When a build breaks, or starts acting differently, you want to know "what changed?". Sometimes this is right away, other times you only start investigating a change days or weeks later. Regardless, having a definitive way to know what changed at the time, helps figure it out and also helps avoid wasting a lot of time chasing wrong leads.Most of the relevant changes would be in the source repo, where you can easily track them. Some other changes may be in the CircleCI infrastructure. For CircleCI Server, that's up to your local IT department to track and communicate about. But one siginifcant portion of the build environment is project settings, especially environment variables: - Many builds depend on environment variable values, and can easily change behavior or break when those are changed. - Environment variables are opaque, you can't even see what's in them or recognize that the values are different. - There is no change history or log of any sort.Please remedy the last point: Allow us to see the time+date and username for every addition or removal of an environment variable. (I believe it's not possible to just change a value, you have to remove and then add, but if I'm wrong and it is possible, that should be in the log as well)

CCI-I-1566