docker-development

Documentation

# Docker Development Skill

[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
[![Claude Code Compatible](https://img.shields.io/badge/Claude%20Code-Compatible-blue)](https://claude.ai/claude-code)

Agent Skill for Docker image development - Dockerfile best practices, CI testing patterns, and Docker Compose orchestration.

## Features

- **Dockerfile Best Practices** - Multi-stage builds, layer optimization, security
- **CI Testing Patterns** - Test Docker images reliably in CI pipelines
- **Docker Compose** - Service orchestration, health checks, networking
- **Docker Bake** - Multi-platform builds with BuildKit
- **Security** - Vulnerability scanning, non-root users, secret management

## Automatic Triggers

This skill activates automatically when working with:

| File Pattern | Description |
|--------------|-------------|
| `Dockerfile`, `Dockerfile.*`, `*.dockerfile` | Container image definitions |
| `docker-compose.yml`, `compose.yml` | Multi-container orchestration |
| `docker-bake.hcl` | BuildKit bake configurations |
| `.dockerignore` | Build context optimization |

## Installation

### Claude Code (Recommended)

```bash
claude mcp add-skill netresearch/docker-development-skill
```

### Manual

Copy `skills/docker-development/SKILL.md` to your Claude Code skills directory.

## Usage

The skill activates automatically when working on:
- Dockerfile development
- Docker Compose configurations
- Docker Bake multi-platform builds
- CI/CD pipelines for container images
- Container troubleshooting

### Example Prompts

- "Create a multi-stage Dockerfile for a Node.js app"
- "Set up GitHub Actions to build and push Docker images"
- "Why is my nginx config test failing in CI?"
- "Add health checks to my docker-compose.yml"
- "Create a docker-bake.hcl for multi-platform builds"

## Key Patterns

### Testing Images with Entrypoints

```bash
# Bypass entrypoint for direct testing
docker run --rm --entrypoint php myimage -v
```

### Testing nginx Configs in Isolation

```bash
# Mock upstream DNS
docker run --rm --add-host backend:127.0.0.1 nginx-image nginx -t
```

### Compose Validation in CI

```bash
# Create .env before validation
cp .env.example .env
sed -i 's/PLACEHOLDER/test_value/g' .env
docker compose config > /dev/null
```

## References

Extended documentation in `skills/docker-development/references/`:

- `ci-testing.md` - Comprehensive CI testing patterns

## Contributing

1. Fork the repository
2. Create a feature branch
3. Submit a pull request

## License

MIT License - see [LICENSE](LICENSE)

## Author

[Netresearch DTT GmbH](https://www.netresearch.de)
Keywords

Documentation
