1. Install RivetKit.
2. Define a registry with `setup({ use: { /* actors */ } })`.
3. Expose `registry.serve()` or `registry.handler()` (serverless) or `registry.startRunner()` (runner mode).
4. Verify `/api/rivet/metadata` returns 200 before deploying.
5. Configure Rivet Cloud or self-hosted engine.
6. Integrate clients (JavaScript, React, Swift).
7. Deploy to Rivet Cloud or self-hosted environment.