pyo3 vs pythonnet
Rust-Python and Python-.NET interoperability compared
pyo3 connects Rust and Python, supporting native Python extensions and Python embedding in Rust applications. pythonnet connects Python and .NET, letting Python use CLR libraries and .NET applications embed Python. The choice depends on whether Rust or .NET is the other ecosystem you need to integrate.
pyo3: Connect Rust Code with Python
PyO3 lets Rust code work with Python in both directions: build native Python extension modules or embed Python in Rust programs. It suits developers who want Rust functionality in Python packages or Python libraries available to Rust applications.
pythonnet: Connect Python with the .NET Runtime
Python.NET lets Python programs use .NET libraries and lets .NET applications embed Python. It suits developers integrating the two ecosystems, with runtime setup and Python’s thread and object-handling rules to account for.
| pyo3 | pythonnet | |
|---|---|---|
| Language | Rust | C# |
| License | Apache-2.0 | MIT |
| Stars | 16.2k | 5.5k |
| Forks | 1k | 780 |
| Last analyzed | Oct 7, 2026 | Oct 3, 2026 |
Key differences
- pyo3 is a Rust library for exposing Rust functions and types to Python or calling Python from Rust; pythonnet bridges Python with the .NET CLR in both directions.
- pyo3 supports CPython 3.9 or newer, PyPy 7.3 with Python 3.11 or newer, and GraalPy 25.0 or newer with Python 3.12 or newer; pythonnet requires compatible Python and CLR runtimes and documents Mono, .NET Framework, and CoreCLR setup.
- pyo3 is licensed under Apache-2.0, while pythonnet is licensed under MIT.
- The provided project facts list 16.2k stars and 1k forks for pyo3, and 5.5k stars and 780 forks for pythonnet.
- pyo3 requires Rust 1.85 or newer and notes that embedding needs a Python installation with a shared library; pythonnet embedding requires Python shared-library configuration and calls made while holding the GIL.
Choose pyo3 if you…
- need Rust code to expose native extension modules to Python.
- want a Rust application to call Python code or libraries.
- are working with one of pyo3's supported Python runtimes and can use Rust 1.85 or newer.
Choose pythonnet if you…
- need Python code to use .NET assemblies, namespaces, or APIs.
- want a .NET application to embed Python scripts or libraries.
- can configure compatible Python and CLR runtimes and handle embedding requirements such as the GIL.
Compare the numbers side by side, or add more projects
This comparison is generated with AI from the OSRepos analyses of both projects. Always check each project's repository and documentation before choosing.