node:test changes, matching Node 24.22: - t.assert.snapshot(value[, options]) serializes the value with Node's default serializer, JSON.stringify(value, null, 2), or with an options.serializers array literal applied in order, and compares it with assert.strictEqual against the snapshot stored under "<test full name> <n>" in "<entry file>.snapshot". - t.assert.fileSnapshot(value, path[, options]) compares the serialized value with the contents of path. - Snapshot files are read in the form Node writes them, exports[`key`] = `value`; statements, with template escapes and CRLF line endings cooked as in a template literal. - Missing snapshots, unreadable snapshot files and throwing serializers throw Node's ERR_INVALID_STATE errors, with Node's messages. - Running the binary with Node's --test-update-snapshots flag as its first argument records the values and writes the snapshot files after the last test, keys sorted as Node sorts them. The flag is kept out of process.argv and appears in process.execArgv, which is otherwise []. - Snapshot assertions count toward the test's plan. The snapshot fixture compares the reporter output with Node, plain and with SCRIPTC_SAN=1, against a snapshot file Node wrote. The update-mode harness test runs Node and the binary with --test-update-snapshots and compares the files they write. The node:test normalization also drops the "... N lines matching cause stack trace ..." line Node prints for an error cause, with the stack frames it summarizes.
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.