Multi Stage Dockerfile

What it does

This skill enables AI agents to generate and manage multi-stage Dockerfiles, which are used to build efficient container images by separating build-time dependencies from runtime dependencies. It supports creating optimized Docker images with minimal final size through techniques like caching and layer reuse.

When to use it

• You need to create a Docker image that includes build tools during the build process but doesn't require them at runtime.
• You want to reduce the final image size by removing unnecessary packages or dependencies after the build is complete.
• You're working on a project with multiple stages, such as compiling code in one stage and running it in another.

Key capabilities

• Generates multi-stage Dockerfiles with clear separation of build and runtime stages.
• Optimizes image layers for efficient caching and reuse.
• Supports common use cases like building Node.js, Python, or Go applications in containers.

Example prompts

• "Create a multi-stage Dockerfile for a Node.js application."
• "Write a Dockerfile that builds a Python app in one stage and runs it in another with minimal dependencies."
• "Generate a multi-stage Dockerfile that compiles a Go binary and copies it into a lightweight runtime image."

Tips & gotchas

• Ensure your base images are appropriate for each stage (e.g., use golang for the build stage and alpine for the runtime).
• Be mindful of how layers are structured to maximize caching efficiency during repeated builds.