cloudflare-workers

Cloudflare Workers

Cloudflare Workers let you run JavaScript/TypeScript (or WASM) on Cloudflare's global edge network with near-zero cold starts. Workers execute in V8 isolates, not containers.

• Docs: https://developers.cloudflare.com/workers/
• Dashboard: https://dash.cloudflare.com/?to=/:account/workers
• CLI: wrangler (npx wrangler or npm i -g wrangler)
• Pulumi resource: cloudflare.WorkersScript (docs)

Quick Start

# Create a new Worker project
npx wrangler init my-worker
cd my-worker

# Develop locally
npx wrangler dev

# Deploy
npx wrangler deploy

Worker Script Structure (ES Modules)

export default {
  async fetch(request: Request, env: Env, ctx: ExecutionContext): Promise<Response> {
    return new Response("Hello from the edge!");
  },

  async scheduled(event: ScheduledEvent, env: Env, ctx: ExecutionContext) {
    // Cron trigger handler
  },
};

interface Env {
  MY_KV: KVNamespace;
  MY_R2: R2Bucket;
  MY_DB: D1Database;
  SECRET_KEY: string;
}

Key Bindings

Workers connect to other Cloudflare services via bindings declared in wrangler.toml:

Binding	Type	Use Case
KV	kv_namespaces	Key-value storage
R2	r2_buckets	Object storage
D1	d1_databases	SQL database
Durable Objects	durable_objects	Stateful coordination
Queues	queues	Message queues
AI	ai	Workers AI inference
Service	services	Worker-to-Worker calls
Secret	[vars] / secrets	Environment variables

Pulumi IaC

import * as cloudflare from "@pulumi/cloudflare";

const worker = new cloudflare.WorkersScript("my-worker", {
  accountId: accountId,
  name: "my-worker",
  content: workerScriptContent, // The JS/TS bundle as a string
  module: true, // ES modules format

  // Bindings
  kvNamespaceBindings: [
    {
      name: "MY_KV",
      namespaceId: myKvNamespace.id,
    },
  ],
  r2BucketBindings: [
    {
      name: "MY_R2",
      bucketName: myR2Bucket.name,
    },
  ],
  d1DatabaseBindings: [
    {
      name: "MY_DB",
      databaseId: myD1Database.id,
    },
  ],
  plainTextBindings: [
    {
      name: "ENV_VAR",
      text: "value",
    },
  ],
  secretTextBindings: [
    {
      name: "API_KEY",
      text: config.requireSecret("apiKey"),
    },
  ],
});

// Route the worker to a custom domain
const route = new cloudflare.WorkersRoute("my-route", {
  zoneId: zone.id,
  pattern: "api.example.com/*",
  scriptName: worker.name,
});

Limits

Limit	Free	Paid
Requests/day	100,000	Unlimited
CPU time/request	10ms	30s
Script size	1 MB	10 MB
Subrequests	50	1,000
KV reads/request	1,000	1,000

References

• Workers Docs
• Wrangler CLI
• Runtime APIs
• Bindings
• Pulumi WorkersScript