How can we know the difference between nightly builds?

We have a list of nightly builds of MS4 that is being renewed daily or even several times a day, but there is no way of knowing what exactly is new in each new build. Thus, when you try it out you don't always see the difference because you don't know which area to look into. Is there any resource anywhere on this website or somewhere else (perhaps, on GitHub) informing us briefly on how each new build is different from its immediate predecessor?