PyPy 5.1 发布了，PyPy是Python开发者为了更好的Hack Python创建的项目。此外，PyPy比CPython是更加灵活，易于使用和试验，以制定具体的功能在不同情况的实现方法，可以很容易实施。 该项目的目标是，让PyPy比C实现的Python更为容易的适应各个项目和方便裁剪。
该版本支持平台：
x86 machines on most common operating systems (Linux 32/64, Mac OS X 64, Windows 32, OpenBSD, FreeBSD),
newer ARM hardware (ARMv6 or ARMv7, with VFPv3) running Linux,
big- and little-endian variants of PPC64 running Linux,
s390x running Linux
一些提高：
A new jit backend for the IBM s390x, which was a large effort over the past few months.
Add better support for PyUnicodeObject in the C-API compatibility layer
Support GNU/kFreeBSD Debian ports in vmprof
Add __pypy__._promote
Make attrgetter a single type for CPython compatibility
更多详细信息，可以在这里查看。