dacker_skill

Overview

This skill installs and uses Docker reliably, always referencing official Docker documentation for commands, install steps, and Dockerfile guidance. It supports Docker Desktop and Docker Engine installs, building and running containers, composing multi-service apps, and debugging common Docker CLI and daemon issues. Guidance is pragmatic and actionable, with links to canonical docs when version-specific detail is required.

How this skill works

The skill inspects the user platform and recommends the appropriate official installation path (Docker Desktop for macOS/Windows, Engine for Linux) and verifies the daemon by running a test container. For Dockerfile, CLI, and compose tasks it uses canonical Docker references to produce exact syntax and recommended workflows. When running in an environment that already exposes Docker (CI, test container), it uses the available docker CLI and host socket without attempting redundant installs.

When to use it

• User wants to install Docker on macOS, Linux, or Windows
• User needs help writing or debugging a Dockerfile or docker-compose.yaml
• Building, running, or troubleshooting containers and images
• Verifying Docker daemon connectivity or running the hello-world test
• Preparing containerized development or CI workflows

Best practices

• Always base install steps on the official Docker Get Docker and Engine install docs for the target OS
• Verify the daemon is running with docker run hello-world before troubleshooting commands
• Use stable host paths for volume mounts; avoid ephemeral temp directories for -v HOST:CONTAINER
• Prefer docker compose v2 (compose plugin) and put compose files in the project root
• For Linux, consider adding your user to the docker group via the official postinstall guide rather than using sudo everywhere

Example use cases

• Install Docker Desktop on macOS or Windows and start the daemon, or install Docker Engine on Ubuntu via the apt repository
• Build an image: docker build -t myapp . and run it with docker run -d -p 127.0.0.1:3000:3000 myapp
• Create and clean short-lived containers: docker run --rm alpine echo "Hello from Alpine"
• Bring up a multi-service app: docker compose up -d; follow logs with docker compose logs -f
• Troubleshoot daemon connectivity: confirm Docker Desktop is running or start systemd docker.service on Linux and then retry docker ps