# Extend Docker Environment

Adds custom tools and personal settings to Docker through a user Dockerfile.

- Repository: https://github.com/coleam00/Archon (23799 stars)
- Category: DevOps
- License: MIT
- Last updated: 2026-10-31
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add coleam00/Archon --skill docker-extend -g -a claude-code -y`
Codex: `npx skills add coleam00/Archon --skill docker-extend -g -a codex -y`
Cursor: `npx skills add coleam00/Archon --skill docker-extend -g -a cursor -y`
Gemini CLI: `npx skills add coleam00/Archon --skill docker-extend -g -a gemini-cli -y`

## Description

Use when: User wants to extend Docker with custom tools, personalize the Docker environment, or set up user-specific Docker customization. Triggers: 'extend docker', 'docker-extend', 'add tools to docker', 'customize docker', 'add my tools to the container', 'personalize docker setup', 'docker user setup', 'install tools in docker'. Does: Interactively sets up Dockerfile.user and docker-compose.override.yml so users can add personal tools to their Docker environment without affecting maintainer files or committing user-specific config to git.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# Docker Extend

Sets up personal Docker tool customization using the project's gitignored override pattern.
Your `Dockerfile.user` and `docker-compose.override.yml` are yours, never committed to git.

## Step 1: Detect Context

Determine if the user is in dev (source build) or deploy (GHCR) mode:

!`if [ -f docker-compose.yml ] && grep -q 'build: \.' docker-compose.yml 2>/dev/null; then echo "DEV_MODE: Building from source (root docker-compose.yml)"; elif [ -f deploy/docker-compose.yml ]; then echo "DEPLOY_MODE: Using GHCR image (deploy/docker-compose.yml)"; else echo "UNKNOWN_MODE: No docker-compose.yml found in root or deploy/"; fi`

**Decision:**
- `DEV_MODE` → work with `Dockerfile.user` + `docker-compose.override.yml` (repo root)
- `DEPLOY_MODE` → work with `deploy/Dockerfile.user` + `deploy/docker-compose.override.yml`
- `UNKNOWN_MODE` → ask the user which directory their `docker-compose.yml` lives in before proceeding

## Step 2: Check Current State

**DEV_MODE, check root files:**

!`echo "=== Dockerfile.user ===" && (cat Dockerfile.user 2>/dev/null || echo "(not found, will create from example)") && echo "" && echo "=== docker-compose.override.yml ===" && (cat docker-compose.override.yml 2>/dev/null || echo "(not found, will create from example)")`

**DEPLOY_MODE, check deploy/ files:**

!`echo "=== deploy/Dockerfile.user ===" && (cat deploy/Dockerfile.user 2>/dev/null || echo "(not found, will create from example)") && echo "" && echo "=== deploy/docker-compose.override.yml ===" && (cat deploy/docker-compose.override.yml 2>/dev/null || echo "(not found, will create from example)")`

**If both files already exist:** Skip to Step 4 (add tools).
**If files are missing:** Proceed to Step 3 (copy from examples).
**If example files are missing too:** Tell the user the project hasn't added the example files yet and to check with the maintainers or the docs.

## Step 3: Copy Example Files

The rest: https://github.com/coleam00/Archon/blob/HEAD/.claude/skills/docker-extend/SKILL.md