diff --git a/README.md b/README.md
index 8f5b8ca..7c5c5d0 100644
--- a/README.md
+++ b/README.md
@@ -3,7 +3,7 @@
 This repository now contains a two-container stack:
 
 - `frontend/` – a Next.js 14 web UI that reimplements the original single-page experience
-- `backend/` – an Express API with Prisma + SQLite that provides authentication, base/category/defense CRUD, statistics, and image uploads
+- `backend/` – an Express API with Prisma + PostgreSQL that provides authentication, base/category/defense CRUD, statistics, and image uploads
 
 Everything runs via Docker so you can deploy directly to Dokploy (or any Docker-based host).
 
@@ -12,7 +12,9 @@ Everything runs via Docker so you can deploy directly to Dokploy (or any Docker-
 The Dokploy-oriented compose files assume production domains. For a local smoke test you can temporarily override the variables at runtime:
 
 ```bash
-JWT_SECRET=dev-secret docker compose -f docker-compose.backend.yml up --build -d
+JWT_SECRET=dev-secret \
+DATABASE_URL="postgresql://basenoter:basenoter@localhost:5432/basenoter?schema=public" \
+docker compose -f docker-compose.backend.yml up --build -d
 NEXT_PUBLIC_BACKEND_URL=http://localhost:4000 docker compose -f docker-compose.frontend.yml up --build -d
 ```
 
@@ -25,11 +27,12 @@ Default environment variables ship in `backend/.env.example`. Copy it (e.g. to `
 
 **Persistent data**
 
-The compose file provisions two named volumes:
+The compose file provisions a single named volume:
 
-- `backend-data` – stores the Prisma SQLite database (`/app/dev.db`)
 - `backend-uploads` – stores uploaded base layout images (`/app/uploads`)
 
+Because the API now targets PostgreSQL, you must supply an external database connection string via the `DATABASE_URL` environment variable (e.g., through Dokploy secrets pointing at your managed Postgres instance).
+
 ## Backend details (`backend/`)
 
 - Express 4 REST API
@@ -43,7 +46,7 @@ Environment variables (see `.env.example`):
 
 | Variable           | Purpose                                      |
 |-------------------|----------------------------------------------|
-| `DATABASE_URL`     | Prisma connection string (default SQLite)     |
+| `DATABASE_URL`     | Prisma connection string (PostgreSQL)         |
 | `JWT_SECRET`       | Secret for signing JWT auth cookies          |
 | `FRONTEND_ORIGIN`  | CORS allowlist (e.g. `http://localhost:3100`) |
 | `COOKIE_SECURE`    | Set to `true` when serving over HTTPS        |
@@ -69,7 +72,7 @@ Steps:
 2. In Dokploy create two Compose apps, each pointing to the respective file above.
 3. Provide secrets for `JWT_SECRET` (backend) and any overrides you need; TLS-terminated installs should leave `COOKIE_SECURE` as `true`.
 4. Dokploy's Traefik proxy will use the embedded labels to route the domains listed earlier. Adjust `entrypoints`/`certresolver` if your installation uses different names.
-5. Configure persistent volumes for `/app/dev.db` and `/app/uploads`, or switch Prisma to an external database before deployment.
+5. Configure the `DATABASE_URL` secret to point at your managed Postgres instance and mount the `backend-uploads` volume, or adjust the compose file to include a local Postgres service for testing.
 
 ## Development without Docker
 
@@ -86,6 +89,14 @@ npm run dev
 
 Set `NEXT_PUBLIC_BACKEND_URL=http://localhost:4100` for the frontend.
 
+For the backend, provide a PostgreSQL connection string such as:
+
+```
+DATABASE_URL="postgresql://basenoter:basenoter@localhost:5432/basenoter?schema=public"
+```
+
+When developing locally you can point this URL at any Postgres instance you manage (Docker Desktop, remote cloud database, etc.).
+
 ## Image handling
 
 Uploaded base images are saved to `/app/uploads` inside the backend container and served at `http://<backend>/uploads/<filename>`. You can switch to an object store by swapping the Multer storage in `src/server.js`.
diff --git a/backend/prisma/schema.prisma b/backend/prisma/schema.prisma
index f853145..9376b7e 100644
--- a/backend/prisma/schema.prisma
+++ b/backend/prisma/schema.prisma
@@ -3,7 +3,7 @@ generator client {
 }
 
 datasource db {
-  provider = "sqlite"
+  provider = "postgresql"
   url      = env("DATABASE_URL")
 }
 
diff --git a/docker-compose.backend.yml b/docker-compose.backend.yml
index 0e9b389..4292396 100644
--- a/docker-compose.backend.yml
+++ b/docker-compose.backend.yml
@@ -3,12 +3,11 @@ services:
     build:
       context: ./backend
     environment:
-      DATABASE_URL: file:./dev.db
+      DATABASE_URL: ${DATABASE_URL:?Set DATABASE_URL in Dokploy secrets}
       JWT_SECRET: ${JWT_SECRET:?Set JWT_SECRET in Dokploy secrets}
       FRONTEND_ORIGIN: https://basetracker.lona-development.org
       COOKIE_SECURE: "true"
     volumes:
-      - backend-data:/app/dev.db
       - backend-uploads:/app/uploads
     ports:
       - "4000:4000"
@@ -22,5 +21,4 @@ services:
       - traefik.http.services.backend.loadbalancer.server.port=4000
 
 volumes:
-  backend-data:
   backend-uploads: