Dockerize Anything

Production-grade containers, not "FROM node, COPY . ., npm start".

1. Detect

• Language, version (.nvmrc, engines, .python-version, go.mod, rust-toolchain), and package manager plus lockfile.
• Build command, start command, port, and the env vars the app reads (search for process.env, os.environ, os.Getenv...).
• Services it depends on (Postgres, Redis, Mongo...) from config and dependencies.
• Whether a Dockerfile already exists. If so, improve it instead of replacing it.

2. Dockerfile rules

• Multi-stage: a deps → build → runtime chain. Only runtime artifacts end up in the final stage.
• Pinned, slim base images: node:<ver>-alpine or -slim, python:<ver>-slim, and gcr.io/distroless/static for Go and Rust static binaries.
• Layer caching: copy the lockfiles first, install dependencies, then copy the source.
• Install production dependencies only (npm ci --omit=dev, pip install --no-cache-dir, CGO_ENABLED=0).
• Non-root user, EXPOSE <port>, HEALTHCHECK when there's an HTTP endpoint, and exec-form CMD.
• No secrets in the image. Pass them as runtime env or BuildKit secrets.

3. Also generate

• .dockerignore: .git, node_modules, .venv, build output, .env*, logs, tests, and docs if they aren't needed.
• docker-compose.yml: the app plus the detected services, with named volumes, healthcheck, depends_on: condition: service_healthy and env_file: .env.
• .env.example entries for each variable the app requires.

4. Verify (if Docker is available)

docker build -t <app>:local .
docker images <app>:local --format '{{.Size}}'
docker compose up -d && docker compose ps && docker compose logs --tail=50 app

Fix any failures, then report the final image size and how to run it. Run docker compose down when you're done.