Create and build an API

1. Create the application

From the directory where you keep projects, run:

bunx create-relkit@latest relkit-cli-demo
cd relkit-cli-demo
cp .env.example .env

The generator installs the minimal starter and its local CLI. If prompted, confirm the new destination. Keep this terminal in relkit-cli-demo for the remaining commands. For an existing minimal application, use its root directory and keep its current .env.

Creation options explains deferred installation, Git initialization, and supported starter choices.

2. Add an endpoint

Inspect the command, then create a new route:

bun run relkit add route --help
bun run relkit add route /ping --mode route

The second command creates src/routes/ping/route.ts with a GET handler that returns { "ok": true }. The directory determines the URL. --mode route selects a standalone HTTP handler, which is useful for this small response. For business operations with input and output schemas, use a service-backed route.

If /ping already exists, choose a new path and use that path in the requests below. Scaffolding rejects collisions instead of overwriting existing files.

3. Check the application

Run these checks from the same directory:

bun run check
bun run typecheck
bun run test

All three commands should finish successfully. check validates the application’s structure, typecheck checks TypeScript, and test runs the starter tests. Adding a route does not generate tests for that route; you will verify its response next. See Testing when adding behavior of your own.

4. Run and call the endpoint

Start development:

bun run dev

Keep it running. When the server is ready, send a request from the second terminal:

curl -i http://localhost:3000/ping

Expect HTTP 200 and this JSON body:

{ "ok": true }

If connection fails, wait for readiness and check Terminal 1 for diagnostics. If the response is 404, check the route directory and whether validation succeeded. Troubleshooting explains how to follow diagnostics back to the file to repair.

5. Build and run production output

In Terminal 1, press Ctrl+C to stop development. Build and start from the same application directory:

bun run build
bun run start

The build writes .relkit/build; start runs that output. When it is ready, repeat the request in Terminal 2:

curl -i http://localhost:3000/ping

Expect HTTP 200 and { "ok": true } again. Production does not watch source changes: rebuild after editing. Press Ctrl+C in Terminal 1 when finished. Building and starting locally do not deploy the application.