Delta Debugging is a fantastic tool which will take a test case which crashes a program and reduce it until you are left with the smallest file which still causes the crash. It is quite efficient at doing this and has a lot of academic research backing it up. More importantly, it is very practical in the real world at helping triage crashes.

For more info, check out their site: https://www.st.cs.uni-saarland.de/dd/

This fork of DD is compatible with both Python 2 and 3 (original was written for Python 2 and did not work in 3). We also plan on making some scripts to improve usability and reduce the amout of custom python code that needs to be written and hopefully eliminate the need to write any custom code in most cases.