ナレッジベース
Docker
Docker containerization guide covering Dockerfile authoring, multi-stage builds, image optimization, security hardening, Docker Compose for local development, and .dockerignore best practices. Use PROACTIVELY when creating or editing Dockerfiles, docker-compose.yml files, containerizing an application, or troubleshooting Docker build and runtime issues. **PROACTIVE ACTIVATION**: Invoke on Dockerfile, docker-compose, 'containerize', 'docker build', 'container won't start', or any task involving images, volumes, or container networking. **USE CASES**: New Dockerfile, optimizing image size, adding health checks, setting up multi-service local dev environment, fixing build failures, securing containers.