[whs]

It's documented here https://store.steampowered.com/oldnews/35534?l=

I don't think I ever found more documents on this feature. I assume it might need lots of users with matching result to ensure that bad actor can't upload malicious shader.

[voodooEntity]

Thank you for linking, and it makes sure to say you have to have a certain set of proofs to make sure no malicious code is injected as a precompiled shader sounds like a great place for exploitation.

Tho i would expect (naive me) that the shaders at least might be cached locally - which is not the case since as i mentioned in my comment have to recompile them for every game every time i start.