Does your engine build solution configuration match your games one? Fe. have you built the Engine in Debug - Win64 and Debug Editor - Win64 when you want to use your Game in Debug config? I think if they dont match it will recompile all. And take care what you click, “Rebuild” your game will lead to rebuild everything. Look at my answer here Problem: The engine compiles every time we do changes to our project - C++ Gameplay Programming - Unreal Engine Forums. Im sorry if you did all that and it does rebuild anyways, I wouldnt know how to help further. I hate that the engines build system wants to rebuild everything on all thinkable occasions too. Lost so many hours waiting…