Cloudflare Workers SDK

Cloudflare Workers SDK (wrangler) is a free and open-source command-line tool for building, testing, and deploying serverless applications on Cloudflare Workers, a serverless execution environment that runs on Cloudflare's global edge network (300+ cities across 100+ countries). Cloudflare was founded by Matthew Prince, Lee Holloway, and Michelle Zatlyn in 2009. The Workers platform launched in 2017, with wrangler created by the Cloudflare Workers team. Key features: edge deployment: deploy code to Cloudflare's global network where it runs milliseconds from end users. Workers run on Cloudflare's V8 isolates (not containers or VMs), enabling near-zero cold start times and sub-millisecond execution. JavaScript, TypeScript, Rust, C, C++, and Python: Workers support multiple languages. JavaScript/TypeScript code runs directly in V8. Rust, C, and C++ compile to WebAssembly. Python uses Pyodide (CPython compiled to Wasm). Wrangler CLI: the primary tool for development. wrangler dev starts a local dev server that emulates the Workers runtime. wrangler deploy deploys to production. wrangler tail streams real-time logs. wrangler generate scaffolds new projects from templates. Project configuration: wrangler.toml defines the Worker's name, main entry point, compatibility date, environment bindings (KV namespaces, D1 databases, R2 buckets, Durable Objects, Queues, AI), and deployment settings. Key-value storage: Workers KV is a global, eventually-consistent key-value store for configuration data and cached responses. R2: S3-compatible object storage with zero egress fees. D1: SQLite-based serverless database. Durable Objects: stateful, strongly-consistent objects with WebSocket support for real-time applications. Queues: managed message queues for asynchronous processing. Workers AI: run ML models (LLMs, image classification) on the edge. TypeScript/Rust. Apache-2.0.