PyPy 2.3.1 - Terrestrial Arthropod Trap Revisited

We’re pleased to announce PyPy 2.3.1, a feature-and-bugfix improvement over our recent release last month.

This release contains several bugfixes and enhancements.

You can download the PyPy 2.3.1 release here:

We would like to thank our donors for the continued support of the PyPy project, and for those who donate to our three sub-projects. We’ve shown quite a bit of progress but we’re slowly running out of funds. Please consider donating more, or even better convince your employer to donate, so we can finish those projects! The three sub-projects are:

  • STM (software transactional memory): a preview will be released very soon, once we fix a few bugs
  • NumPy which requires installation of our fork of upstream numpy, available on bitbucket

What is PyPy?

PyPy is a very compliant Python interpreter, almost a drop-in replacement for CPython 2.7. It’s fast (pypy 2.3 and cpython 2.7.x performance comparison; note that cpython’s speed has not changed since 2.7.2) due to its integrated tracing JIT compiler.

This release supports x86 machines running Linux 32/64, Mac OS X 64, Windows, and OpenBSD, as well as newer ARM hardware (ARMv6 or ARMv7, with VFPv3) running Linux.

While we support 32 bit python on Windows, work on the native Windows 64 bit python is still stalling, we would welcome a volunteer to handle that.


Issues with the 2.3 release were resolved after being reported by users to our new issue tracker at or on IRC at #pypy. Here is a summary of the user-facing changes; for more information see whats-new:

  • The built-in struct module was renamed to _struct, solving issues with IDLE and other modules.
  • Support for compilation with gcc-4.9
  • A rewrite of which produces our downloadable packages to modernize command line argument handling and to document third-party contributions in our LICENSE file
  • A CFFI-based version of the gdbm module is now included in our downloads
  • Many issues were resolved since the 2.3 release on May 8

Please try it out and let us know what you think. We especially welcome success stories, we know you are using PyPy, please tell us about it!


The PyPy Team