Cython Binding Generators Comparison¶

Several tools exist to parse header files and automatically produce Cython bindings.

Maintenance Status¶

Tool	Status	Most recent release
autowrap	✅ Active	v0.24.0 (2025)
python-autopxd2	✅ Active	v4.0.0 (2026)
cwrap	❌ Dead	8163ff2 (2019)
xdress	❌ Dead	eb7f0a0 (2014)
cython-codegen	❌ Dead	b1856d3 (2011)
fwrap	❌ Dead	f2e20eb (2010)
pxd-gcc-generation	❌ Dead	ba5c5ff (2012)

Automation Level¶

Step	autowrap	python-autopxd2
Input required	Hand-written .pxd	C/C++ header (unmodified)
Parse C/C++ header	❌ Manual	✅ Automatic
Generate .pxd declarations	❌ Manual	✅ Automatic
Generate .pyx wrappers	✅ Automatic	❌ Not generated
Generate cimport statements	❌ Manual	✅ Automatic
System include detection	❌ Manual -I flags	✅ Automatic
Recursive includes	N/A	✅ Automatic
Python↔C++ type conversion	✅ Automatic (runtime)	❌ Not applicable
Manual files to write	.pxd + setup.py	None

Workflow Comparison¶

python-autopxd2: Header → .pxd (fully automatic)¶

Use python-autopxd2 when:¶

You want to quickly generate .pxd files from existing headers
You don't want to write any Cython declarations by hand
You need to wrap a large C/C++ API with minimal effort
You want recursive processing of umbrella headers that include other headers

autopxd mylib.h mylib.pxd

Input: Unmodified C/C++ header Output: C/C++ <-> Cython interface (.pxd file) Manual work: Write Cython <-> Python interface (.pyx file)

autowrap: Hand-written .pxd → .pyx (semi-automatic)¶

Use autowrap when:¶

You need fine-grained control over Python-to-C++ type conversion
You want automatic .pyx generation with Python special methods
You need custom exception handling or operator overloads
You're willing to manually write .pxd declarations with annotations

autowrap --out mylib.pyx mylib.pxd

Input: C/C++ <-> Cython interface (.pxd file with special comment annotations) Output: Cython <-> Python interface (.pyx file ready to compile as an extension) Manual work: Write C/C++ <-> Cython interface (.pxd file)

Complementary usage:¶

Generate .pxd file with autopxd
```
autopxd mylib.h mylib.pxd
```
Manually annotate mylib.pxd for autowrap consumption
Generate .pyx file with autowrap
```
autowrap --out mylib.pyx mylib.pxd
```
Integrate .pyx file into your package build process

Language Support¶

Tool	C	C++	Fortran	Parser Backend
autowrap	✅	✅	❌	Cython parser (reads .pxd)
python-autopxd2	✅	✅	❌	libclang / tree-sitter
cwrap	✅	⚠️ Partial	❌	libclang / gcc_xml
xdress	✅	✅	❌	libclang / pycparser
cython-codegen	✅	❓	❌	gcc_xml
fwrap	❌	❌	✅	Custom Fortran parser
pxd-gcc-generation	✅	✅	❌	GCC plugin

Feature Comparison (Active Tools)¶

Feature	autowrap	python-autopxd2
Classes	✅	✅
Templates	✅	✅
Namespaces	✅	✅
Enums	✅	✅
Static methods	✅	✅
Macro extraction	❌	✅
Forward declarations	❌	✅
Exception conversion	✅	❌
Operator overloads	✅	✅
Python special methods	✅ (hash, etc.)	❌
Custom type converters	✅	❌
Manual code injection	✅	❌
Docker image	❌	✅

(Potential pipeline: header → autopxd2 → .pxd → add annotations → autowrap → .pyx)

Unmaintained Tools¶

cwrap¶

Original: https://github.com/enthought/cwrap (gcc_xml, 2011)
Fork: https://github.com/geggo/cwrap (libclang, ~2021)
C++ support noted as "rudimentary" with known issues

xdress¶

https://github.com/xdress/xdress Last release over a decade ago. The issue and pull request queues have gone unattended since.

cython-codegen (xml2cython.py)¶

https://github.com/cournape/cython-codegen Author states: "YOU SHOULD CONSIDER IT UNSUPPORTED" and recommends clang-based tools.

fwrap (Fortran only)¶

https://github.com/kwmsmith/fwrap Beta software from ~2011. Requires Python 2.5-2.6.

pxd-gcc-generation¶

https://github.com/robertwb/cython/tree/pxd-gcc-generation Philip Herron's 2012 GSoC project. Requires gcc-python-plugin.

h2pxd¶

Script by Evan Buswell. Status unknown. http://groups.google.com/group/cython-users/browse_thread/thread/67c3c4443a9c98ca