Compatibility: PyPy is highly compatible with existing python code. It supports cffi, cppyy, and can run popular python libraries like twisted, and django. It can also run NumPy, Scikit-learn and …

Source 3.11 Source (tar.bz2); 3.11 Source (zip). 2.7 Source (tar.bz2); 2.7 Source (zip). More information Visit the more information page for other platforms, information about running …

Unlike other sandboxing approaches for Python, PyPy's does not try to limit language features considered "unsafe". Instead we replace all calls to external libraries (C or platform) with a …

Jan 12, 2026 · Welcome to the documentation for PyPy, a fast, compliant alternative implementation of the Python language. If you want to find out more about what PyPy is, have …

Jan 12, 2026 · What is PyPy? Historically, PyPy has been used to mean two things. The first is the RPython translation toolchain for generating interpreters for dynamic programming …

Jan 12, 2026 · What is PyPy? PyPy is a reimplementation of Python in Python, using the RPython translation toolchain. PyPy tries to find new answers about ease of creation, flexibility, …

Dec 24, 2025 · The PyPy team is proud to release version 7.3.20 of PyPy after the previous release on Feb 26, 2025. The release fixes some subtle bugs in ctypes and OrderedDict and …

Jan 12, 2026 · The quickest way to start using PyPy is to download a prebuilt binary for your OS and architecture. You may be able to use either use the most recent release or one of our …

Feb 26, 2025 · The PyPy team is proud to release version 7.3.19 of PyPy. This is primarily a bug-fix release fixing JIT-related problems and follows quickly on the heels of the previous release …

The main difference in pure-python code that is not going to be fixed is that PyPy does not support refcounting semantics for "automatically" releasing state when an object's __del__ is …