Claude-Skills docker-development

install

source · Clone the upstream repo

git clone https://github.com/borghei/Claude-Skills

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/borghei/Claude-Skills "$T" && mkdir -p ~/.claude/skills && cp -r "$T/engineering/docker-development" ~/.claude/skills/borghei-claude-skills-docker-development && rm -rf "$T"

manifest: engineering/docker-development/SKILL.md

source content

Docker Development

Category: Engineering Domain: Container Development & Optimization

Overview

The Docker Development skill provides automated analysis of Dockerfiles and docker-compose configurations. It identifies layer optimization opportunities, security issues, best practice violations, and compose service misconfigurations. Use this skill to enforce container standards across your team and catch issues before they reach production.

Quick Start

# Analyze a Dockerfile for best practices
python scripts/dockerfile_analyzer.py --file Dockerfile

# Analyze with JSON output
python scripts/dockerfile_analyzer.py --file Dockerfile --format json

# Validate a docker-compose file
python scripts/compose_validator.py --file docker-compose.yml

# Check for port conflicts across compose files
python scripts/compose_validator.py --file docker-compose.yml --check-ports

Tools Overview

dockerfile_analyzer.py

Analyzes Dockerfiles for best practices, security issues, and optimization opportunities.

Feature	Description
Layer optimization	Detects unnecessary layers, recommends combining RUN statements
Multi-stage analysis	Validates multi-stage build patterns and final image size
Security scanning	Flags running as root, use of latest tags, exposed secrets
Base image checks	Recommends smaller base images (alpine, distroless, slim)
Cache optimization	Identifies poor layer ordering that breaks Docker cache

# Full analysis
python scripts/dockerfile_analyzer.py --file Dockerfile

# Security-focused scan
python scripts/dockerfile_analyzer.py --file Dockerfile --security-only

# JSON output for CI integration
python scripts/dockerfile_analyzer.py --file Dockerfile --format json

compose_validator.py

Validates docker-compose files for correctness, dependency issues, and port conflicts.

Feature	Description
Schema validation	Checks compose file structure and syntax
Dependency graph	Validates depends_on chains for circular dependencies
Port conflict detection	Identifies duplicate host port bindings
Volume mount checks	Validates volume paths and mount configurations
Network analysis	Checks network definitions and service connectivity

# Full validation
python scripts/compose_validator.py --file docker-compose.yml

# Check port conflicts only
python scripts/compose_validator.py --file docker-compose.yml --check-ports

# JSON output
python scripts/compose_validator.py --file docker-compose.yml --format json

Workflows

Dockerfile Review Workflow

Analyze - Run dockerfile_analyzer.py against the target Dockerfile
Review findings - Address critical security issues first (root user, secrets)
Optimize layers - Combine RUN statements, reorder for cache efficiency
Validate base images - Switch to minimal base images where possible
Re-analyze - Confirm improvements and verify no regressions

Compose Validation Workflow

Validate structure - Run compose_validator.py for syntax and schema checks
Check dependencies - Review service dependency graph for circular refs
Audit ports - Ensure no host port conflicts across services
Review volumes - Confirm volume mounts are correct and necessary
Network review - Verify service isolation and connectivity

CI Integration Workflow

# Example GitHub Actions step
- name: Docker Lint
  run: |
    python scripts/dockerfile_analyzer.py --file Dockerfile --format json > results.json
    python scripts/compose_validator.py --file docker-compose.yml --format json >> results.json

Reference Documentation

Docker Best Practices - Comprehensive guide to Dockerfile and Compose patterns

Common Patterns Quick Reference

Pattern	Good	Bad
Base image	`FROM python:3.12-slim`	`FROM python:latest`
User	`USER appuser`	Running as root
Layer combining	`RUN apt-get update && apt-get install -y pkg`	Separate RUN for update and install
COPY ordering	Copy requirements first, then code	Copy everything at once
Multi-stage	Use builder stage + minimal runtime	Single stage with build tools
Secrets	Use build secrets or env at runtime	`COPY .env .` or `ENV SECRET=value`
Health checks	`HEALTHCHECK CMD curl -f http://localhost/`	No health check defined
.dockerignore	Include node_modules, .git, etc.	No .dockerignore file

Compose Patterns

Pattern	Good	Bad
Restart policy	`restart: unless-stopped`	No restart policy
Resource limits	`deploy.resources.limits` set	Unlimited resources
Named volumes	`volumes: [db-data:/var/lib/postgresql]`	Anonymous volumes
Networks	Explicit network definitions	Default bridge only
Environment	`env_file: .env`	Inline secrets in compose