Are Ubuntu builds deterministic? I assumed they are, that is, if I recreate the process of building Ubuntu installation media, I will get the same image, (bit-for-bit, with the same checksums) as the one on the Ubuntu mirrors.
Recent post by Joanna Rutkowska (lead developer of Qubes OS distro) suggests that it isn't so:
currently most projects, including all Linux distributions, do not build deterministically
Why not?