Install

fiscalclock is published as three packages built from one Rust core: a Python package, an npm package and a Rust crate. The Python and npm packages call the core and return its JSON unchanged, so the same definition and inputs give the same results in every language (API spec).

Python

pip install fiscalclock

JavaScript

npm install fiscalclock

Rust

cargo add fiscalclock

Supported versions

As of 2 Nov 2026, the latest release of all three packages is 0.1.0, published on 31 Oct 2026 (changelog). The definition format and the API are version 1 drafts and may change before 1.0.

Package	Supports	Source
Python	CPython 3.10 and later, with one stable-ABI wheel per platform, and free-threaded CPython 3.14. Wheels for Linux (x86-64 and Arm64, including musl-based distributions), macOS (x86-64 and Arm64) and Windows (x86-64).	requires-python in pyproject.toml; the files of fiscalclock 0.1.0 on PyPI
JavaScript	Node.js 22 and later, and browsers, through WebAssembly. The package is an ES module with TypeScript types.	engines in package.json; the npm package README
Rust	Rust 1.85 and later. The crate is no_std with alloc.	rust-version in Cargo.toml; the crate README

In Node.js the npm package loads its WebAssembly module from disk when it is imported. In other environments its entry point fetches the module relative to its own URL with top-level await (npm package README).

Every code example on this site is a file in the website/examples/ folder of the repository, and npm run test:examples in website/ runs each one against version 0.1.0 of the package for its language and checks that it prints the output shown.

Check a download

Every release file has a build provenance attestation. The README explains how to check a downloaded wheel, npm tarball or crate with gh attestation verify.

Next, the quick start writes a definition and asks it about a date.