A Linux executable link runs `clang -fuse-ld=lld ...`, and the driver only starts ld.lld with a job it derives from its arguments, its environment and the installed toolchain. Starting the driver costs about 10 ms of a small program's 29 ms link. LinkerJobs (native/linker-job.ts) records that job in the native cache, with the link's own inputs and output as positions. A traced link (the Linux executable cache's `-v -Wl,-t` link) records it from the job line the driver prints with -v; a link the executable cache does not trace lists it with -v -### first. The entry also keeps the identities of the files and directories the job and the driver's -v lines name (ld.lld, startup objects, library directories, the GCC installation, the driver's directory): the set the Linux executable cache records from its traced link. It is keyed by the driver's identity, the link's arguments, the toolchain environment, PATH and the working directory. A later link with the same key whose recorded paths still have those identities runs ld.lld with the job directly, and the executable cache traces it with the job's -t output and the recorded identities. Every other link runs through the driver as before: cross-target links, links without lld, a driver that is not clang, SCRIPTC_LINKER, sanitizer links, a toolchain environment that names mutable inputs, a listing without exactly one ld.lld job naming each of the link's paths once, a recorded path whose identity changed, and a job that fails (the driver then reports the error). The linker gets the same arguments, so the executables are identical.
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.