diff --git a/packages/storage/package.json b/packages/storage/package.json
index 3b233ec..36d1661 100644
--- a/packages/storage/package.json
+++ b/packages/storage/package.json
@@ -16,6 +16,7 @@
     "test": "vitest run --passWithNoTests"
   },
   "dependencies": {
+    "@mosaic/db": "workspace:^",
     "@mosaic/types": "workspace:*"
   },
   "devDependencies": {
diff --git a/packages/storage/src/adapters/postgres.ts b/packages/storage/src/adapters/postgres.ts
new file mode 100644
index 0000000..f6c69a5
--- /dev/null
+++ b/packages/storage/src/adapters/postgres.ts
@@ -0,0 +1,252 @@
+import {
+  createDb,
+  runMigrations,
+  eq,
+  and,
+  asc,
+  desc,
+  sql,
+  type Db,
+  type DbHandle,
+} from '@mosaic/db';
+import * as schema from '@mosaic/db';
+import type { StorageAdapter, StorageConfig } from '../types.js';
+
+/* eslint-disable @typescript-eslint/no-explicit-any */
+
+/**
+ * Maps collection name → Drizzle table object.
+ * Typed as `any` because the generic StorageAdapter interface erases table
+ * types — all runtime values are still strongly-typed Drizzle table objects.
+ */
+const TABLE_MAP: Record<string, any> = {
+  users: schema.users,
+  sessions: schema.sessions,
+  accounts: schema.accounts,
+  verifications: schema.verifications,
+  teams: schema.teams,
+  team_members: schema.teamMembers,
+  projects: schema.projects,
+  missions: schema.missions,
+  tasks: schema.tasks,
+  mission_tasks: schema.missionTasks,
+  events: schema.events,
+  agents: schema.agents,
+  tickets: schema.tickets,
+  appreciations: schema.appreciations,
+  conversations: schema.conversations,
+  messages: schema.messages,
+  preferences: schema.preferences,
+  insights: schema.insights,
+  agent_logs: schema.agentLogs,
+  skills: schema.skills,
+  routing_rules: schema.routingRules,
+  provider_credentials: schema.providerCredentials,
+  summarization_jobs: schema.summarizationJobs,
+};
+
+function getTable(collection: string): any {
+  const table = TABLE_MAP[collection];
+  if (!table) throw new Error(`Unknown collection: ${collection}`);
+  return table;
+}
+
+function buildWhereClause(table: any, filter?: Record<string, unknown>) {
+  if (!filter || Object.keys(filter).length === 0) return undefined;
+  const conditions = Object.entries(filter).map(([key, value]) => {
+    const column = table[key];
+    if (!column) throw new Error(`Unknown column "${key}" on table`);
+    return eq(column, value);
+  });
+  return conditions.length === 1 ? conditions[0]! : and(...conditions);
+}
+
+export class PostgresAdapter implements StorageAdapter {
+  readonly name = 'postgres';
+  private handle: DbHandle;
+  private db: Db;
+  private url: string;
+
+  constructor(config: Extract<StorageConfig, { type: 'postgres' }>) {
+    this.url = config.url;
+    this.handle = createDb(config.url);
+    this.db = this.handle.db;
+  }
+
+  async create<T extends Record<string, unknown>>(
+    collection: string,
+    data: T,
+  ): Promise<T & { id: string }> {
+    const table = getTable(collection);
+    const [row] = await (this.db as any).insert(table).values(data).returning();
+    return row as T & { id: string };
+  }
+
+  async read<T extends Record<string, unknown>>(collection: string, id: string): Promise<T | null> {
+    const table = getTable(collection);
+    const [row] = await (this.db as any).select().from(table).where(eq(table.id, id));
+    return (row as T) ?? null;
+  }
+
+  async update(collection: string, id: string, data: Record<string, unknown>): Promise<boolean> {
+    const table = getTable(collection);
+    const result = await (this.db as any)
+      .update(table)
+      .set(data)
+      .where(eq(table.id, id))
+      .returning();
+    return result.length > 0;
+  }
+
+  async delete(collection: string, id: string): Promise<boolean> {
+    const table = getTable(collection);
+    const result = await (this.db as any).delete(table).where(eq(table.id, id)).returning();
+    return result.length > 0;
+  }
+
+  async find<T extends Record<string, unknown>>(
+    collection: string,
+    filter?: Record<string, unknown>,
+    opts?: { limit?: number; offset?: number; orderBy?: string; order?: 'asc' | 'desc' },
+  ): Promise<T[]> {
+    const table = getTable(collection);
+    let query = (this.db as any).select().from(table);
+    const where = buildWhereClause(table, filter);
+    if (where) query = query.where(where);
+    if (opts?.orderBy) {
+      const col = table[opts.orderBy];
+      if (col) {
+        query = query.orderBy(opts.order === 'desc' ? desc(col) : asc(col));
+      }
+    }
+    if (opts?.limit) query = query.limit(opts.limit);
+    if (opts?.offset) query = query.offset(opts.offset);
+    return (await query) as T[];
+  }
+
+  async findOne<T extends Record<string, unknown>>(
+    collection: string,
+    filter: Record<string, unknown>,
+  ): Promise<T | null> {
+    const results = await this.find<T>(collection, filter, { limit: 1 });
+    return results[0] ?? null;
+  }
+
+  async count(collection: string, filter?: Record<string, unknown>): Promise<number> {
+    const table = getTable(collection);
+    let query = (this.db as any).select({ count: sql<number>`count(*)::int` }).from(table);
+    const where = buildWhereClause(table, filter);
+    if (where) query = query.where(where);
+    const [row] = await query;
+    return (row as any)?.count ?? 0;
+  }
+
+  async transaction<T>(fn: (tx: StorageAdapter) => Promise<T>): Promise<T> {
+    return (this.db as any).transaction(async (drizzleTx: any) => {
+      const txAdapter = new PostgresTxAdapter(drizzleTx, this.url);
+      return fn(txAdapter);
+    });
+  }
+
+  async migrate(): Promise<void> {
+    await runMigrations(this.url);
+  }
+
+  async close(): Promise<void> {
+    await this.handle.close();
+  }
+}
+
+/**
+ * Thin transaction wrapper — delegates to the Drizzle transaction object
+ * instead of the top-level db handle.
+ */
+class PostgresTxAdapter implements StorageAdapter {
+  readonly name = 'postgres';
+  private tx: any;
+  private url: string;
+
+  constructor(tx: any, url: string) {
+    this.tx = tx;
+    this.url = url;
+  }
+
+  async create<T extends Record<string, unknown>>(
+    collection: string,
+    data: T,
+  ): Promise<T & { id: string }> {
+    const table = getTable(collection);
+    const [row] = await this.tx.insert(table).values(data).returning();
+    return row as T & { id: string };
+  }
+
+  async read<T extends Record<string, unknown>>(collection: string, id: string): Promise<T | null> {
+    const table = getTable(collection);
+    const [row] = await this.tx.select().from(table).where(eq(table.id, id));
+    return (row as T) ?? null;
+  }
+
+  async update(collection: string, id: string, data: Record<string, unknown>): Promise<boolean> {
+    const table = getTable(collection);
+    const result = await this.tx.update(table).set(data).where(eq(table.id, id)).returning();
+    return result.length > 0;
+  }
+
+  async delete(collection: string, id: string): Promise<boolean> {
+    const table = getTable(collection);
+    const result = await this.tx.delete(table).where(eq(table.id, id)).returning();
+    return result.length > 0;
+  }
+
+  async find<T extends Record<string, unknown>>(
+    collection: string,
+    filter?: Record<string, unknown>,
+    opts?: { limit?: number; offset?: number; orderBy?: string; order?: 'asc' | 'desc' },
+  ): Promise<T[]> {
+    const table = getTable(collection);
+    let query = this.tx.select().from(table);
+    const where = buildWhereClause(table, filter);
+    if (where) query = query.where(where);
+    if (opts?.orderBy) {
+      const col = table[opts.orderBy];
+      if (col) {
+        query = query.orderBy(opts.order === 'desc' ? desc(col) : asc(col));
+      }
+    }
+    if (opts?.limit) query = query.limit(opts.limit);
+    if (opts?.offset) query = query.offset(opts.offset);
+    return (await query) as T[];
+  }
+
+  async findOne<T extends Record<string, unknown>>(
+    collection: string,
+    filter: Record<string, unknown>,
+  ): Promise<T | null> {
+    const results = await this.find<T>(collection, filter, { limit: 1 });
+    return results[0] ?? null;
+  }
+
+  async count(collection: string, filter?: Record<string, unknown>): Promise<number> {
+    const table = getTable(collection);
+    let query = this.tx.select({ count: sql<number>`count(*)::int` }).from(table);
+    const where = buildWhereClause(table, filter);
+    if (where) query = query.where(where);
+    const [row] = await query;
+    return (row as any)?.count ?? 0;
+  }
+
+  async transaction<T>(fn: (tx: StorageAdapter) => Promise<T>): Promise<T> {
+    return this.tx.transaction(async (nestedTx: any) => {
+      const nested = new PostgresTxAdapter(nestedTx, this.url);
+      return fn(nested);
+    });
+  }
+
+  async migrate(): Promise<void> {
+    await runMigrations(this.url);
+  }
+
+  async close(): Promise<void> {
+    // No-op inside a transaction
+  }
+}
diff --git a/packages/storage/src/index.ts b/packages/storage/src/index.ts
index 52f6448..6974b07 100644
--- a/packages/storage/src/index.ts
+++ b/packages/storage/src/index.ts
@@ -1,2 +1,11 @@
 export type { StorageAdapter, StorageConfig } from './types.js';
 export { createStorageAdapter, registerStorageAdapter } from './factory.js';
+export { PostgresAdapter } from './adapters/postgres.js';
+
+import { registerStorageAdapter } from './factory.js';
+import { PostgresAdapter } from './adapters/postgres.js';
+import type { StorageConfig } from './types.js';
+
+registerStorageAdapter('postgres', (config: StorageConfig) => {
+  return new PostgresAdapter(config as Extract<StorageConfig, { type: 'postgres' }>);
+});
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index bf7d0b9..74c8296 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -570,6 +570,22 @@ importers:
         specifier: ^2.0.0
         version: 2.1.9(@types/node@24.12.0)(jsdom@29.0.0(@noble/hashes@2.0.1))(lightningcss@1.31.1)
 
+  packages/storage:
+    dependencies:
+      '@mosaic/db':
+        specifier: workspace:^
+        version: link:../db
+      '@mosaic/types':
+        specifier: workspace:*
+        version: link:../types
+    devDependencies:
+      typescript:
+        specifier: ^5.8.0
+        version: 5.9.3
+      vitest:
+        specifier: ^2.0.0
+        version: 2.1.9(@types/node@24.12.0)(jsdom@29.0.0(@noble/hashes@2.0.1))(lightningcss@1.31.1)
+
   packages/types:
     dependencies:
       class-transformer: