ralph

Ralph

Autonomous AI-assisted development methodology that keeps specs and code in sync through intelligent iteration loops.

Based on Geoffrey Huntley's Ralph pattern with adaptations for Claude Code.

The Idea

Humans write specs (the "what"). The machine handles implementation (the "how").

specs/ ──► [planning loop] ──► IMPLEMENTATION_PLAN.md ──► [building loop] ──► code

• Specs are the source of truth
• Code is the derived artifact
• Fresh context per iteration prevents context debt
• Built-in quality gates create backpressure

Installation

1. Add the plugin to Claude Code

/plugin marketplace add eumemic/ralph

2. Install the CLI

Run the setup command in Claude Code:

/ralph-setup

This adds ralph to your PATH.

Usage

Initialize a project

ralph init

Creates:

• specs/ - Where you write specifications
• .ralph/config.yaml - Configuration
• .ralph/IMPLEMENTATION_PLAN.md - Generated task list

Write specs

Create markdown files in specs/ describing what you want to build. Focus on:

• What success looks like - Observable outcomes
• Acceptance criteria - Testable conditions
• Edge cases - What could go wrong
• Constraints - Performance, security, compatibility

Claude Code (with the Ralph plugin) can help you write specs through a structured conversation - just ask it to help you write a spec.

Run the planning loop

ralph plan

Analyzes your specs against the codebase and generates a prioritized implementation plan in .ralph/IMPLEMENTATION_PLAN.md.

Run the building loop

ralph build

Implements tasks one at a time, each iteration:

1. Picks ONE task from the plan
2. Writes test first
3. Implements
4. Validates
5. Commits
6. Restarts with fresh context

Environment variables

RALPH_MODEL=opus            # Main agent (default: opus)
RALPH_SUBAGENT_MODEL=sonnet # Subagents (default: sonnet)

Project Structure

your-project/
├── specs/                         # Commit this - your specifications
│   ├── feature-one.md
│   └── feature-two.md
├── .ralph/                        # Gitignore this - generated files
│   ├── config.yaml
│   └── IMPLEMENTATION_PLAN.md
└── src/

• specs/ should be committed to your repo - these are your project's requirements
• .ralph/ should be gitignored - it contains generated files and local config

Add to your .gitignore:

.ralph/

Configuration

Edit .ralph/config.yaml:

# Where to find specs (default: ./specs)
specs_dir: ./specs

# Or put them elsewhere
# specs_dir: ./docs/requirements

Commands

Command	Description
/ralph-init	Initialize Ralph in current project
/ralph-setup	Install ralph CLI to your PATH
/ralph-plan	Explain/run the planning loop
/ralph-build	Explain/run the building loop

How It Works

Planning Loop

1. Reads all specs
2. Studies existing codebase with parallel subagents
3. Performs gap analysis (spec vs implementation)
4. Generates prioritized task list
5. Repeats until plan stabilizes

Building Loop

1. Reads specs and plan
2. Picks highest priority incomplete task
3. Searches codebase ("don't assume not implemented")
4. Writes test first, then implements
5. Runs validation (tests, code review)
6. Commits on success
7. Exits - loop restarts with fresh context

Each iteration gets a clean 200K token context. No accumulated confusion.

Credits

• Original methodology: Geoffrey Huntley
• Playbook synthesis: Clayton Farr

License

MIT