cf-workerz

cf-workerz brings Zig's performance and safety to the Cloudflare Workers platform. Write your edge functions in Zig, compile to WebAssembly, and deploy with the standard Cloudflare toolchain. The resulting WASM binary is typically 10-15KB — orders of magnitude smaller than equivalent JavaScript bundles.

The library provides idiomatic Zig bindings for the entire Workers runtime API: storage (KV, R2, D1), caching, message queues, Workers AI, Durable Objects, WebSockets, and Web Crypto. It includes a built-in Router with middleware support, and uses JSPI (JavaScript Promise Integration) for ergonomic async operations.

const std = @import("std");
const cf = @import("cf-workerz");

const Router = cf.Router;

fn onRequest(allocator: std.mem.Allocator, ctx: *cf.FetchContext) !*cf.Response {
    var router = Router.init(allocator, ctx);

    router.get("/api/hello", handleHello);
    router.get("/api/user/:id", handleUser);

    return router.serve();
}

fn handleHello(ctx: *FetchContext) void {
    // Use ctx.param() shorthand for path parameters
    const name = ctx.param("name") orelse "World";

    // ctx.json() with anonymous struct
    ctx.json(.{
        .message = "Hello!",
        .name = name,
    }, 200);
}