Quick start

From nothing to a live server in four commands:

rusm new hello               # new project with a TypeScript HTTP component
cd hello
rusm build                   # components/ → wasm/
rusm serve                   # → http://127.0.0.1:8080
curl http://127.0.0.1:8080/  # "Hello from RUSM 👋"

--lang rust or --lang go scaffolds a Rust or Go component instead of TypeScript; --protocol ws or --protocol sse scaffolds a WebSocket or SSE handler instead of HTTP. See the rusm CLI reference for the full command set.

What just happened?

Four commands, and you're serving real HTTP from a sandboxed WebAssembly component. Here's what each one did:

• rusm new hello scaffolded a project: a rusm.toml manifest with a [[serve]] entry, a TypeScript component at components/api/index.ts (a web-standard fetch handler), a .gitignore, and a README — a working app, not an empty skeleton.
• rusm build compiled that component to ./wasm/ — Bun bundles the TypeScript and it's precompiled to QuickJS bytecode (no jco, no per-component engine). A Rust or Go component would compile to wasm32-wasip2 instead; same wasm/ output either way.
• rusm serve bound the [[serve]] listener to a real TCP port. Each request runs in a fresh sandboxed instance — process-per-request, so one slow or crashing request can never block or take down another.
• curl hit that port and got the component's response back over a real socket.

There's no resident request handler, no thread pool to size, no framework to learn — you wrote a fetch function and RUSM made it a server. From here, the same model scales to WebSocket and SSE, multiple components, supervision, and a cluster.

Scaffold a real app — the TODO board

Want a real app instead of hello world? Scaffold the full TODO board — HTTP CRUD, a live SSE feed, WebSocket chat, and a resident store service driven by a worker — in TypeScript, Rust, or Go:

rusm new board --template todo-board   # add --lang rust or --lang go (default: ts)
cd board && rusm build && rusm serve   # → open http://127.0.0.1:8080

Or scaffold the weather template — a native host function (a "custom bridge") called from your guest, in any language — rusm new forecast --template weather --lang ts; see Add your own functions.

Add components and bridges

Once you have a project, rusm generate adds to it without touching anything else:

rusm generate component payments --lang rust --protocol http  # add a Rust HTTP component
rusm generate component feed --protocol sse                   # add a TS SSE component
rusm generate bridge mailer --lang ts                         # add a TS host bridge

Where to go next

• Build an app — walks the full path: write a component, serve it over HTTP/WS/SSE, call other components, supervise, broadcast.
• Configuration reference — every rusm.toml table and field: [[serve]], [serve.routes], [capabilities.<name>], [components.<name>], env.
• Write a component — TypeScript, Rust, or Go, with the full Process API and serving patterns.