Shed Skin is an experimental compiler, that can translate pure, but implicitly statically typed Python programs into optimized C++. It can generate stand-alone programs or (simple, for now) extension modules, that can be imported and used from larger Python programs.

Besides the typing restriction, programs cannot freely use the Python standard library (although about 15 common modules, such as random and re, are currently supported). Also, not all Python features, such as nested functions and variable numbers of arguments, are supported.

For a set of 27 non-trivial test programs (at about 7,000 lines in total; see the ss-progs-0.0.27.tgz download), measurements show a typical speedup of 2-40 times over Psyco, and 2-220 times over CPython. Because Shed Skin is still in an early stage of development, however, many other programs will not compile out-of-the-box.