UBT is a blessing and a curse. I've spent a lot of time with it, and contributee to it. It's definitely not the fastest of build tools, the change detection takes a few seconds even on powerful hardware. The way it handles UHT (the codegen step of unreal) isn't great either.
It has a nasty habit of getting itself stuck, and it's got a horrific architectural decision of only allowing one instance of the process to run at a time (and see previous point, it gets stuck). Combine those two with modern IDEs that call the build tool in the background and you bet a messy situation.
But the adaptive unity build is probably one of the coolest features I've ever seen in a build system
It has a nasty habit of getting itself stuck, and it's got a horrific architectural decision of only allowing one instance of the process to run at a time (and see previous point, it gets stuck). Combine those two with modern IDEs that call the build tool in the background and you bet a messy situation.
But the adaptive unity build is probably one of the coolest features I've ever seen in a build system