Blob and File (globals and node:buffer exports) compile to native
handles in the new scr_blob.c, following Node 24.22's
lib/internal/blob.js and file.js. A Blob is a window over a shared,
immutable byte store plus the byte length of each part. Sources (strings,
typed arrays, DataView, ArrayBuffer, Buffer, other Blobs, Set and Map)
convert as a Web IDL sequence, with each non-buffer part converted to a
string, before the options are read, and are copied when the Blob is
built. The constructors throw Node's Web IDL TypeErrors and its
ERR_INVALID_ARG_TYPE, ERR_INVALID_ARG_VALUE and ERR_MISSING_ARGS errors,
and read and convert their options in Node's order. The type is
lowercased, or cleared when it holds a character outside U+0020..U+007E.
endings: "native" rewrites CRLF, CR and LF to the platform's line break.
File takes its name with lone surrogates replaced and lastModified as a
number (Date.now() when absent).
slice() converts its offsets as a [Clamp] long long (rounded half to
even) and keeps the parts Node's data queue keeps. text(), bytes() and
arrayBuffer() settle on the same microtask turn as in Node, which depends
on the part count. util.inspect prints Node's `Blob { size, type }` and
`File { ..., name, lastModified }` forms, with `[Blob]` past the depth
limit. String() and toString() give the class tag, JSON.stringify gives
{}, and structuredClone returns a new Blob or File over the same bytes.
instanceof works for both spellings. stream(), textStream() and the
Object.prototype members other than toString() fail at compile time.
Non-array iterables other than Set and Map throw SC2020.
Three handle-table additions support this: a structuredClone hook, a
JSON `{}` flag, and a bracketed past-depth inspect flag. scr_blob.c is an
optional unit selected by dynAsync, because the dynamic dispatch path
boxes its reads as dyn promises through scr_async_dyn.c.
Corpus 5285-5290 and a node-types fixture check the behavior against
Node.
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.