Have you used Phabriactor? This sounds an awful lot like a Diff in its terms. "master" is a linear sequence of Diffs being landed, with Diff number in the commi

Have you used Phabriactor? This sounds an awful lot like a Diff in its terms. "master" is a linear sequence of Diffs being landed, with Diff number in the commit message. You can paste that diff number in the web UI and see the individual commits that were part of it.