[cctbxbb] How to hack at the autobuild?

Hi, I have found a few issues with auto build on recent versions of Fedora. I need to edit files in libtbx/autobuild to fix them but then I want to test that running bootstrap works. But then bootstrap.py always pull from github. I don’t want to push my changes to github until it’s solid though. How do you guys approach that? Best wishes, Luc