# Cloudflare and VoidZero launch experimental Rust TypeScript checker with up to 8x vendor-reported speed The experimental tsrs compiler brings TypeScript type-checking into Rust and WebAssembly-oriented environments, but its reported speedups are vendor benchmarks and compatibility with official TypeScript remains a work in progress. Cloudflare and VoidZero are developing tsrs under Oxc with the TypeScript team. The early Rust checker claims up to 8x speed and 70% lower memory than TypeScript 7.0 under matched worker counts, but is not a drop-in stable compiler yet. - Status: Active - Published: 2026-10-21T19:16:44+13:00 - Updated: 2026-10-21T19:16:44+13:00 - Categories: Web Development, JavaScript, Developer Tools - Tags: JavaScript, Rust, TypeScript - Canonical HTML: https://beyondthe.news/dossiers/tsrs-rust-typescript-port-oxc-cloudflare-voidzero-experimental ## What changed On 20 October 2026 Cloudflare, VoidZero and collaborators announced tsrs, an experimental Rust port of the TypeScript compiler incubated within the Oxc JavaScript toolchain in coordination with TypeScript's maintainers. Cloudflare reports up to eightfold speed and about 70% lower memory use than TypeScript 7.0 in early matched-worker benchmarks. The project can be installed from npm with npm install tsrs and run using npx tsrs. The maintainers plan to merge the separate tsc-rs work, improve feature and diagnostic compatibility, and eventually add Language Server Protocol and source-map functionality. ## Why it matters Type-checking time and memory cost shape build times, CI spending and whether developers can run complete toolchains inside browser or sandboxed agent environments. A Rust implementation targets low-overhead WebAssembly execution, different from the official TypeScript team's Go-based native port. Builders should treat this as a promising experiment and benchmark it against their actual projects rather than replacing production checks on the basis of early headline numbers. ## A port, not a new TypeScript language fork The maintainers explicitly defer language design and semantics to the TypeScript team. Their challenge is keeping a second implementation behaviourally aligned as TypeScript evolves. The port is being incubated in Oxc, whose Rust tooling already covers linting and transformation workflows. ## The performance figures have a defined comparison Cloudflare reports up to 8x faster checks and approximately 70% less memory versus TypeScript 7.0 with the same number of type-check workers. It also says TypeScript 7.1 beta is already up to 2.5x faster than 7.0 in its tests. These are author-produced early benchmarks, not an independently reproduced industry-wide result; tsrs adaptive defaults may trade memory for additional speed. ## WebAssembly is the architectural reason for another port The official Go TypeScript compiler already offers major native speedups. Rust can be compiled to compact WebAssembly without bringing Go's runtime and garbage collector into the guest. That matters for browser-hosted IDEs, edge runtimes and isolated coding-agent environments, but production viability depends on feature coverage and compatibility. ## Migration should be experimental until compatibility matures The team acknowledges differences such as diagnostic ordering and plans to combine tsrs and tsc-rs, extend language-service support, and keep pace with upstream changes using automated tracking and tests. Run tsrs alongside an existing compiler in CI to compare diagnostics, memory and elapsed time; do not assume a passing experimental check matches the official compiler on all constructs. ## Key details - Announced October 20, 2026 by Cloudflare and VoidZero collaborators. - Incubated in Oxc, working with the official TypeScript team rather than forking language design. - Experimental npm package tsrs is available. - Up to 8x faster and ~70% lower memory versus TypeScript 7.0 are vendor-reported early benchmarks. - TypeScript 7.1 beta already shows substantial performance gains in the same announcement. - Stable feature, diagnostics and language-service parity not yet achieved. ## Builder takeaways - Try tsrs on a representative project alongside your existing tsc check, not instead of it. - Compare the same worker count and machine class when testing speed or memory. - Track differences in diagnostics and unsupported compiler options before adding it to release gates. - For browser/edge toolchains, evaluate WebAssembly size and isolation separately from raw type-check speed. ## What to watch - Merge with tsc-rs and Language Server Protocol support. - Independent project-scale performance and compatibility benchmarks. - Upstream TypeScript 7.1 performance improvements and possible Oxc integrations. ## Uncertainties - No independent reproduction of the 8x headline benchmark was found. - Compatibility matrix and stable-release timeline are incomplete. - WebAssembly runtime performance may differ from native Rust measurements. ## Sources - [Introducing tsrs: a Port of TypeScript to Rust](https://blog.cloudflare.com/typescript-rust-port/) — Cloudflare · primary engineering announcement · 2026-10-20T00:00:00+13:00. Project ownership, benchmark configuration, experimental install, limitations and future roadmap. - [JavaScript Weekly #807](https://javascriptweekly.com/issues/807) — JavaScript Weekly · specialist radar · 2026-10-21T00:00:00+13:00. Independent ecosystem discovery of the new Rust port; performance figures remain vendor-reported.