@use-crux/cloudflare

@use-crux/cloudflare

Cloudflare Workers and Durable Object hosting for Crux Runtime and deployed Evals.

Install

pnpm add @use-crux/cloudflare @use-crux/core

Worker entry

Run crux runtime generate, then create one host from cloudflare/_crux/generated.ts, export its Durable Object class, and delegate Worker requests to its router:

import { createCloudflareEvalHost } from "@use-crux/cloudflare";
import { deployedEvals, runtimeTargets } from "./_crux/generated";

interface Env {
  CRUX_EVAL_HOST: DurableObjectNamespace;
  CRUX_EVAL_HOST_TOKEN: string;
}

const host = createCloudflareEvalHost<Env>({
  binding: "CRUX_EVAL_HOST",
  deploymentId: "production-eu",
  registry: deployedEvals,
  targets: runtimeTargets,
  token: (env) => env.CRUX_EVAL_HOST_TOKEN,
});

export const CruxEvalHost = host.DurableObject;
export default { fetch: host.fetch };

Bind CRUX_EVAL_HOST to CruxEvalHost in Wrangler and store the dedicated Eval-execute bearer as the CRUX_EVAL_HOST_TOKEN secret. Do not reuse browser, Devtools, feedback, or ingest credentials.

The default result store canonicalizes and chunks payloads inside Durable Object storage. To use R2, provide an explicit resultPayloads factory that implements Core's RuntimeResultPayloadPort; work records still commit only the content-addressed result reference.

Jobs are recovered through Durable Object alarms. waitUntil() and Cloudflare Queues are not part of the correctness path.

Point the local coordinator at this deployment with CRUX_EVAL_HOST_URL, CRUX_EVAL_HOST_DEPLOYMENT_ID, and the secret CRUX_EVAL_HOST_TOKEN. Cloudflare connection values are not inferred. The token must stay in environment/platform secrets and must not appear in config, generated registries, CLI arguments, plans, logs, errors, or fingerprints.

Runtime declaration

Declare the host in crux.config.ts with cloudflare(). The returned value is inert outside the generated Worker entry and fails with the standard host-only diagnostic if executed elsewhere.

import { config } from "@use-crux/core";
import { cloudflare } from "@use-crux/cloudflare";

export default config({ runtime: cloudflare() });

See the Cloudflare Workers Eval host guide for generated-entry and deployment setup.