Get Started

Install Retro.

Two paths: the Claude Code plugin (one prompt, hands-off) or the standalone CLI (clone, build, alias). Both ship the same parser, validator, and skill — pick whichever matches how you work.

Path 1 — One prompt, hands-off (recommended)

If you're running Claude Code, paste the prompt below into any session. The agent will install the Retro marketplace plugin, register the using-retro auto-load skill, and verify everything works. After it finishes, restart Claude Code so the new skill registers.

I want to set up Retro on this machine. Its public repo is
https://github.com/Tensorpunk-Labs/retro and its product site
is https://retrolang.dev.

Please:
  1. Add the marketplace: /plugin marketplace add Tensorpunk-Labs/retro
  2. Install the plugin: /plugin install retro@tensorpunk-labs-retro
  3. Verify the /retro slash command is available.
  4. Confirm the using-retro auto-load skill is registered —
     it should activate when I open a .retro file or mention
     Retro / retrograde development.
  5. Briefly explain how I use the /retro command to scaffold
     my first program.

If any step fails, stop and tell me what went wrong before continuing.

That's it. The plugin gives you a guided /retro command for scaffolding programs and the using-retro skill that auto-loads whenever you're working in a .retro file.

Marketplace skill availability. The retro plugin is published in the Tensorpunk-Labs marketplace. Once added, it appears in /plugin install as retro@tensorpunk-labs-retro. The bundled using-retro skill is auto-loaded by Claude Code when relevant — no manual activation needed.

Path 2 — Standalone CLI

If you want the CLI directly, or you're not using Claude Code:

Prerequisites

Clone, install, build

$ git clone https://github.com/Tensorpunk-Labs/retro
$ cd retro
$ pnpm install
$ pnpm build

Alias the CLI

The retro binary is not on PATH by convention. Either alias it in your shell config:

$ alias retro="node $(pwd)/packages/cli/dist/index.js"

Or invoke directly: node packages/cli/dist/index.js --help.

Verify

$ retro --help

You should see eight commands: init, validate, status, emit, delta, versions, and viz.

Your first program

From any directory, scaffold a .retro file from a plain-English idea:

$ retro init "collaborative whiteboard with CRDT sync"

Open the file. You'll see @future, @shape, @flow, and @impl placeholders. Fill @future first — the guarantees and constraints. Then @shape — the modules and how they connect. Then @flow — the inter-module choreography. Finally @impl — the real code.

Validate as you go:

$ retro status whiteboard.retro             # level-completion overview
$ retro validate whiteboard.retro           # structural + semantic check
$ retro emit whiteboard.retro --out ./src   # extract @impl to real files

What's next