Cython

What Cython is

Cython is a free static compiler for Python and the extended Cython language, used to build C extensions for Python. It converts source code into C or C++ that can be compiled as Python extension modules. Optional static type declarations can help generate more efficient C code from Python-like code, and Cython lets Python code call C or C++ through declared types. It also supports source-level debugging across Python, Cython, and C. The project describes uses such as wrapping external C libraries, embedding CPython in existing applications, and speeding up Python code with fast C modules. Cython can work with multidimensional NumPy arrays and integrate with existing low-level libraries and applications. Installation is available through pip, and some scientific Python distributions, including Anaconda and Sage, bundle it. A C compiler is required, with installation guidance for Linux, macOS, and Windows. The homepage describes generated-code compatibility with major C and C++ compilers for CPython 3.8 and later, while PyPy support is described as mostly usable. Limited API and free-threading support in Cython 3.1 are experimental. Cython is available under the Apache 2.0 License.

Who it suits

Cython suits Python developers who need to build C extensions, wrap external C libraries, or embed CPython in existing applications. It also fits those working with low-level libraries or multidimensional NumPy arrays.

Getting started

1. Install Cython with pip, or use a scientific Python distribution that bundles it, such as Anaconda or Sage.
2. Install a C compiler using the guidance for your operating system.
3. Use Cython's source-to-source conversion to generate C or C++ code for compilation as a Python extension module.

Verdict

Cython offers a route from Python-like source to compiled extension modules, with options for static types, C/C++ interoperation, and debugging. Users need a C compiler, and the listed Limited API and free-threading support remains experimental.