▸ about

One prompt.
One real build.

JustOne is a public challenge. You give Claude Code a single message. The agent ships a runnable project — no follow-ups, no edits, no second tries — and pushes the result to your GitHub. Then it's pinned here for everyone to see.

The rules

  1. 01

    One prompt locks the run.

    When you type /justone <your prompt>, the plugin writes justone/manifest.jsonwith your prompt + a SHA-256 hash. The hash is checked server-side at publish time. No edits after the lock.

  2. 02

    No follow-ups.

    The agent makes reasonable assumptions and ships. If the spec is ambiguous, it picks something specific and commits.

  3. 03

    Runnable or it doesn't count.

    The repo has to install and run. README with install + start commands is mandatory.

  4. 04

    Your code lives on your GitHub.

    We don't store source on our servers — only the manifest, the repo URL, and the image URLs. Your build is yours.

  5. 05

    Verified means verified.

    The gallery's ✓ verified badge means the API fetched justone/manifest.json from your raw GitHub URL, recomputed the prompt hash, and matched. No way to forge it without controlling the repo.

The plugin

JustOne ships as two Claude Code slash commands plus a skill: /justone to lock and build, /justone-publishto push and register. Pure Node helpers, no external dependencies. Cross-platform (cmd, PowerShell, bash, zsh, fish, Git Bash — we tested all of them).

Source & install →Sign in to publish

Tech

agent
Claude Code (v0.1 — Codex coming later)
gallery
Next.js · Tailwind v4 · Supabase Postgres
hosting
Vercel
storage
user GitHub (we hold metadata only)
verification
SHA-256 prompt hash + HMAC submission
license
MIT (plugin)

Privacy

Sign-in uses GitHub OAuth. We request read:user user:email public_repo— the minimum to verify you own the repo you're publishing. We never read your private repos. CLI tokens are stored on our side as a SHA-256 hash; the plaintext is shown once and lives only on your machine at ~/.justone/credentials.

Made by

JustOne is an experiment. If something breaks, file an issue on the plugin repo. The source is MIT licensed.

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