diff --git a/DOCKER.md b/DOCKER.md
index d0623c1..0863d95 100644
--- a/DOCKER.md
+++ b/DOCKER.md
@@ -6,11 +6,12 @@ This guide covers everything you need to run any part of the Call of Code platfo
 
 ## Overview
 
-The repository ships with **four Docker Compose configurations**:
+The repository ships with **five Docker Compose configurations**:
 
 | File | Purpose | Services |
 |------|---------|----------|
 | `docker-compose.yml` | **API-only** dev (standalone) | `coc-api` |
+| `docker/docker-compose.yml` | **All platforms** master stack | all 6 services |
 | `docker/coc-member/docker-compose.yml` | Full **COC Member** stack | `coc-api` + `server` + `web` |
 | `docker/coc-admin/docker-compose.yml` | Full **COC Admin** stack | `coc-api` + `server` + `web` |
 | `docker/callofcode.in/docker-compose.yml` | Full **callofcode.in** website stack | `coc-api` + `frontend` |
@@ -76,6 +77,35 @@ cp docker/callofcode.in/.env.local.frontend.example docker/callofcode.in/.env.lo
 
 ## Running the Stacks
 
+### All platforms together (master stack)
+
+Use this when you need all three platforms running simultaneously (e.g. testing cross-platform API behaviour or running the full suite locally):
+
+```bash
+# From the repo root — watch mode recommended
+docker compose -f docker/docker-compose.yml up --watch
+
+# Or standard mode
+docker compose -f docker/docker-compose.yml up --build
+```
+
+All six services share a single `coc-network` bridge and a single `coc-api` instance:
+
+| Service | Container | Host port | Override env var |
+|---------|-----------|-----------|------------------|
+| `coc-api` | `3000` | **3000** | `COC_API_PORT` |
+| `callofcode-frontend` | `3001` | **3001** | `CALLOFCODE_PORT` |
+| `coc-admin-server` | `8000` | **8001** | `COC_ADMIN_BACKEND_PORT` |
+| `coc-admin-web` | `5173` | **5174** | `COC_ADMIN_FRONTEND_PORT` |
+| `coc-member-server` | `8000` | **8002** | `COC_MEMBER_BACKEND_PORT` |
+| `coc-member-web` | `5173` | **5175** | `COC_MEMBER_FRONTEND_PORT` |
+
+> **Port remapping**: because `coc-admin` and `coc-member` both internally bind `8000` and `5173`, the master stack remaps them to unique host ports to avoid conflicts. Internal service-to-service communication (`API_URL=http://coc-api:3000`) still uses the original container ports.
+
+> **Env files required**: make sure all six env files exist before starting (see [Environment Setup](#environment-setup) above).
+
+---
+
 ### API-only (standalone development)
 
 Use this when you're only working on the `coc-api` itself:
@@ -217,10 +247,14 @@ The dev compose files use `target: builder` so that devDependencies and the Pris
 The `dockerfile:` path in compose is relative to the `context`, not the compose file. Our configs set `context: ../..` (repo root) so `dockerfile: Dockerfile` resolves correctly.
 
 **Port already in use**
-Set a custom port via the `PORT` env variable before running:
+For the individual stacks, set a custom port via the `PORT` env variable:
 ```bash
 PORT=3001 docker compose up
 ```
+For the master stack, override the specific service port:
+```bash
+COC_API_PORT=3010 COC_ADMIN_BACKEND_PORT=8010 docker compose -f docker/docker-compose.yml up
+```
 
 **Prisma migration errors on startup**
 The `coc-api` container runs `prisma migrate deploy` on every start. If the DB is unreachable, the container will exit. Verify your `DATABASE_URL` and `DIRECT_URL` in `.env.local`.
diff --git a/README.md b/README.md
index e8f198e..adf8a04 100644
--- a/README.md
+++ b/README.md
@@ -69,7 +69,8 @@ COC-API/
 │   ├── SiteContent.test.ts
 │   └── imageUtils.test.ts
 │
-├── docker/                  # Platform-specific Docker Compose stacks
+├── docker/                  # Docker Compose stacks
+│   ├── docker-compose.yml   # ★ Master stack — all platforms together
 │   ├── coc-member/          # Full COC Member platform stack
 │   │   ├── docker-compose.yml
 │   │   ├── .env.local.backend.example
@@ -145,9 +146,12 @@ bun install
 
 ### 4. Local development (Docker)
 
-The project ships **four Docker Compose stacks**. Choose the one you need:
+The project ships **five Docker Compose stacks**. Choose the one you need:
 
 ```bash
+# ★ All platforms at once (recommended for full-stack development)
+docker compose -f docker/docker-compose.yml up --watch
+
 # API only (for coc-api development)
 docker compose up --build
 
diff --git a/docker/docker-compose.yml b/docker/docker-compose.yml
new file mode 100644
index 0000000..449172e
--- /dev/null
+++ b/docker/docker-compose.yml
@@ -0,0 +1,173 @@
+# =============================================================================
+# Master Docker Compose — All Platforms
+# Runs coc-api + all three frontends/backends together on a single network.
+#
+# Usage:
+#   docker compose -f docker/docker-compose.yml up --watch
+#
+# Port map:
+#   3000  → coc-api            (shared API)
+#   3001  → callofcode.in      (frontend)
+#   8001  → coc-admin backend
+#   5174  → coc-admin frontend
+#   8002  → coc-member backend
+#   5175  → coc-member frontend
+# =============================================================================
+
+name: coc-all
+
+services:
+
+  coc-api:
+    image: coc-api
+    build:
+      context: ..
+      dockerfile: Dockerfile
+      target: builder        # builder stage has devDeps + bun --watch
+    restart: unless-stopped
+    ports:
+      - "${COC_API_PORT:-3000}:3000"
+    env_file:
+      - ../.env.local        # Local dev env vars (Supabase connection strings, etc.)
+    environment:
+      NODE_ENV: development
+    volumes:
+      - ../:/app
+      - /app/node_modules
+      - /app/node_modules/.prisma
+    command: >
+      sh -c "bunx prisma generate &&
+             bunx prisma migrate deploy &&
+             bun --watch src/server.ts"
+    develop:
+      watch:
+        - path: ../src
+          action: sync
+          target: /app/src
+        - path: ../package.json
+          action: rebuild
+        - path: ../bun.lock
+          action: rebuild
+        - path: ../prisma
+          action: rebuild
+    healthcheck:
+      test: ["CMD", "wget", "--quiet", "--tries=1", "--spider", "http://localhost:3000/health"]
+      interval: 30s
+      timeout: 10s
+      retries: 3
+      start_period: 15s
+    networks:
+      - coc-network
+
+  # callofcode.in — main website frontend
+
+  callofcode-frontend:
+    image: callofcode07/callofcode:latest
+    pull_policy: missing
+    restart: unless-stopped
+    ports:
+      - "${CALLOFCODE_PORT:-3001}:3001"
+    env_file:
+      - callofcode.in/.env.local.frontend
+    environment:
+      - NODE_ENV=development
+      - API_BASE_URL=http://coc-api:3000
+    depends_on:
+      coc-api:
+        condition: service_healthy
+    networks:
+      - coc-network
+    command: ["npm", "run", "dev"]
+
+  # coc-admin — admin backend
+
+  coc-admin-server:
+    image: callofcode07/coc-admin-backend:latest
+    pull_policy: missing
+    restart: unless-stopped
+    ports:
+      - "${COC_ADMIN_BACKEND_PORT:-8001}:8000"   # remapped to 8001 to avoid conflict
+    env_file:
+      - coc-admin/.env.local.backend
+    environment:
+      - PORT=8000
+      - API_URL=http://coc-api:3000
+      - ALLOWED_ORIGINS=http://localhost:${COC_ADMIN_FRONTEND_PORT:-5174}
+    depends_on:
+      coc-api:
+        condition: service_healthy
+    healthcheck:
+      test: ["CMD", "wget", "-qO-", "http://localhost:8000/health"]
+      interval: 30s
+      timeout: 3s
+      retries: 3
+      start_period: 10s
+    networks:
+      - coc-network
+
+  # coc-admin — admin frontend
+  coc-admin-web:
+    image: callofcode07/coc-admin-frontend:latest
+    pull_policy: missing
+    restart: unless-stopped
+    ports:
+      - "${COC_ADMIN_FRONTEND_PORT:-5174}:5173"  # remapped to 5174 to avoid conflict
+    env_file:
+      - coc-admin/.env.local.frontend
+    environment:
+      - VITE_API_URL=http://localhost:8001
+    depends_on:
+      coc-admin-server:
+        condition: service_healthy
+    networks:
+      - coc-network
+
+  # ---------------------------------------------------------------------------
+  # coc-member — member backend
+  # ---------------------------------------------------------------------------
+  coc-member-server:
+    image: callofcode07/coc-member-backend:latest
+    pull_policy: missing
+    restart: unless-stopped
+    ports:
+      - "${COC_MEMBER_BACKEND_PORT:-8002}:8000"  # remapped to 8002 to avoid conflict
+    env_file:
+      - coc-member/.env.local.backend
+    environment:
+      - PORT=8000
+      - API_URL=http://coc-api:3000
+      - ALLOWED_ORIGINS=http://localhost:${COC_MEMBER_FRONTEND_PORT:-5175}
+    depends_on:
+      coc-api:
+        condition: service_healthy
+    healthcheck:
+      test: ["CMD", "wget", "-qO-", "http://localhost:8000/health"]
+      interval: 30s
+      timeout: 3s
+      retries: 3
+      start_period: 10s
+    networks:
+      - coc-network
+
+  # ---------------------------------------------------------------------------
+  # coc-member — member frontend
+  # ---------------------------------------------------------------------------
+  coc-member-web:
+    image: callofcode07/coc-member-frontend:latest
+    pull_policy: missing
+    restart: unless-stopped
+    ports:
+      - "${COC_MEMBER_FRONTEND_PORT:-5175}:5173"  # remapped to 5175 to avoid conflict
+    env_file:
+      - coc-member/.env.local.frontend
+    environment:
+      - VITE_API_URL=http://localhost:8002
+    depends_on:
+      coc-member-server:
+        condition: service_healthy
+    networks:
+      - coc-network
+
+networks:
+  coc-network:
+    driver: bridge