[DuckConference]

Their performance claims are quite a bit ahead of the distributed android build systems that I've used, I'm curious what the secret sauce is.

[cogman10]

Is it going to be anything more than just a fancier ccache?

[vlovich123]

It’s definitely not ccache as they cover that under compiler wrapper. This works for Android because a good chunk of the tree is probably dead code for a single build (device drivers and whatnot). It’s unclear how they benchmark - they probably include checkout time of the codebase which artificially inflates the cost of the build (you only checkout once). It’s a virtual filesystem like what Facebook has open sourced although they claim to also do build caching without needing a dedicated build system that is aware of this and that part feels very novel