Hi, I'm working on using FB for UE4 in free time, but it seems the original release of FBv1.07 makes build time 3 times slower than UBT's default Parallel Executor, and it consumes a hell lot more memories. I speculate that FB fails to understand Unreal's PCH correctly: fastbuild#823.
If I understand your commits correctly, you have integrated the UnrealEngine\Engine\Extras\ThirdPartyNotUE\FASTBuild\fbuild_0.99.diff into FB v1.07?