Ralphing

Ralph is an autonomous AI coding loop that ships features while you sleep. Each iteration runs in a fresh context window, while memory persists through git history and text files.

When to Use

When the user wants to implement a multi-story feature autonomously, or mentions "ralph", "ralphing", or "autonomous loop".

Workflow

Step 1: Get the PRD

The user provides a PRD file, or you help them create one. Ask:

1. Do you have a PRD already, or should we create one together?
2. What's the repo path?
3. What's the test command? (e.g., bundle exec rake, npm test)
4. How many iterations max? (default: 25)

PRD Format

# PRD

Branch: `<branch-name>`

## Stories

### US-001: <Story title>

- [ ] <Acceptance criterion>
- [ ] <Acceptance criterion>

### US-002: <Story title>

- [ ] <Acceptance criterion>

Guidelines for stories:

• Small: Must fit in one context window
• Explicit criteria: Avoid vague ("Users can log in"), prefer specific checks
• Story order = priority (first = highest)

Note: Ralph is typically run in a git worktree. If already on the correct branch (or detached HEAD), the branch checkout is skipped.

Step 2: Start the Loop

~/.claude/skills/ralphing/assets/ralph.sh start <repo_path> <prd.md> [max_iterations] [test_cmd]

This returns a session directory (e.g., /tmp/ralph/ABC123-...) and runs the loop in the background.

Step 3: Monitor Progress

Poll the session status periodically:

~/.claude/skills/ralphing/assets/ralph.sh status <ralph_dir>

This outputs:

• status: running, complete, or failed
• iteration: current/max iterations
• Full contents of progress.txt

Keep polling until status is complete or failed.

How the Loop Works

1. start copies PRD, generates prompt, checks out branch (if needed), and spawns background process
2. Background loop: agent implements story -> commits -> runs tests
3. If tests fail, reverts commit and retries (progress.txt preserved)
4. Exits when agent signals <promise>COMPLETE</promise> or max iterations reached
5. Parent agent polls status to observe progress without blocking

Resources

• assets/ralph.sh - the loop script (start/status commands)
• assets/prompt.md - prompt template (uses <RALPH_DIR> placeholder)