Ross ROSS = Recommend OSS · open-source software intelligence for agents

marcj/TypeRunner

High-performance TypeScript compiler observed · 2026-08-28

github.com/marcj/TypeRunner · C++ · MIT (permissive) observed · 2026-08-28

Health v2 · maintenance only

37/100

  • Activity 10
  • Release rhythm 35
  • Longevity 100

Flags: no_releases

How is this computed?

round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10) — computed 2026-09-02. Adoption (stars, forks) is never an input.

  • gap_med: n/a
  • age_days: 1492
  • days_rel: n/a
  • days_push: 545
  • n_releases_24m: 0

Full methodology

Adoption not part of the score

2657 stars · 39 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-30, confidence not recorded

TypeRunner is a high-performance TypeScript type checker written in C++ that compiles TypeScript to bytecode and executes it in a custom virtual machine, claiming hundred- to thousand-fold speedups over tsc. It is currently a proof of concept (~30k LoC) aiming to also provide a language server, native library for other languages, and optional transpiling.

Use cases

  • type check typescript code much faster than tsc
  • use typescript type information from other languages without a js engine
  • replace schema with typescript types as a dsl
  • use typescript types for orm definitions or protocol buffer schemas
  • interactively debug typescript types

When to avoid

  • you need a drop-in replacement for the official tsc compiler
  • your code relies on JSDoc types or many legacy compiler options
  • you need a production-ready, fully featured type checker today

Facets

library · maturity experimental

compiler type-system cli parser programming-languages compilers developer-tools performance cpp cross-platform cli typescript type-checking bytecode virtual-machine proof-of-concept

1 source

Member repositories

RepositoryRoleHealth v2
marcj/TypeRunnermain37

For agents

markdown · JSON · MCP: product_card(name="marcj/TypeRunner")

Data as of 2026-08-30T08:39:29.467469+00:00 · Report a problem