modelx-cython: Cythonize modelx models

modelx-cython is a Python package that translates modelx models exported as pure-Python packages into Cython packages and compiles them into native extension modules, so that the models run faster and use less memory.

Warning

modelx-cython is currently highly experimental and is released only for early adopters with advanced software engineering skills to explore its capability.

modelx-cython installs the mx2cy command. Given a model exported by modelx’s Model.export method, mx2cy runs a user-supplied sample script to observe the types that flow through the model, rewrites the model’s source code with Cython type annotations, and compiles the result into a new package that can be imported in place of the original.

$ mx2cy Model_nomx

Documentation contents

• Installation
  • Installing modelx-cython
  • Requirements
  • C compiler
• Tutorial
  • Step 1: Export the model from modelx
  • Step 2: Write a sample script
  • Step 3: Write a spec file (optional)
  • Step 4: Run mx2cy
  • Step 5: Use the compiled model
• Command reference
  • Synopsis
  • Positional arguments
  • Options
  • Exit status
  • Files
• Spec file reference
  • File format
  • Keys
  • Deprecated keys
  • Return types of array-valued cells
• Free-threaded Python
  • Exporting a model for threads
  • Running the compiled model from threads
  • What the compiled model guarantees
  • How locked Spaces are translated
• Implementation details
  • Architecture
  • Module reference
• Release Notes
  • v0.1.0 (5 September 2026)
  • Earlier releases

See also

• modelx GitHub Repository

• modelx Documentation

• modelx Blog

License

Copyright 2023-2026, Fumito Hamamura

modelx-cython is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License v3 (LGPLv3).

Portions of modelx-cython are derived from MonkeyType, which is distributed under a BSD-style license.