Hrmm, it makes performance claims with regard to Buck1 but not to Bazel, the obvious alternative. Hardly anyone uses Buck1 so you'd think it would be relevant.
The author of Bazel came over to FB and wrote Buck from memory. In Google it’s called Blaze. Buck2 is a rewrite in rust and gets rid of the JVM dependence, so it builds projects faster but it’s slow to build buck2 itself (Rust compilation)