Woxi 0.3 runs Mathematica notebooks on an open-source Rust engine

Why it matters

Woxi is testing whether Wolfram Language code can become portable infrastructure. Browser and embedded runtimes matter only if compatibility survives real notebooks, graphics and symbolic workloads.

Adrian Sieber (@AdrianSieber) released Woxi 0.3.0 on August 6th, shifting his open-source Wolfram Language reimplementation from accumulating functions to executing complete Mathematica notebooks. The release lets its native Woxi Studio editor open and run a selection of interactive Wolfram Demonstrations end to end, while adding prebuilt Windows binaries alongside Linux and macOS builds. (github.com)

Sieber is a Frankfurt-based software developer and the CEO of Airsequel, a hosted SQLite service that generates GraphQL APIs, spreadsheet interfaces and other database tools. His personal project history includes a command-line task manager, a plain-text accounting tool and Feram, a code-analysis service he co-founded in 2017. Woxi extends that pattern into a much larger target: a compatible, independently implemented engine for a proprietary language developed since 1988. (github.com)

Sieber's bet centers on distribution. The Woxi repository packages the interpreter as a command-line tool, Jupyter kernel, Python package, npm package and WebAssembly module. The same Rust engine can therefore run inside a shell script, notebook, Python process, Node application or browser. Woxi's browser playground executes locally, according to its documentation, without sending computations to a remote server. (woxi.ad-si.com)

The Python package reached version 0.3.0 on August 7th with prebuilt wheels for Windows, macOS and Linux. It exposes symbolic evaluation, persistent session state and SVG graphics through Python calls. Woxi is licensed under AGPL-3.0-or-later, a choice that keeps modifications to deployed versions subject to the license's source-sharing requirements. (pypi.org)

From function count to notebook compatibility

Version 0.3.0 concentrates on behavior that developers encounter when opening real .nb files. Woxi Studio can reconstruct stored Manipulate widgets, interpret typeset notebook input as executable code and render interactive controls including locators, buttons, menus and animations. Sieber used demonstrations covering Kepler's second law, parabolic mirrors, Doyle spirals and damped pendulums as end-to-end tests. (github.com)

The graphics work reaches beyond basic plots. The release added or corrected error bars, fills, plot markers, three-dimensional surfaces, polygon holes, SVG font embedding and Wolfram-style automatic ticks. Its calculus and algebra additions include further symbolic integrals, differential-equation cases, constrained optimization and equation solving. The release notes say several rounds of differential fuzzing against wolframscript exposed silent differences in arithmetic, expression ordering and simplification. Those comparisons are central to Woxi's approach because a familiar function name has limited value when evaluation or output diverges from existing Wolfram code. (github.com)

Woxi also makes several deliberate departures. Its comparison with Mathematica says the command-line program can directly evaluate input cells from .nb notebooks, which WolframScript does not support. Woxi Studio automatically executes preceding cells rather than permitting arbitrary out-of-order evaluation, an attempt to prevent notebook results from depending on hidden kernel state. The editor also omits Mathematica's % shorthand for the previous result. (woxi.ad-si.com)

The compatibility gap remains large

The Mathematica comparison doubles as a boundary around the current product. Woxi's documentation lists the Wolfram Knowledgebase, machine learning, neural networks, finite-element methods, chemistry, video computation, signal processing and several other areas as mostly unimplemented. Features added in Mathematica 15.0, including GPU kernels, WebSocket connectivity, a rebuilt time-series engine and Wolfram's agent tooling, also remain outside Woxi's coverage. (woxi.ad-si.com)

The project says it fully supports Mathematica 1.0's original 554 built-in functions and symbolic core. That historical baseline is useful, but current Mathematica spans decades of accumulated domain libraries, data systems and notebook behavior. Woxi's practical test is whether it can support a narrower set of reproducible scripts and notebooks well enough that developers can embed them without running a Wolfram kernel. (woxi.ad-si.com)

Woxi is also entering an established open-source effort rather than creating the first alternative Wolfram engine. Mathics3, a Python implementation whose development history dates to 2011, describes itself as an open-source Mathematica kernel and has roughly 1,200 GitHub stars. Woxi had about 750 stars as of August 12th. Sieber's differentiation rests on Rust, portable binaries, WebAssembly embedding and one engine spanning the command line, browser and native notebook editor. (github.com)

The 0.3.0 release gives that strategy a concrete proving ground. Complete notebooks expose incompatibilities that isolated function tests miss: evaluation order, typesetting, interactive state, graphics layout and error behavior all have to agree closely enough for existing work to run. Woxi has started testing against that harder standard, while its own compatibility table makes clear how much of Mathematica remains beyond reach.