Announcing Lucet: Fastly’s native WebAssembly compiler and runtime
Lucet is designed to take WebAssembly beyond the browser, and build a platform for faster, safer execution on Fastly’s edge cloud. WebAssembly is already supported by many languages including Rust, TypeScript, C, and C++, and many more have WebAssembly support in development. We want to enable our customers to go beyond Fastly VCL and move even more logic to the edge, and use any language they choose. Lucet is the engine behind Terrarium, our experimental platform for edge computation using WebAssembly. Soon, we will make it available on Fastly’s edge cloud as well. A major design requirement for Lucet was to be able to execute on every single request that Fastly handles. That means creating a WebAssembly instance for each of the tens of thousands of requests per second in a single process, which requires a dramatically lower runtime footprint than possible with a browser JavaScript engine. Lucet can instantiate WebAssembly modules in under 50 microseconds, with just a few kilobytes of memory overhead. By comparison, Chromium’s V8 engine takes about 5 milliseconds, and tens of megabytes of memory overhead, to instantiate JavaScript or WebAssembly programs. With Lucet, Fastly’s edge cloud can execute tens of thousands of WebAssembly programs simultaneously, in the same process, without compromising security. The Lucet compiler and runtime work together to ensure each WebAssembly program is allowed access to only its own resources. This means that Fastly’s customers will be able to write and run programs in more common, general-purpose languages, without compromising the security and safety we’ve always offered.
(tags: lucet cdn edge-computing wasm webassembly fastly rust c c++ typescript)