Currently builds from the same commit can slightly differ.

A reproducible build scenario (documented) is needed and should be used by default (same source = same binary).

Some reading: https://reproducible-builds.org/_lfs/presentations/2015-08-13-CCCamp15.pdf

Most of the needed pieces of that are already there.