Docker Development Env

1. Create a dev Dockerfile - use a multi-stage Dockerfile with a dev target that includes dev dependencies and debugging tools.
2. Set up docker-compose for development - define all services (app, database, cache) with dev-friendly settings.
3. Configure bind mounts - mount source code from the host into the container for live editing.
4. Enable hot reload - configure the framework's file watcher to work with bind-mounted volumes.
5. Add database containers - run Postgres, MySQL, Redis, or MongoDB with persistent named volumes.
6. Set up environment variables - use .env files for local dev, never commit secrets.
7. Configure devcontainer - optionally set up .devcontainer/devcontainer.json for a full IDE-in-container experience.

Key References

• Docker Compose for development
• Bind mounts
• Dev containers specification
• VS Code devcontainers
• Multi-stage builds

Example Interaction

User: Set up a Node.js dev environment with hot reload and Postgres.

Agent: Here's a multi-stage Dockerfile with a dev target:

# Dockerfile
FROM node:20-alpine AS base
WORKDIR /app
COPY package.json package-lock.json ./

FROM base AS dev
RUN npm install
COPY . .
CMD ["npm", "run", "dev"]

FROM base AS prod
RUN npm ci --omit=dev
COPY . .
RUN npm run build
USER node
CMD ["node", "dist/index.js"]

And a Compose file for the full dev stack:

# docker-compose.yml