Rails DevContainer

A fully-featured development container configuration for Ruby on Rails projects with integrated tools and services.

Features

• Pre-configured Ruby on Rails development environment
• Docker Compose setup with Selenium for system testing
• GitHub CLI, Node.js, Python, and AWS CLI pre-installed
• Automatic Ruby version synchronization
• MCP (Model Context Protocol) server integration
• Volume mounts for SSH, AWS, GitHub, and Claude configurations

Requirements

• Docker Desktop or Docker Engine
• Visual Studio Code with Dev Containers extension
• Git

Quick Start

1. In your Rails project directory, add this repository as a git subtree:

   git subtree add --prefix=.devcontainer --squash git@github.com:douhashi/devcontainer-rails.git main

Visual Studio Code

2. Open your Rails project in VS Code:

   code .

3. When prompted, click "Reopen in Container" or run the command "Dev Containers: Reopen in Container"

4. Wait for the container to build and post-create scripts to complete

DevContainer CLI

2. Rebuild and start the development container:

   .devcontainer/bin/rebuild
   .devcontainer/bin/up

3. The container will build and start with all configured services

Updating DevContainer

To update the DevContainer configuration with the latest changes from the upstream repository:

git subtree pull --prefix=.devcontainer --squash git@github.com:douhashi/devcontainer-rails.git main

Configuration

Ruby Version

The Ruby version is automatically synchronized from .tool-versions file. To change it:

1. Update .tool-versions in your Rails project
2. Run sync-ruby-version.sh to update the DevContainer configuration
3. Rebuild the container

Services

• App: Main Rails application container (ports 5100, 3036)
• Selenium: Chrome browser for system tests (port 4444)

Environment Variables

• KAMAL_REGISTRY_USERNAME: Docker registry username for Kamal deployments
• KAMAL_REGISTRY_PASSWORD: Docker registry password for Kamal deployments
• VITE_RUBY_HOST: Vite development server host (default: 0.0.0.0)
• SELENIUM_URL: Selenium server URL for system tests

Scripts

• post-create.sh: Runs after container creation (installs packages, tools, Rails setup)
• post-attach.sh: Runs each time you attach to the container
• sync-ruby-version.sh: Updates DevContainer Ruby version from .tool-versions

License

This project is licensed under the MIT License - see the LICENSE file for details.