JavaScript, TypeScript and Python

The giz command also runs JavaScript, TypeScript and Python programs. They run on one VM (vm/): an interpreter and a JIT that both languages share. You need no Node.js and no Python install.

Run a program

giz run main.ts          # also .js, .mjs, .cjs and .py
giz main.py ARG...       # the short form

The first run builds the VM and caches it, as it caches any program. VM flags, such as --no-jit, go before the file. The flags are listed in the VM internals.

Build one executable

giz build main.ts -o app

The result is the VM with the files of your project: the folder of the nearest package.json at or above the script, else the script's folder. The first start unpacks the project into the cache and runs the entry there, so require, node_modules and file reads find the project as it was built.

JavaScript and TypeScript

• Modules resolve as in Node: package.json main, exports and imports, node_modules, .ts files, JSON modules, CommonJS and ES modules.
• eval and new Function work. A syntax error names the file and the line.
• Node's own lib/ runs on the VM. It starts at the first built-in require, or at the first use of a Node global (process, Buffer, URL, fetch), so a plain script does not pay for it.
• A .ts file runs with its types removed. Decorators follow TC39 2023.

Add an npm package to a project with its exact version. Installation scripts never run:

giz get . npm:semver@7

import semver from "semver";
console.log(semver.satisfies("1.2.3", "^1.0.0"));

Python

• sys.path is the script's folder, then PYTHONPATH, then the site-packages of $VIRTUAL_ENV or of the nearest .venv above the script, then the standard library of CPython 3.15 (fetched once into the cache).
• Python source (your program, the standard library and site-packages) runs on the VM. The hot C modules (sys, math, itertools, _json, _sre, _struct and others) are native in the VM.
• Any other C module, such as a wheel's .so or pydantic-core, runs in CPython 3.15 through a bridge. The VM loads it at the first such import.

Speed

Each program runs as a whole process, best of 5. Ratio is the reference time divided by the VM time: above 1, the VM is faster.

Each program and its number are in the VM internals.