.claude/agents/` provide equivalent roles when Claude is
+explicitly requested. They are not part of the normal Codex routing path.
+
+## Implementation effort
+
+Keep `implementation` on Terra and choose effort from the task shape:
+
+- `low`: mechanical, fully specified, narrow change with an obvious check.
+- `medium`: normal feature or bug fix with a few files and known contracts.
+- `high`: ambiguous behavior, several interacting modules, concurrency, or
+  difficult debugging.
+- `xhigh`: exceptional Terra implementation where high effort has already proved
+  insufficient or the change has a large but non-security blast radius.
+
+Security and architecture risk are different jobs, not reasons to silently turn
+the implementation agent into a premium generalist. Add the matching read-only
+Sol reviewer and keep implementation on Terra unless the user explicitly asks for
+a different model.
+
+## Handoff contract
+
+Every delegated task includes the objective, owned files or surface, acceptance
+criteria, applicable `AGENTS.md` and skill, allowed side effects, required checks,
+and the evidence to return. The agent must report changed files, commands and
+results, assumptions, and blockers. The primary agent independently reviews the
+diff and decides whether acceptance has been met.
+
+Parallel agents are for independent read-heavy work or non-overlapping ownership.
+Avoid concurrent edits to the same files, shared database state, fixed local
+ports, or one simulator. Subagents consume additional tokens, so parallelism must
+buy meaningful time or independent judgment.
+
+Procedures belong in deterministic skills rather than agent prompts. Agents read
+the nearest `AGENTS.md` and the applicable repository skill, then operate only
+within the task's authorization. Verification agents return evidence and a
+verdict; they do not fix implementation.

docs/architecture/client-data-freshness.md

@@ -0,0 +1,195 @@
+# Client data freshness
+
+The mobile app talks to a request-per-read API with no realtime channel. This
+document is the contract for how it stays current without spending a request
+every time the user looks at something they have already loaded.
+
+## The invariant
+
+**Cached data is usable data.** Once a screen has loaded, switching away from it
+and back must cost zero requests and must never blank what is on screen. A
+refresh happens for a reason — the user pulled to refresh, a mutation invalidated
+the data, or a change marker moved — never merely because a screen regained
+focus.
+
+Three rules make that hold:
+
+- **Loaded-ness is recorded, not inferred.** Stores keep a marker
+  (`loadedAt`, `catalogLoadedAt`, `enabledPacksLoadedAt`) that is set on a
+  successful load and cleared on sign-out or explicit invalidation. Emptiness is
+  a legitimate answer, not evidence of never having loaded: keying off
+  `array.length === 0` makes every visit to an empty list pay for the same empty
+  response.
+- **Initial loading and refreshing are different states.** `isLoading` means
+  there is nothing to show yet and drives the full-screen loader. `isRefreshing`
+  drives pull-to-refresh only. A background refresh raises neither, so cached
+  rows stay on screen and in place until the replacement arrives.
+- **Invalidation is free.** A mutation that changes another screen's data marks
+  that cache stale (`invalidatePacks`, `invalidateResponses`) instead of
+  refetching it. Whichever screen the user opens next reloads once; screens they
+  do not open stay quiet.
+
+Overlap protection lives in a module-scoped `inFlight` set rather than in the
+loading flags, because a silent refresh raises no flag and still must not issue a
+second request. The set is cleared alongside the store on sign-out, so a
+signed-out user's in-flight request cannot suppress the next user's.
+
+## Recurring work
+
+`usePolling` (`apps/mobile/src/hooks/usePolling.ts`) owns every recurring read.
+It schedules the next run after the previous one settles rather than on a fixed
+interval, so a slow response delays the next request instead of queueing one
+behind it, and it provides three properties no hand-rolled interval in this app
+had:
+
+- it stops while the app is backgrounded or `inactive`, and catches up
+  immediately on return;
+- it never runs two passes concurrently;
+- it backs off exponentially — to `maxIntervalMs`, eight intervals by default —
+  while the API is failing.
+
+Callers gate it further with `enabled`, which carries screen focus, a loaded id,
+or a paired couple. Screens pass focus in as a prop rather than having the hook
+read navigation state, so hooks stay renderable without a navigator.
+
+| Poller | Interval | Runs while |
+|---|---|---|
+| Couple sync (`useCoupleSync`) | 15s | signed in, app foregrounded |
+| Chat messages | 2s | chat screen focused |
+| Dares | 5s | dares screen focused |
+| Live draw | 750ms | canvas focused |
+
+Live draw keeps the sub-second cadence a shared canvas needs, but only for the
+seconds someone is actually looking at it.
+
+## `GET /v1/me/sync`
+
+One small query summarising everything the app used to discover by re-reading
+five endpoints. The client compares it against the previous summary and refreshes
+only the domains whose markers moved — and only those already loaded, so a view
+nobody has opened is never fetched in the background.
+
+| Field | Moves when |
+|---|---|
+| `server_time` | every call |
+| `couple_id`, `profile_updated_at` | the user's own profile or couple membership changed |
+| `partner_id`, `partner_updated_at` | the partner's profile changed |
+| `match_count`, `new_match_count`, `latest_match_at` | matches were created, seen, or archived |
+| `pending_yours`, `pending_theirs` | either side answered a question the other is waiting on |
+| `unread_total` | chat unread count for this user changed |
+| `enabled_packs_fingerprint` | the couple's enabled pack set changed |
+| `match_state_fingerprint` | a visible match's type or response summary changed in place |
+| `match_unread_fingerprint` | unread moved between matches, with or without a change to the total |
+| `streak_updated_at` | the couple's streak row changed |
+
+`unread_total` is applied directly to the badge, so keeping it current costs
+nothing beyond this request. The first poll after sign-in only establishes the
+baseline: every screen loads its own data on mount, and refreshing it again would
+undo the saving.
+
+`enabled_packs_fingerprint` is an `md5` digest of the enabled pack ids rather
+than a timestamp, because `couple_packs` carries no `updated_at` and equal and
+opposite toggles would otherwise be invisible. Zero enabled packs is the stable
+digest of the empty string, not `null`.
+
+The two match digests exist for the same reason in a different shape: the counts
+and `latest_match_at` all hold steady when a partner edits an existing match in
+place, and `unread_total` holds steady when unread merely moves between matches —
+which still reorders an unread-first list.
+
+Every field is derived for the calling identity's own couple. The summary reveals
+nothing about any other couple, and reveals no partner content — only that
+something moved.
+
+## Chat deltas
+
+`GET /v1/matches/:id/messages` takes two optional parameters:
+
+- `since` — an ISO 8601 timestamp with offset. Returns only rows whose visible
+  state moved since then: created, delivered, read, deleted, media viewed, or a
+  video whose `media_expires_at` fell inside the window. Messages are not
+  editable, so there is no edit to report. A malformed value is rejected with
+  `400 invalid_since` rather than silently treated as a full read.
+- `typing=true` — folds the partner's typing state into the same response, so a
+  focused chat makes one request per pass instead of two.
+
+The response is a `MessagesPage`:
+
+| Field | Meaning |
+|---|---|
+| `messages` | rows to merge by id, newest first |
+| `removed_ids` | rows the client must drop (deleted, or deleted-for-self) |
+| `server_time` | cursor for the next `since` |
+| `complete` | true when this is a full snapshot rather than a delta |
+| `typing` | present only when `typing=true` was requested |
+
+`server_time` is deliberately set two seconds behind `now()` so a row committed
+during the request cannot fall between two cursors. The overlap re-returns a
+handful of already-known rows, which is harmless because the client merges by id.
+
+`media_expired` is derived in the query — `media_expired or media_expires_at <=
+now()` — rather than read from the stored column, which nothing ever writes. That
+is the rule the media endpoint already applies when it refuses an expired object,
+so a client is no longer handed a video it will not be allowed to fetch. Expiry is
+also the one visible change no row write announces, which is why the delta
+compares the deadline against the poll window rather than looking for a timestamp
+that moved; the row is emitted in the single window its deadline falls into.
+
+`moderation_status`, `flag_reason` and `category` are returned in full but are
+**not** covered by `since`: the classifier and the admin tool rewrite them without
+advancing any timestamp, so a delta cannot see them move. No client renders them
+today, so nothing user-visible goes stale — but a client that started rendering
+them would need a cursor for them, which means a new column on `messages`.
+
+Deltas do not change access control, ordering, media fields, or deletion
+semantics: a delta returns exactly the rows a full read would have returned for
+that window, and a caller outside the couple still gets `match_not_found`.
+
+The client marks the conversation read only when a response actually contains an
+unread partner message, and `POST .../read` returns the number of rows it
+cleared, so the badge is adjusted by subtraction rather than by re-reading the
+total.
+
+## Match pagination
+
+`GET /v1/matches` returns `{ matches, totalCount, hasMore }`.
+
+`totalCount` is a `number` on page 0 and **`null` on every later page**: the
+count is a full scan of the couple's matches and nothing in the UI needs it more
+than once per refresh. Clients keep the value from the refresh that started the
+sequence.
+
+`hasMore` comes from reading `limit + 1` rows and reporting whether the extra one
+existed, so an exactly-full final page reports `false` correctly. Unread counts
+are aggregated once in a CTE rather than by a correlated subquery per row.
+Ordering (unread first, then newest) and couple isolation are unchanged.
+
+Pagination itself is still page-number/`OFFSET`-based, not cursor-based. This
+pass removed the repeated `count(*)` and the per-row unread subquery — the two
+costs that scaled with the couple's history — but paging deep into a large
+history still pays an `OFFSET` scan. Cursor pagination would remove that too;
+it has not been implemented.
+
+## `GET /v1/me` is idempotent
+
+Bootstrapping a profile reads first and writes only what actually differs. An
+unchanged read leaves both `updated_at` and `auth_synced_at` alone, so a client
+polling `/v1/me` no longer produces a write per call. First use still creates
+the profile from the auth identity's name, avatar and email. On every later
+call only a changed **email** writes through, syncing the one field the auth
+provider is authoritative for; the product's display name and avatar are not
+touched, so a locally-edited name or avatar is never overwritten by
+potentially stale auth metadata.
+
+## One database pool
+
+The API process creates a single `pg` pool and passes it to every repository, so
+the process holds one bounded set of server connections rather than a
+default-sized pool per domain. Shutdown ends that pool once. Repositories still
+accept a connection string in tests, in which case they own and end the pool they
+created — see `resolvePool` / `closeResolvedPool` in `apps/api/src/db/pool.ts`.
+
+Bounds come from `DATABASE_POOL_MAX` (default 10),
+`DATABASE_POOL_IDLE_TIMEOUT_MS` (30000) and
+`DATABASE_POOL_CONNECTION_TIMEOUT_MS` (10000). They are process-wide; keep the
+total across running instances inside the database's own connection limit.

docs/dares-loop.md

@@ -121,9 +121,15 @@ rejected.
 ## Mobile
 
 Reached from the home screen's `DaresTile`, which badges pending incoming dares. The
-screen has Active / Send / History tabs, polls on a 5s interval (there is no realtime
-channel), and opens the paywall both proactively and in reaction to a `402` — a client
-whose entitlement went stale still lands on the paywall rather than an error.
+screen has Active / Send / History tabs and opens the paywall both proactively and in
+reaction to a `402` — a client whose entitlement went stale still lands on the paywall
+rather than an error.
+
+There is no realtime channel, so the screen polls on a 5s interval — but only while it is
+focused and the app is foregrounded, and each pass reads the active list alone. History,
+the catalogue and the stats are re-read only when the active set's ids or statuses
+actually changed, or on an explicit refresh or a mutation. See
+[Client data freshness](architecture/client-data-freshness.md).
 
 ## Tests
 

docs/index.md

@@ -6,6 +6,7 @@ historical notes. Agents should load only the section relevant to their task.
 ## Maintained system documentation
 
 - [System architecture](architecture/system.md)
+- [Client data freshness](architecture/client-data-freshness.md)
 - [Local full-stack development](development/local-stack.md)
 - [Testing strategy](testing/strategy.md)
 - [Database migration safety](operations/database-migrations.md)

scripts/lint-harness.mjs

@@ -23,6 +23,10 @@ function fail(file, message, fix) {
   errors.push(`${path.relative(root, file)}: ${message}\n  Fix: ${fix}`);
 }
 
+function tomlString(source, key) {
+  return source.match(new RegExp(`^${key}\\s*=\\s*"([^"]+)"\\s*$`, 'm'))?.[1];
+}
+
 const allFiles = await walk(root);
 for (const file of allFiles) {
   if (path.basename(file) === 'agents.md') {
@@ -37,6 +41,57 @@ for (const file of allFiles) {
 
 if (!scoped) {
   const packageJson = JSON.parse(await readFile(path.join(root, 'package.json'), 'utf8'));
+  const codexConfigFile = path.join(root, '.codex', 'config.toml');
+  const codexConfig = await readFile(codexConfigFile, 'utf8');
+  if (!/^\[agents\]$/m.test(codexConfig) || !/^enabled\s*=\s*true$/m.test(codexConfig)) {
+    fail(codexConfigFile, 'project subagent routing is not enabled', 'restore the [agents] table with enabled = true');
+  }
+  if (tomlString(codexConfig, 'default_subagent_model') !== 'gpt-5.6-terra') {
+    fail(codexConfigFile, 'ordinary subagents no longer default to the cost-balanced model', 'set default_subagent_model = "gpt-5.6-terra"');
+  }
+  if (tomlString(codexConfig, 'default_subagent_reasoning_effort') !== 'medium') {
+    fail(codexConfigFile, 'ordinary subagent effort is no longer the balanced default', 'set default_subagent_reasoning_effort = "medium"');
+  }
+  const maxThreads = Number(codexConfig.match(/^max_concurrent_threads_per_session\s*=\s*(\d+)$/m)?.[1]);
+  if (!Number.isInteger(maxThreads) || maxThreads < 1 || maxThreads > 3) {
+    fail(codexConfigFile, 'subagent concurrency is missing or exceeds the repository cost cap', 'set max_concurrent_threads_per_session between 1 and 3');
+  }
+
+  const agentContracts = {
+    'repo-scout.toml': { name: 'repo_scout', model: 'gpt-5.6-luna', effort: 'low', readOnly: true },
+    'implementation.toml': { name: 'implementation', model: 'gpt-5.6-terra', effort: null, flexibleEffort: true },
+    'test-writer.toml': { name: 'test_writer', model: 'gpt-5.6-terra', effort: 'medium' },
+    'verifier.toml': { name: 'verifier', model: 'gpt-5.6-terra', effort: 'medium' },
+    'database-reviewer.toml': { name: 'database_reviewer', model: 'gpt-5.6-terra', effort: 'high', readOnly: true },
+    'security-reviewer.toml': { name: 'security_reviewer', model: 'gpt-5.6-sol', effort: 'high', readOnly: true },
+    'architecture-reviewer.toml': { name: 'architecture_reviewer', model: 'gpt-5.6-sol', effort: 'high', readOnly: true },
+  };
+  for (const [filename, contract] of Object.entries(agentContracts)) {
+    const agentFile = path.join(root, '.codex', 'agents', filename);
+    if (!(await exists(agentFile))) {
+      fail(agentFile, 'required task-agent profile is missing', `restore .codex/agents/${filename}`);
+      continue;
+    }
+    const source = await readFile(agentFile, 'utf8');
+    if (tomlString(source, 'name') !== contract.name || tomlString(source, 'model') !== contract.model) {
+      fail(agentFile, 'task-agent identity or cost tier drifted', `set name = "${contract.name}" and model = "${contract.model}"`);
+    }
+    const effort = tomlString(source, 'model_reasoning_effort');
+    if (contract.flexibleEffort ? effort !== undefined : effort !== contract.effort) {
+      fail(
+        agentFile,
+        contract.flexibleEffort ? 'implementation reasoning is pinned and cannot flex by task complexity' : 'task-agent reasoning effort drifted',
+        contract.flexibleEffort ? 'omit model_reasoning_effort so the handoff or project default controls it' : `set model_reasoning_effort = "${contract.effort}"`,
+      );
+    }
+    if (contract.readOnly && tomlString(source, 'sandbox_mode') !== 'read-only') {
+      fail(agentFile, 'review-only agent can mutate the workspace', 'set sandbox_mode = "read-only"');
+    }
+    if (!/^description\s*=\s*".+"$/m.test(source) || !/developer_instructions\s*=\s*"""[\s\S]*\S[\s\S]*"""/m.test(source)) {
+      fail(agentFile, 'custom agent is missing its required description or instructions', 'restore non-empty description and developer_instructions fields');
+    }
+  }
+
   const mobilePackageFile = path.join(root, 'apps', 'mobile', 'package.json');
   const mobilePackageJson = JSON.parse(await readFile(mobilePackageFile, 'utf8'));
   const releaseBuildScripts = Object.entries(mobilePackageJson.scripts ?? {})