This repository contains a collection of dev container Features for use with Dev Containers.

This repository contains the following Features:

• ralph - AI Agentic Loop shell runner for spec-driven development workflows
• lefthook - Git hooks manager for fast and powerful Git hook workflows
• opencode-ralph - [Deprecated] ralph + opencode installed via devcontainer features. Maintained only for legacy purposes, but consider using the ralph Feature instead.

Each sub-section below shows a sample devcontainer.json alongside example usage of the Feature.

Installs the ralph script for running AI Agentic Loop workflows.

{
    "image": "mcr.microsoft.com/devcontainers/base:ubuntu",
    "features": {
        "ghcr.io/iyaki/devcontainer-features/ralph:1": {
            "version": "latest"
        }
    }
}

$ ralph --help

# Ralph script installed and ready to use

Installs lefthook from GitHub Releases.

{
    "image": "mcr.microsoft.com/devcontainers/base:ubuntu",
    "features": {
        "ghcr.io/iyaki/devcontainer-features/lefthook:2": {
            "version": "latest"
        }
    }
}

$ lefthook version

# Lefthook installed and ready to use

Similar to the devcontainers/features repo, this repository has a src folder. Each Feature has its own sub-folder, containing at least a devcontainer-feature.json and an entrypoint script install.sh.

An implementing tool will composite the documented dev container properties from the feature's devcontainer-feature.json file, and execute in the install.sh entrypoint script in the container during build time. Implementing tools are also free to process attributes under the customizations property as desired.