• CPython 2.5. Works fine. Can be sped up with Cython or Psyco (x86 only).
  • CPython 2.6. Works fine. Can be sped up with Cython or Psyco (x86 only).
  • CPython 2.7. Works fine. Can be sped up with Cython.

  • CPython 3.0. Works fine. Can be sped up with Cython.
  • CPython 3.1. Works fine. Can be sped up with Cython.
  • CPython 3.2. Works fine. Can be sped up with Cython.

  • Pypy 1.5. Usually works, but sometimes leaks memory.
  • Pypy 1.6. Contained an os.stat()-related bug that causes tracebacks.
  • Pypy 1.7. Works well.
  • Pypy 1.8. Works well. Very fast - faster than the Cython's (!).

  • Jython 2.5.2. Does not work.
  • Jython 2.5.3 -r 7288 no longer works; it does not update timestamps correctly.
  • Jython 2.5.3b1 mostly works, but skips backing up device files. Should be able to restore device files though. It also cannot detect symlink races during backups, which has security implications.

  • Cygwin CPython 2.x. Works fine.

    Be sure to check out the performance comparison too.