Introducing tsrs: A Port of TypeScript to Rust

Cloudflare and VoidZero are working with Max Schwenk of Owner.com on tsrs, a Rust port of the TypeScript compiler. The project is being developed with the TypeScript team and sits inside the Oxc JavaScript compiler toolchain, not as a breakaway fork.

That distinction matters. The people behind tsrs say they want TypeScript’s own team to keep control of the language’s design and direction, while the Rust version stays tightly aligned with upstream. The goal is simple enough: less waiting for type checks, less memory burned, and a compiler that can fit into more places, including the browser.

The early numbers are eye-catching. Against TypeScript 7.0, tsrs is said to be up to 8x faster and use about 70% less memory when the same number of type check workers is used. TypeScript 7.1 beta already narrows that gap, reaching up to 2.5x the speed of TypeScript 7.0, and some of those gains were upstreamed from tsrs.

There’s a caution baked into the launch. The team says benchmark comparisons with other ports can get messy when they use different machine sizes or different defaults, so they worked with the TypeScript team to keep the measurements on the same configuration. By default, tsrs uses an adaptive setup that leans toward more memory in exchange for even more speed.

Cloudflare also wants this to matter beyond compiler bragging rights. The company points to WebAssembly and says Rust’s memory model makes it easier to move data between guest and host, which helps when running build systems in tight loops on Workers. That same approach, they argue, could eventually make fully sandboxed development environments viable in a browser, on embedded devices, or inside IoT apps. The project is still experimental, but it is already installable from npm as tsrs.