hpyproject/hpy

Health v2 · maintenance only

Adoption not part of the score

1140 stars · 51 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-30, confidence not recorded

HPy is a new C API and ABI specification for extending Python that is implementation-agnostic, working across CPython, PyPy, and GraalPy. It offers zero-overhead on CPython, universal binaries, a debug mode for detecting memory leaks and API misuse, and an incremental migration path from the legacy C API.

Use cases

• write Python C extensions that run on CPython, PyPy, and GraalPy
• port an existing CPython C API extension to a portable API
• detect forgotten Py_INCREF/Py_DECREF memory leaks in C extensions
• build universal binaries that stay compatible across Python versions
• speed up C extensions on alternative Python implementations like PyPy
• experiment with CPython internals like removing the GIL or using a GC

When to choose

• you maintain a C extension and want compatibility with PyPy or GraalPy
• you want runtime debugging of reference-counting bugs in C extensions
• you want binary stability across CPython versions without recompiling
• you are building new C extensions and want a cleaner, more consistent API

When to avoid

• you only target CPython and are happy with the standard C API
• you depend on C API features not yet covered by HPy
• you need a fully stable, long-term-supported ABI today since HPy is still approaching its first stable release

Facets

library · maturity active

programming-language sdk developer-tools programming-languages developer-tools performance python cpp cross-platform c-api python-extensions cpython pypy graalpy abi debug-mode

Member repositories

For agents

markdown · JSON · MCP: product_card(name="hpyproject/hpy")