I Used Ralph to Build a Full Feature – Here's How It Works

Ralph is embarrassingly simple: a bash loop that keeps prompting Claude until the work is done. One feature per iteration, a commit after each one, and a to-do list the agent updates itself. I used it to ship a full prompt history feature for my AI tattoo app, and the video shows every iteration.

What's inside

• Why small looped tasks beat one giant prompt
• The bash script that caps iterations so tokens stay under control
• Structuring features as a JSON to-do list the agent can update
• How each fresh agent picks up context from commits and progress notes
• Automatic commits to a dedicated branch for easy rollback
• Running it yourself: ./ralph.sh 12 and walk away

Resources

BookFrom Idea to App Store with Claude Code

The prompting mental model behind workflows like Ralph, from idea to a shipped app.