The runtime vendored zlib 1.3.1 and archived it at -Os, and host C-lane builds linked the system libz, so deflate, raw deflate and gzip output differed from Node's at every level. The vendored copy is now Node v24.22.0's deps/zlib (Chromium's zlib, 1.3.2.1-motley-285e94b), built at -O3 with the units and defines Node's zlib.gyp selects per target: the SSSE3 Adler-32 and SSE2 inflate and slide-hash code on x86-64, the NEON and ARMv8 CRC-32 code on arm64, and the portable code on wasm32. The SIMD units check the CPU at run time and give the same output, so compressed bytes match Node's on every target. zlibInputs (runtime-pack-common/scripts/zlib-inputs.mjs for the runtime packs, vendor-inputs.ts for Zig cross builds and the sanitized runtime) holds the per-target table, and a unit test keeps the two identical. Every C-lane driver now links the vendored objects instead of -lz. Chromium's BSD license ships beside zlib's in the runtime packs. Corpus 8405 compares compressed bytes with Node across levels, strategies, memLevel, windowBits, dictionaries and flushing streams; 8406 covers chunked inflation with small input pieces and output chunks.
scriptc
scriptc compiles TypeScript and JavaScript to native executables and WebAssembly. It uses the types checked by the TypeScript compiler to generate machine code, and the output runs without Node.js installed. npm packages your program imports compile along with it. Code scriptc can't compile is reported at build time with a diagnostic and, where available, a rewrite hint.
scriptc is experimental and supports a subset of JavaScript, TypeScript, and Node.js APIs. Run scriptc coverage on an existing program to see how much of it compiles, and see the limitations and Node.js compatibility reference for details.
Installation
Install with Node.js 24 or later and npm:
$ npm install -g scriptc
The installed compiler runs natively on macOS, Linux, and Windows. Node.js is needed only to install it and to run WASI modules with scriptc run. Standalone compiler archives are also available from GitHub Releases.
Building executables requires a linker and the platform SDK or sysroot. See the quickstart for prerequisites and platform support for host requirements, cross-compilation, and WebAssembly.
Build a program
Create hello.ts:
const who = process.argv.length > 2 ? process.argv[2] : "world";
console.log(`hello, ${who}`);
scriptc run compiles the file and runs the result:
$ scriptc run hello.ts
hello, world
scriptc build writes an executable:
$ scriptc build hello.ts -o hello >/dev/null
$ ./hello scriptc
hello, scriptc
These examples use POSIX shell syntax. On Windows, build hello.exe and run it with .\hello.exe.
Use scriptc coverage hello.ts to check what compiles before you build. See coverage reports for details.
Use Node APIs
Supported Node APIs compile to the native runtime. For example, server.ts:
import { createServer } from "node:http";
const server = createServer((req, res) => {
res.setHeader("content-type", "application/json");
res.end(JSON.stringify({ path: req.url }));
});
server.listen(8080, () => {
console.log("listening on http://localhost:8080");
});
$ scriptc build server.ts -o server >/dev/null
$ ./server
listening on http://localhost:8080
Use npm packages
npm packages compile into the executable with your code, so it doesn't read node_modules at runtime.
Create cli.ts:
import pc from "picocolors";
console.log(pc.green("hello from scriptc"));
$ npm install picocolors
$ scriptc build cli.ts -o cli >/dev/null
$ ./cli
hello from scriptc
Package support is partial. See npm dependencies for which packages compile and how to check them.
Documentation
- Introduction: what scriptc is and what you can build.
- Quickstart: installation and your first executable.
- Coverage reports: check whether an existing program compiles.
- Platform support: cross-compilation and WebAssembly.
- CLI reference: commands, options, and output formats.
- Native program objects: use compiler output in external builds.
- Native FFI: call C ABI functions from compiled programs.
- WebAssembly modules: build and embed WASI modules.
- Examples: programs and integration examples in this repository.
Contributing
See CONTRIBUTING.md for source setup, testing, native artifact builds, and docs development.