web-app5 min

Your First Web Server

Every web application starts with a server. In Clean Language you declare your routes with a simple, readable syntax — and the Frame framework handles compilation, routing, and everything else.

A Clean Language server has two parts: the plugins it uses and the endpoints it exposes.

plugins:\n    frame.server\n\nendpoints server:\n    GET "/" :\n        return http.respond(200, "text/plain", "Hello, World!")\n\n    GET "/about" :\n        return http.respond(200, "text/plain", "About this server")

Server running on http://localhost:8080\nGET /       → 200 Hello, World!\nGET /about  → 200 About this server

The plugins: block tells Clean Language which framework modules to load. endpoints server: declares your HTTP routes. Each route is a method + path. http.respond(status, contentType, body) sends the response.

Save the file as server.cln and run it with cleen:

cleen run server.cln

Server started on http://localhost:8080

cleen run compiles your file and starts the server. Open http://localhost:8080 in your browser to see Hello, World! — no build step, no config, no boilerplate.

Quick recap

plugins: declares which framework modules your server needs
endpoints server: defines your HTTP routes
http.respond(status, contentType, body) — status 200 means success
cleen run server.cln compiles and starts your server in one step