PyPy is a reimplementation of Python in Python, using advanced techniques to try to attain better performance than CPython. Many years of hard work have finally paid off. Our speed results often beat CPython, ranging from being slightly slower, to speedups of up to 2x on real application code, to speedups of up to 10x on small benchmarks. This post describes what we did on PyPy during the last year, leading up to those results. ...
source: PyPy 1.2 Released - Google Open Source Blog
