Chris Tate
f1e6addc81
An encoded message allocated a node array (four nodes of 184 bytes to
start, trimmed when encoding ended), a property array per object, a copy
of every key and string, and the encoder's visit, identity and stack
arrays. A port that queues many messages kept all of it until delivery:
a {id, name} object took 15 allocations and 1.9 KB, and most of
postMessage's time went into page faults on that memory.
- The encoder builds nodes, properties and visits in arrays that start on
the stack (8 entries), keeps borrowed references to keys and strings,
and copies the result into one allocation: the header, the nodes, the
properties grouped by node, the typed records and the text. A node is
40 bytes; the per-kind fields share a union. ArrayBuffer contents stay
in their own allocation.
- Decoding uses stack arrays for messages of up to 8 nodes and allocates
the storage table only when the message has ArrayBuffer contents.
- Freeing a message frees the block, and walks the nodes only when the
message holds ports, native handles or ArrayBuffer contents.
- The publication check reads the root before collecting the graph, so
a message whose root is not frozen allocates nothing for it.
The same object message now takes 4 allocations and 302 bytes, and a
number 3 allocations and 129 bytes. bench/channel-messages runs in 161 ms
instead of 250 ms (Node: 340 ms), with a peak RSS of 45 MB instead of
115 MB, and bench/worker-messages in 273 ms instead of 348 ms.
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.