Tsc-ts: TypeScript written in TypeScript

An experimental TypeScript port of the TypeScript 7.0.2 compiler (TypeScript-Go, or tsgo), compiled to native code with scriptc.

npm install -D tsc-ts npx tsc-ts -p tsconfig.json

The tsc-ts package runs a native executable from a per-platform optional dependency (@tsc-ts/darwin-arm64, @tsc-ts/linux-x64-gnu, …). See packages/tsc-ts.

See CHANGELOG.md for release notes and GitHub Releases for package archives.

To build the packages for the current platform:

npm run pack:npm -w tsc-ts # packages/tsc-ts/dist/npm/*.tgz npm run pack:npm -w tsc-ts -- --check # also install the tarballs and compile a project

-- --binary dist/tsc packs an existing native build, relative to packages/tsc-ts, instead of building one.

Package Description

packages/tsc-ts The compiler, written in TypeScript, with the tsc-ts command line and --api server.

packages/tsgo Reference builds of tsgo (its command line and per-stage drivers) that the tests compare against.

Tasks run with Turborepo.

apps/web contains the tsc-ts compiler guides.

npm run dev:web npm run build:web

Requirements

Node.js 24+ and npm

Go 1.26

A scriptc host: macOS, Linux, or Windows, with clang available for linking

Build

npm ci npm run fetch:upstream # clone tsgo at the pinned commit npm run build # the Node build of tsc-ts (packages/tsc-ts/dist) and the documentation site npm run build:oracle # tsgo reference builds in packages/tsgo/dist

package.json pins scriptc 0.3.5, with its @scriptc/threads package. The build fails with any other version.

packages/tsc-ts/src/compiler is the compiler, ported from tsgo 7.0.2 as idiomatic TypeScript. Each part is compared with tsgo on TypeScript's test corpus (about 12,500 files, 17,000 units after splitting multi-file cases):

The corpus scripts are in packages/tsc-ts/scripts (*-corpus.mjs).

tsc-ts --api serves the same API as TypeScript 7.0.2's tsc --api, over stdin and stdout, so tools that drive tsc --api (such as scriptc) can run tsc-ts instead.

npm run build -w tsc-ts node packages/tsc-ts/dist/tsc-ts/src/main.js --api --cwd path/to/project

Native builds read lib files from the executable's directory, or from TSC_TS_LIB_DIR:

npm run build:native -w tsc-ts # packages/tsc-ts/dist/tsc npm run build:native:dev -w tsc-ts # unoptimized, faster to build TSC_TS_LIB_DIR=upstream/typescript-go/internal/bundled/libs packages/tsc-ts/dist/tsc -p path/to/project

TSC_TS_BIN=packages/tsc-ts/dist/tsc runs the tsc-ts tests that take a native build against it.

The server is checked against tsc --api 7.0.2 response by response, and scriptc builds the same programs with either. It runs on the tsc-ts compiler, natively or under Node.

Language service methods are supported: getCompletionsAtPosition, getJsDocTags, getDocumentationComment, getReferencesToSymbolInFile, getReferencedSymbolsForNode and getSignatureUsages. Like tsc --api, completions that need auto imports (global identifiers, import statements, exhaustive switch cases) report completion list needs auto imports. The profiling methods (startCPUProfile, stopCPUProfile, saveHeapProfile) are not supported.

npm test # compare tsc-ts with tsgo npm run bench -w tsc-ts # time tsc-ts against tsgo and TypeScript's JavaScript compiler npm run lint # oxlint npm run format # oxfmt

License

Apache-2.0. See THIRD_PARTY_NOTICES.md for TypeScript-Go and other third-party notices.