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Cloudflare has announced tsrs, a Rust port of the TypeScript compiler. It reports type checking up to 8x faster than TypeScript 7, with about 70% less memory usage. Support for all TypeScript features, including the Language Server Protocol, is planned, but compatibility should be verified before considering migration.

Key points#

  • According to Cloudflare, type checking is up to 8x faster and memory usage is about 70% lower than with the Go-based TypeScript 7.
  • According to VoidZero, tsrs is being developed in close collaboration with the TypeScript team and is not a TypeScript fork.
  • WebAssembly support enables execution in browsers and Cloudflare Workers, but deployment readiness needs verification.
  • Support for all TypeScript features, LSP support, and integration into the Oxc toolchain are planned.

What tsrs offers#

Announced in October 2026, tsrs brings a Rust implementation to the TypeScript compiler toolchain. VoidZero, which is involved in development, describes the project as a port rather than a fork.

This distinction signals an intent to work in step with TypeScript rather than establish an independent language direction. It does not, however, mean that every compiler option, diagnostic, and editor feature already behaves identically.

The immediate reason to evaluate tsrs is faster type checking with less memory. For projects where type checking accounts for a large share of continuous integration runtime, the reported gains warrant a comparison under equivalent conditions.

Read the benchmarks carefully#

Cloudflare’s published type-checking benchmarks report up to an 8x speedup and about a 70% reduction in memory usage compared with TypeScript 7. These are vendor-reported figures, not a guarantee of the same improvements across all repositories.

The comparison also includes TypeScript 7.1 beta. According to the report provided, this version is about 2.5x faster than TypeScript 7, but tsrs is faster still in the published results. The headline “8x” should therefore be treated as a comparison with TypeScript 7, not applied to 7.1.

The materials provided lack enough benchmark detail to predict results for individual projects. Before using these figures to estimate capacity or costs, check the repositories, compiler settings, hardware, and memory measurement methods used.

Try it on your own project#

VoidZero provides the following command to get started.

snippet.txt
npx tsrs

Use a disposable checkout or evaluation branch, and check the package’s latest instructions before running it. The announcement does not establish that tsrs supports all existing TypeScript command-line options or project configurations.

A useful evaluation requires these four checks.

  • Record the exact compiler versions and use the same repository revision.
  • Compare reported errors, including their locations and diagnostic messages.
  • Measure runtime and peak memory usage under equivalent conditions.
  • Repeat measurements to check whether the differences are consistent.

Faster execution is of little value if it skips checks your project needs. Investigate missing diagnostics and unsupported settings before treating a shorter runtime as a success.

Browser and Workers support#

Because Rust can compile to WebAssembly, tsrs could run in browser-based development tools and Cloudflare Workers. VoidZero’s announcement explicitly highlights both environments.

This could allow TypeScript tools to run close to web editors or within hosted development services. Cloudflare has also announced native Rust support in Workers, adding another related execution option.

These capabilities still require validation for each deployment target. The report provided does not establish package size, startup time, filesystem requirements, or runtime limits when running the full type-checking process. Running in a browser and providing a production-ready browser development environment are separate milestones.

Full feature support is planned#

Cloudflare plans to support all TypeScript features, including LSP, in a single package. VoidZero also says tsrs will become part of the Oxc toolchain.

Treat these as roadmap commitments. The announcements provided do not establish that full feature support or Oxc integration is currently available.

Before adopting it in an editor, check the specific features your team uses, such as completion, navigation, renaming, and incremental diagnostics. Keep validation with the existing compiler as a required step until you have confirmed sufficient tsrs compatibility with your codebase.

Next steps#

Before changing your build configuration, run a side-by-side comparison on a representative repository and record diagnostic differences, runtime, and peak memory usage.

Source: https://www.publickey1.jp/blog/26/cloudflaretypescriptrusttsrstypescript_7708lsptypescript.html

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