workerd is a JavaScript and WebAssembly server runtime based on the same code that powers Cloudflare Workers.
It can be used to self-host Workers applications, develop and test them locally, or build programmable forward and reverse HTTP proxies.
The runtime follows web platform standards and supports dividing applications into independently deployable nanoservices. These services can communicate within the same thread and process, avoiding much of the overhead associated with conventional networked microservices.
workerd is designed for server deployments and uses capability-based bindings to connect services and external resources. It supports compatibility dates, allowing applications to retain the API behaviour associated with an earlier Cloudflare Workers release.
This is free and open source software.
Key Features
- Runs JavaScript and WebAssembly server applications.
- Uses the same core runtime technology as Cloudflare Workers.
- Self-hosts applications developed for the Cloudflare Workers platform.
- Supports local development and testing of Workers applications.
- Functions as a programmable forward or reverse HTTP proxy.
- Provides standards-based web APIs including fetch().
- Divides applications into independently deployable nanoservices.
- Allows services to communicate through efficient local function calls.
- Uses capability-based bindings instead of global namespaces.
- Supports compatibility dates for maintaining earlier API behaviour.
- Uses configuration files written in Cap’n Proto text format.
- Supports socket activation and inherited sockets for systemd deployments.
- Runs on Linux and macOS on x86-64 and ARM64 systems.
- Supports Windows on x86-64 systems.
- Offers prebuilt binaries through npm.
Website: github.com/cloudflare/workerd
Support:
Developer: Cloudflare
License: Apache License 2.0
workerd is written in C++. Learn C++ with our recommended free books and free tutorials. Learn JavaScript with our recommended free books and free tutorials. Learn TypeScript with our recommended free books and free tutorials.
Related Software
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|---|---|
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| Bun | Fast JavaScript runtime designed as a drop-in replacement for Node.js. |
| Deno | Simple, modern and secure runtime for JavaScript and TypeScript |
| WasmEdge | High-performance, and extensible WebAssembly runtime |
| workerd | JavaScript and WebAssembly server runtime |
| LLRT | Designed for fast, resource-efficient serverless applications |
| txiki.js | Small and powerful JavaScript runtime |
| JerryScript | JavaScript engine for the Internet of Things |
| GraalJS | ECMAScript-compliant JavaScript engine |
| Window.js | JavaScript runtime for desktop graphics programming |
| Blueboat | Multi-tenant serverless JavaScript runtime |
| lo | Successor project to Just |
| StarlingMonkey | SpiderMonkey-based JavaScript runtime |
| Just | Very small v8 JavaScript runtime |
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