Seeking Advice on Tree-Shaking for Cloudflare Worker Build Script

// src/main.ts
import { Effect } from "effect";
export default {
  async fetch(
    request: Request,
    env: Env,
    ctx: ExecutionContext,
  ): Promise<Response> {
    const result = await Effect.runPromise(
      Effect.gen(function* (_) {
        yield* _(Effect.sleep(1000));
        return `Hello ${request.cf?.city ?? "World"}! env: (${Object.keys(env).join(", ")})`;
      }),
    );
    return new Response(result);
  },
} satisfies ExportedHandler<Env>;