CYTHONIZE(1)

💖 CYTHONIZE(1) 💖

okay bestie, welcome to cythonize from the User Commands corner of the manual, and no cap this one is a whole vibe 💅

---

✨ NAME ✨

cythonize — compile Cython code (.pyx) into C so you can build a Python extension 🦋

---

🌸 DESCRIPTION 🌸

so the usage is literally this, copy it exactly pls:

usage: cythonize [-h] [-X NAME=VALUE,...] [-E NAME=VALUE,...] [-s
       NAME=VALUE]

       [-2] [-3] [--3str] [-+] [-a] [--annotate-fullc] [-x PATTERN] [-b]
       [-i] [--timeit CODESTRING] [--setup CODESTRING] [-j N] [-f] [-q]
       [--lenient] [-k] [--no-docstrings] [-M] [sources ...]

like, that's the whole shape of it, and it's giving "I have opinions and I will share them" 🌈

🎀 positional arguments: 🎀

• sources — the files you're feeding in, your main characters fr

💜 options: 💜

• -h, --help — show this help message and exit, the classic escape hatch 🫶
• -X, --directive NAME=VALUE,... — set a compiler directive
• -E, --compile-time-env NAME=VALUE,... — set a compile time environment variable
• -s, --option NAME=VALUE — set a cythonize option
• -2 — use Python 2 syntax mode by default
• -3 — use Python 3 syntax mode by default
• --3str — use Python 3 syntax mode by default (deprecated alias for -3) ⚠️ it's deprecated, so like, it still works but it's giving "old news"
• -+, --cplus — Compile as C++ rather than C 🔥
• -a, --annotate — Produce a colorized HTML version of the source. ✨ aesthetic AND useful
• --annotate-fullc — Produce a colorized HTML version of the source which includes entire generated C/C++-code. like the annotated version but extra, it shows the whole generated C/C++-code too 👑
• -x, --exclude PATTERN — exclude certain file patterns from the compilation 🙈
• -b, --build — build extension modules using distutils/setuptools
• -i, --inplace — build extension modules in place using distutils/setuptools (implies -b)
• --timeit CODESTRING — build in place, then compile+run CODESTRING as benchmark in first module's namespace (implies -i) ⏱️
• --setup CODESTRING — use CODESTRING as pre-benchmark setup code for --bench
• -j, --parallel N — run builds in N parallel jobs (default: 6) — six at once, we love a multitasking queen 💅
• -f, --force — force recompilation
• -q, --quiet — be less verbose during compilation 🤫
• --lenient — increase Python compatibility by ignoring some compile time errors
• -k, --keep-going — compile as much as possible, ignore compilation failures, she does not give up 💪
• --no-docstrings — strip docstrings
• -M, --depfile — produce depfiles for the sources

🌈 Environment variables: 🌈

• CYTHON_FORCE_REGEN: if set to 1, forces cythonize to regenerate the output files regardless

of modification times and changes.

• CYTHON_CACHE_DIR: the base directory containing Cython's caches. Environment variables accepted by setuptools are supported to configure the C compiler and build: https://setuptools.pypa.io/en/latest/userguide/ext_modules.html#compiler-and-linker-options

bestie reminder: those two Cython env vars and the setuptools ones are all doing real work behind the scenes, so don't just set them and forget, iykyk 🧚

---

and that's the whole page, fr fr 🍓 this was Cython 3.1.6, from March 2026 — ty for reading, mwah 💖🎀