This is very nice. I'm working on something similar as part of my build process so that I can more directly notice changes as they are made in markup, and catch

This is very nice. I'm working on something similar as part of my build process so that I can more directly notice changes as they are made in markup, and catch changes that I didn't expect. The issue I've hit, that you may want to consider, is a suppression list of sorts. The ability to silence diffs on things that look like dates for example would be rather valuable.