I can't see it being easy to take a 20 year massive code base and split it up into components that are so isolated enough they can live in different repositorie

I can't see it being easy to take a 20 year massive code base and split it up into components that are so isolated enough they can live in different repositories smoothly. As they say in: https://blogs.msdn.microsoft.com/bharry/2017/02/03/scaling-git-and-some-back-story/ https://blogs.msdn.microsoft.com/bharry/2017/02/03/scaling-g... The first big debate was – how many repos do you have – one for the whole company at one extreme or one for each small component? A big spectrum. Git is proven to work extremely well for a very large number of modest repos so we spent a bunch of time exploring what it would take to factor our large codebases into lots of tenable repos. Hmm. Ever worked in a huge code base for 20 years? Ever tried to go back afterwards and decompose it into small repos? You can guess what we discovered. The code is very hard to decompose. The cost would be very high. The risk from that level of churn would be enormous. And, we really do have scenarios where a single engineer needs to make sweeping changes across a very large swath of code. Trying to coordinate that across hundreds of repos would be very problematic.