Bun
Orizon detects Bun projects and runs them on the Bun runtime — fast installs, fast cold starts.
How Bun is detected
Orizon recognises a Bun app from a bun.lockb / bun.lock lockfile and Bun-specific configuration, and builds it with Bun rather than Node. Dependencies are installed with Bun and your start script runs under the Bun runtime.
The PORT contract
Like any server app on Orizon, your Bun server must listen on the port from the PORT environment variable. Orizon runs the container with PORT=3000 and routes public traffic to it.
const server = Bun.serve({
port: process.env.PORT ?? 3000,
fetch(req) {
return new Response("Hello from Bun on Orizon");
},
});Single-node Bun deploys serialize — a concurrent deploy while one is in flight returns a
409. Wait for the current deploy to finish, then trigger the next.