code-wizards.com project:
  libfaketime (FakeTime Preload Library) - report faked system time to programs without having to change the system-wide time

Current version: 0.9.6, released June 2014
Download libfaketime-0.9.6.tar.gz

Visit the GitHub project page: https://github.com/wolfcw/libfaketime
Changelog
Read the documentation (Linux + OSX): https://github.com/wolfcw/libfaketime/blob/master/README
Information on using libfaketime specifically for OSX: https://github.com/wolfcw/libfaketime/blob/master/README.OSX

For bug reports, suggestions, feedback please use the Github issue tracker for libfaketime.
If you want to contribute code, please send git pull requests via Github.