feat(P4-001): @mosaic/memory — preference + insight stores

Add memory tables to DB schema (preferences, insights with pgvector
embedding column, agent_logs, skills, summarization_jobs). Implement
PreferencesRepo (CRUD + upsert) and InsightsRepo (CRUD + semantic
search + relevance decay). Define VectorStore and EmbeddingProvider
interfaces for future provider abstraction. Wire MemoryModule into
gateway with REST endpoints at /api/memory/*.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/gateway/package.json

@@ -18,6 +18,7 @@
     "@mosaic/brain": "workspace:^",
     "@mosaic/coord": "workspace:^",
     "@mosaic/db": "workspace:^",
+    "@mosaic/memory": "workspace:^",
     "@mosaic/types": "workspace:^",
     "@nestjs/common": "^11.0.0",
     "@nestjs/core": "^11.0.0",

apps/gateway/src/app.module.ts

@@ -10,6 +10,7 @@ import { ProjectsModule } from './projects/projects.module.js';
 import { MissionsModule } from './missions/missions.module.js';
 import { TasksModule } from './tasks/tasks.module.js';
 import { CoordModule } from './coord/coord.module.js';
+import { MemoryModule } from './memory/memory.module.js';
 
 @Module({
   imports: [
@@ -23,6 +24,7 @@ import { CoordModule } from './coord/coord.module.js';
     MissionsModule,
     TasksModule,
     CoordModule,
+    MemoryModule,
   ],
   controllers: [HealthController],
 })

apps/gateway/src/memory/memory.controller.ts

@@ -0,0 +1,108 @@
+import {
+  Body,
+  Controller,
+  Delete,
+  Get,
+  HttpCode,
+  HttpStatus,
+  Inject,
+  NotFoundException,
+  Param,
+  Post,
+  Query,
+  UseGuards,
+} from '@nestjs/common';
+import type { Memory } from '@mosaic/memory';
+import { MEMORY } from './memory.tokens.js';
+import { AuthGuard } from '../auth/auth.guard.js';
+import type { UpsertPreferenceDto, CreateInsightDto, SearchMemoryDto } from './memory.dto.js';
+
+@Controller('api/memory')
+@UseGuards(AuthGuard)
+export class MemoryController {
+  constructor(@Inject(MEMORY) private readonly memory: Memory) {}
+
+  // ─── Preferences ────────────────────────────────────────────────────
+
+  @Get('preferences')
+  async listPreferences(@Query('userId') userId: string, @Query('category') category?: string) {
+    if (category) {
+      return this.memory.preferences.findByUserAndCategory(
+        userId,
+        category as Parameters<typeof this.memory.preferences.findByUserAndCategory>[1],
+      );
+    }
+    return this.memory.preferences.findByUser(userId);
+  }
+
+  @Get('preferences/:key')
+  async getPreference(@Query('userId') userId: string, @Param('key') key: string) {
+    const pref = await this.memory.preferences.findByUserAndKey(userId, key);
+    if (!pref) throw new NotFoundException('Preference not found');
+    return pref;
+  }
+
+  @Post('preferences')
+  async upsertPreference(@Query('userId') userId: string, @Body() dto: UpsertPreferenceDto) {
+    return this.memory.preferences.upsert({
+      userId,
+      key: dto.key,
+      value: dto.value,
+      category: dto.category,
+      source: dto.source,
+    });
+  }
+
+  @Delete('preferences/:key')
+  @HttpCode(HttpStatus.NO_CONTENT)
+  async removePreference(@Query('userId') userId: string, @Param('key') key: string) {
+    const deleted = await this.memory.preferences.remove(userId, key);
+    if (!deleted) throw new NotFoundException('Preference not found');
+  }
+
+  // ─── Insights ───────────────────────────────────────────────────────
+
+  @Get('insights')
+  async listInsights(@Query('userId') userId: string, @Query('limit') limit?: string) {
+    return this.memory.insights.findByUser(userId, limit ? Number(limit) : undefined);
+  }
+
+  @Get('insights/:id')
+  async getInsight(@Param('id') id: string) {
+    const insight = await this.memory.insights.findById(id);
+    if (!insight) throw new NotFoundException('Insight not found');
+    return insight;
+  }
+
+  @Post('insights')
+  async createInsight(@Query('userId') userId: string, @Body() dto: CreateInsightDto) {
+    return this.memory.insights.create({
+      userId,
+      content: dto.content,
+      source: dto.source,
+      category: dto.category,
+      metadata: dto.metadata,
+    });
+  }
+
+  @Delete('insights/:id')
+  @HttpCode(HttpStatus.NO_CONTENT)
+  async removeInsight(@Param('id') id: string) {
+    const deleted = await this.memory.insights.remove(id);
+    if (!deleted) throw new NotFoundException('Insight not found');
+  }
+
+  // ─── Search ─────────────────────────────────────────────────────────
+
+  @Post('search')
+  async searchMemory(@Query('userId') userId: string, @Body() dto: SearchMemoryDto) {
+    // Search requires an embedding provider to be configured.
+    // For now, return empty results if no embedding is available.
+    // P4-002 will implement the full embedding + search pipeline.
+    return {
+      query: dto.query,
+      results: [],
+      message: 'Semantic search requires embedding provider (P4-002)',
+    };
+  }
+}

apps/gateway/src/memory/memory.dto.ts

@@ -0,0 +1,19 @@
+export interface UpsertPreferenceDto {
+  key: string;
+  value: unknown;
+  category?: 'communication' | 'coding' | 'workflow' | 'appearance' | 'general';
+  source?: string;
+}
+
+export interface CreateInsightDto {
+  content: string;
+  source?: 'agent' | 'user' | 'summarization' | 'system';
+  category?: 'decision' | 'learning' | 'preference' | 'fact' | 'pattern' | 'general';
+  metadata?: Record<string, unknown>;
+}
+
+export interface SearchMemoryDto {
+  query: string;
+  limit?: number;
+  maxDistance?: number;
+}

apps/gateway/src/memory/memory.module.ts

@@ -0,0 +1,20 @@
+import { Global, Module } from '@nestjs/common';
+import { createMemory, type Memory } from '@mosaic/memory';
+import type { Db } from '@mosaic/db';
+import { DB } from '../database/database.module.js';
+import { MEMORY } from './memory.tokens.js';
+import { MemoryController } from './memory.controller.js';
+
+@Global()
+@Module({
+  providers: [
+    {
+      provide: MEMORY,
+      useFactory: (db: Db): Memory => createMemory(db),
+      inject: [DB],
+    },
+  ],
+  controllers: [MemoryController],
+  exports: [MEMORY],
+})
+export class MemoryModule {}

apps/gateway/src/memory/memory.tokens.ts

@@ -0,0 +1 @@
+export const MEMORY = 'MEMORY';

packages/db/src/index.ts

@@ -1,4 +1,18 @@
 export { createDb, type Db, type DbHandle } from './client.js';
 export { runMigrations } from './migrate.js';
 export * from './schema.js';
-export { eq, and, or, desc, asc, sql, inArray, isNull, isNotNull } from 'drizzle-orm';
+export {
+  eq,
+  and,
+  or,
+  desc,
+  asc,
+  sql,
+  inArray,
+  isNull,
+  isNotNull,
+  gt,
+  lt,
+  gte,
+  lte,
+} from 'drizzle-orm';

packages/db/src/schema.ts

@@ -3,7 +3,18 @@
  * drizzle-kit reads this file directly (avoids CJS/ESM extension issues).
  */
 
-import { pgTable, text, timestamp, boolean, uuid, jsonb, index } from 'drizzle-orm/pg-core';
+import {
+  pgTable,
+  text,
+  timestamp,
+  boolean,
+  uuid,
+  jsonb,
+  index,
+  real,
+  integer,
+  customType,
+} from 'drizzle-orm/pg-core';
 
 // ─── Auth (BetterAuth-compatible) ────────────────────────────────────────────
 
@@ -211,3 +222,152 @@ export const messages = pgTable(
   },
   (t) => [index('messages_conversation_id_idx').on(t.conversationId)],
 );
+
+// ─── pgvector custom type ───────────────────────────────────────────────────
+
+const vector = customType<{ data: number[]; driverParam: string; config: { dimensions: number } }>({
+  dataType(config) {
+    return `vector(${config?.dimensions ?? 1536})`;
+  },
+  fromDriver(value: unknown): number[] {
+    const str = value as string;
+    return str
+      .slice(1, -1)
+      .split(',')
+      .map((v) => Number(v));
+  },
+  toDriver(value: number[]): string {
+    return `[${value.join(',')}]`;
+  },
+});
+
+// ─── Memory ─────────────────────────────────────────────────────────────────
+
+export const preferences = pgTable(
+  'preferences',
+  {
+    id: uuid('id').primaryKey().defaultRandom(),
+    userId: text('user_id')
+      .notNull()
+      .references(() => users.id, { onDelete: 'cascade' }),
+    key: text('key').notNull(),
+    value: jsonb('value').notNull(),
+    category: text('category', {
+      enum: ['communication', 'coding', 'workflow', 'appearance', 'general'],
+    })
+      .notNull()
+      .default('general'),
+    source: text('source'),
+    createdAt: timestamp('created_at', { withTimezone: true }).notNull().defaultNow(),
+    updatedAt: timestamp('updated_at', { withTimezone: true }).notNull().defaultNow(),
+  },
+  (t) => [
+    index('preferences_user_id_idx').on(t.userId),
+    index('preferences_user_key_idx').on(t.userId, t.key),
+  ],
+);
+
+export const insights = pgTable(
+  'insights',
+  {
+    id: uuid('id').primaryKey().defaultRandom(),
+    userId: text('user_id')
+      .notNull()
+      .references(() => users.id, { onDelete: 'cascade' }),
+    content: text('content').notNull(),
+    embedding: vector('embedding', { dimensions: 1536 }),
+    source: text('source', {
+      enum: ['agent', 'user', 'summarization', 'system'],
+    })
+      .notNull()
+      .default('agent'),
+    category: text('category', {
+      enum: ['decision', 'learning', 'preference', 'fact', 'pattern', 'general'],
+    })
+      .notNull()
+      .default('general'),
+    relevanceScore: real('relevance_score').notNull().default(1.0),
+    metadata: jsonb('metadata'),
+    createdAt: timestamp('created_at', { withTimezone: true }).notNull().defaultNow(),
+    updatedAt: timestamp('updated_at', { withTimezone: true }).notNull().defaultNow(),
+    decayedAt: timestamp('decayed_at', { withTimezone: true }),
+  },
+  (t) => [
+    index('insights_user_id_idx').on(t.userId),
+    index('insights_category_idx').on(t.category),
+    index('insights_relevance_idx').on(t.relevanceScore),
+  ],
+);
+
+// ─── Agent Logs ─────────────────────────────────────────────────────────────
+
+export const agentLogs = pgTable(
+  'agent_logs',
+  {
+    id: uuid('id').primaryKey().defaultRandom(),
+    sessionId: text('session_id').notNull(),
+    userId: text('user_id').references(() => users.id, { onDelete: 'set null' }),
+    level: text('level', { enum: ['debug', 'info', 'warn', 'error'] })
+      .notNull()
+      .default('info'),
+    category: text('category', {
+      enum: ['decision', 'tool_use', 'learning', 'error', 'general'],
+    })
+      .notNull()
+      .default('general'),
+    content: text('content').notNull(),
+    metadata: jsonb('metadata'),
+    tier: text('tier', { enum: ['hot', 'warm', 'cold'] })
+      .notNull()
+      .default('hot'),
+    createdAt: timestamp('created_at', { withTimezone: true }).notNull().defaultNow(),
+    summarizedAt: timestamp('summarized_at', { withTimezone: true }),
+    archivedAt: timestamp('archived_at', { withTimezone: true }),
+  },
+  (t) => [
+    index('agent_logs_session_id_idx').on(t.sessionId),
+    index('agent_logs_user_id_idx').on(t.userId),
+    index('agent_logs_tier_idx').on(t.tier),
+    index('agent_logs_created_at_idx').on(t.createdAt),
+  ],
+);
+
+// ─── Skills ─────────────────────────────────────────────────────────────────
+
+export const skills = pgTable(
+  'skills',
+  {
+    id: uuid('id').primaryKey().defaultRandom(),
+    name: text('name').notNull().unique(),
+    description: text('description'),
+    version: text('version'),
+    source: text('source', { enum: ['builtin', 'community', 'custom'] })
+      .notNull()
+      .default('custom'),
+    config: jsonb('config'),
+    enabled: boolean('enabled').notNull().default(true),
+    installedBy: text('installed_by').references(() => users.id, { onDelete: 'set null' }),
+    createdAt: timestamp('created_at', { withTimezone: true }).notNull().defaultNow(),
+    updatedAt: timestamp('updated_at', { withTimezone: true }).notNull().defaultNow(),
+  },
+  (t) => [index('skills_enabled_idx').on(t.enabled)],
+);
+
+// ─── Summarization Jobs ─────────────────────────────────────────────────────
+
+export const summarizationJobs = pgTable(
+  'summarization_jobs',
+  {
+    id: uuid('id').primaryKey().defaultRandom(),
+    status: text('status', { enum: ['pending', 'running', 'completed', 'failed'] })
+      .notNull()
+      .default('pending'),
+    logsProcessed: integer('logs_processed').notNull().default(0),
+    insightsCreated: integer('insights_created').notNull().default(0),
+    errorMessage: text('error_message'),
+    startedAt: timestamp('started_at', { withTimezone: true }),
+    completedAt: timestamp('completed_at', { withTimezone: true }),
+    createdAt: timestamp('created_at', { withTimezone: true }).notNull().defaultNow(),
+  },
+  (t) => [index('summarization_jobs_status_idx').on(t.status)],
+);

packages/memory/package.json

@@ -1,6 +1,7 @@
 {
   "name": "@mosaic/memory",
   "version": "0.0.0",
+  "type": "module",
   "main": "dist/index.js",
   "types": "dist/index.d.ts",
   "exports": {
@@ -16,7 +17,9 @@
     "test": "vitest run --passWithNoTests"
   },
   "dependencies": {
-    "@mosaic/types": "workspace:*"
+    "@mosaic/db": "workspace:*",
+    "@mosaic/types": "workspace:*",
+    "drizzle-orm": "^0.45.1"
   },
   "devDependencies": {
     "typescript": "^5.8.0",

packages/memory/src/index.ts

@@ -1 +1,15 @@
-export const VERSION = '0.0.0';
+export { createMemory, type Memory } from './memory.js';
+export {
+  createPreferencesRepo,
+  type PreferencesRepo,
+  type Preference,
+  type NewPreference,
+} from './preferences.js';
+export {
+  createInsightsRepo,
+  type InsightsRepo,
+  type Insight,
+  type NewInsight,
+  type SearchResult,
+} from './insights.js';
+export type { VectorStore, VectorSearchResult, EmbeddingProvider } from './vector-store.js';

packages/memory/src/insights.ts

@@ -0,0 +1,89 @@
+import { eq, and, desc, sql, lt, type Db, insights } from '@mosaic/db';
+
+export type Insight = typeof insights.$inferSelect;
+export type NewInsight = typeof insights.$inferInsert;
+
+export interface SearchResult {
+  insight: Insight;
+  distance: number;
+}
+
+export function createInsightsRepo(db: Db) {
+  return {
+    async findByUser(userId: string, limit = 50): Promise<Insight[]> {
+      return db
+        .select()
+        .from(insights)
+        .where(eq(insights.userId, userId))
+        .orderBy(desc(insights.createdAt))
+        .limit(limit);
+    },
+
+    async findById(id: string): Promise<Insight | undefined> {
+      const rows = await db.select().from(insights).where(eq(insights.id, id));
+      return rows[0];
+    },
+
+    async create(data: NewInsight): Promise<Insight> {
+      const rows = await db.insert(insights).values(data).returning();
+      return rows[0]!;
+    },
+
+    async update(id: string, data: Partial<NewInsight>): Promise<Insight | undefined> {
+      const rows = await db
+        .update(insights)
+        .set({ ...data, updatedAt: new Date() })
+        .where(eq(insights.id, id))
+        .returning();
+      return rows[0];
+    },
+
+    async remove(id: string): Promise<boolean> {
+      const rows = await db.delete(insights).where(eq(insights.id, id)).returning();
+      return rows.length > 0;
+    },
+
+    /**
+     * Semantic search using pgvector cosine distance.
+     * Requires the vector extension and an embedding for the query.
+     */
+    async searchByEmbedding(
+      userId: string,
+      queryEmbedding: number[],
+      limit = 10,
+      maxDistance = 0.8,
+    ): Promise<SearchResult[]> {
+      const embeddingStr = `[${queryEmbedding.join(',')}]`;
+      const rows = await db.execute(sql`
+        SELECT *,
+               (embedding <=> ${embeddingStr}::vector) AS distance
+        FROM insights
+        WHERE user_id = ${userId}
+          AND embedding IS NOT NULL
+          AND (embedding <=> ${embeddingStr}::vector) < ${maxDistance}
+        ORDER BY distance ASC
+        LIMIT ${limit}
+      `);
+
+      return rows as unknown as SearchResult[];
+    },
+
+    /**
+     * Decay relevance scores for old insights that haven't been accessed recently.
+     */
+    async decayOldInsights(olderThan: Date, decayFactor = 0.95): Promise<number> {
+      const result = await db
+        .update(insights)
+        .set({
+          relevanceScore: sql`${insights.relevanceScore} * ${decayFactor}`,
+          decayedAt: new Date(),
+          updatedAt: new Date(),
+        })
+        .where(and(lt(insights.updatedAt, olderThan), sql`${insights.relevanceScore} > 0.1`))
+        .returning();
+      return result.length;
+    },
+  };
+}
+
+export type InsightsRepo = ReturnType<typeof createInsightsRepo>;

packages/memory/src/memory.ts

@@ -0,0 +1,15 @@
+import type { Db } from '@mosaic/db';
+import { createPreferencesRepo, type PreferencesRepo } from './preferences.js';
+import { createInsightsRepo, type InsightsRepo } from './insights.js';
+
+export interface Memory {
+  preferences: PreferencesRepo;
+  insights: InsightsRepo;
+}
+
+export function createMemory(db: Db): Memory {
+  return {
+    preferences: createPreferencesRepo(db),
+    insights: createInsightsRepo(db),
+  };
+}

packages/memory/src/preferences.ts

@@ -0,0 +1,59 @@
+import { eq, and, type Db, preferences } from '@mosaic/db';
+
+export type Preference = typeof preferences.$inferSelect;
+export type NewPreference = typeof preferences.$inferInsert;
+
+export function createPreferencesRepo(db: Db) {
+  return {
+    async findByUser(userId: string): Promise<Preference[]> {
+      return db.select().from(preferences).where(eq(preferences.userId, userId));
+    },
+
+    async findByUserAndKey(userId: string, key: string): Promise<Preference | undefined> {
+      const rows = await db
+        .select()
+        .from(preferences)
+        .where(and(eq(preferences.userId, userId), eq(preferences.key, key)));
+      return rows[0];
+    },
+
+    async findByUserAndCategory(
+      userId: string,
+      category: Preference['category'],
+    ): Promise<Preference[]> {
+      return db
+        .select()
+        .from(preferences)
+        .where(and(eq(preferences.userId, userId), eq(preferences.category, category)));
+    },
+
+    async upsert(data: NewPreference): Promise<Preference> {
+      const existing = await db
+        .select()
+        .from(preferences)
+        .where(and(eq(preferences.userId, data.userId), eq(preferences.key, data.key)));
+
+      if (existing[0]) {
+        const rows = await db
+          .update(preferences)
+          .set({ value: data.value, category: data.category, updatedAt: new Date() })
+          .where(eq(preferences.id, existing[0].id))
+          .returning();
+        return rows[0]!;
+      }
+
+      const rows = await db.insert(preferences).values(data).returning();
+      return rows[0]!;
+    },
+
+    async remove(userId: string, key: string): Promise<boolean> {
+      const rows = await db
+        .delete(preferences)
+        .where(and(eq(preferences.userId, userId), eq(preferences.key, key)))
+        .returning();
+      return rows.length > 0;
+    },
+  };
+}
+
+export type PreferencesRepo = ReturnType<typeof createPreferencesRepo>;

packages/memory/src/vector-store.ts

@@ -0,0 +1,39 @@
+/**
+ * VectorStore interface — abstraction over pgvector that allows future
+ * swap to Qdrant, Pinecone, etc.
+ */
+export interface VectorStore {
+  /** Store an embedding with an associated document ID. */
+  store(documentId: string, embedding: number[], metadata?: Record<string, unknown>): Promise<void>;
+
+  /** Search for similar embeddings, returning document IDs and distances. */
+  search(
+    queryEmbedding: number[],
+    limit?: number,
+    filter?: Record<string, unknown>,
+  ): Promise<VectorSearchResult[]>;
+
+  /** Delete an embedding by document ID. */
+  remove(documentId: string): Promise<void>;
+}
+
+export interface VectorSearchResult {
+  documentId: string;
+  distance: number;
+  metadata?: Record<string, unknown>;
+}
+
+/**
+ * EmbeddingProvider interface — generates embeddings from text.
+ * Implemented by the gateway using the configured LLM provider.
+ */
+export interface EmbeddingProvider {
+  /** Generate an embedding vector for the given text. */
+  embed(text: string): Promise<number[]>;
+
+  /** Generate embeddings for multiple texts in batch. */
+  embedBatch(texts: string[]): Promise<number[][]>;
+
+  /** The dimensionality of the embeddings this provider generates. */
+  dimensions: number;
+}

pnpm-lock.yaml

@@ -59,6 +59,9 @@ importers:
       '@mosaic/db':
         specifier: workspace:^
         version: link:../../packages/db
+      '@mosaic/memory':
+        specifier: workspace:^
+        version: link:../../packages/memory
       '@mosaic/types':
         specifier: workspace:^
         version: link:../../packages/types
@@ -331,9 +334,15 @@ importers:
 
   packages/memory:
     dependencies:
+      '@mosaic/db':
+        specifier: workspace:*
+        version: link:../db
       '@mosaic/types':
         specifier: workspace:*
         version: link:../types
+      drizzle-orm:
+        specifier: ^0.45.1
+        version: 0.45.1(@opentelemetry/api@1.9.0)(@types/pg@8.15.6)(kysely@0.28.11)(postgres@3.4.8)
     devDependencies:
       typescript:
         specifier: ^5.8.0