I welcome any and all types of contributions, even if it's just fixing a single small spelling mistake.
If you are making code changes I only ask that you do one thing before making a pull request. Make sure that:
Passes without any issues, if you do a major overhaul of any code I'd also appreciate if you wrote tests for it too! Timestrap is not a project that shoots for 100% test coverage because I consider that a waste of time, I just like to make sure major parts of the code base don't break. (That's not to say I wouldn't like to have 100% test coverage some day...)