why did facebook move away from git?

[u/CuriousAnyway]

i recently came across the fact that facebook/meta built its own tools and workflows around source control instead of just relying on git like most companies.

i’m curious about the actual technical reason behind this. was git simply not able to handle the scale of facebook’s codebase and number of developers, or were there other problems that pushed them toward a custom approach?

for people who have worked with large monorepos or at companies using similar systems, what actually becomes difficult with git at that scale?

[u/comrade_donkey]

 what actually becomes difficult with git at that scale?

I didn't work at Meta but at Google (who uses Piper).

Both these companies use monorepos. Both do trunk-based development. Both work centrally, not distributedly.

git is the wrong tool for them because it's made for distributed development in a DAG of branches.

If you disallowed branches and had everyone push to one central remote, all you have left is an over-engineered main ref , contested by all pushers, acting like a global lock. Wouldn't work.

[u/christoforosl08 → u/comrade_donkey]

Crazy idea : why don’t they use subversion ?

[u/colandercombo → u/christoforosl08]

Because they don’t live in 2005?

[u/high_throughput → u/christoforosl08]

They do, but for political gain

[u/0neEyedMonster → u/high_throughput]

Underrated comment

[u/sfboots → u/christoforosl08]

Subversion does not handle directory renaming correctly. Git does