The ignore_dirs configuration option has no effect at all.
While the .temp directory, that the SDK writes to, is hardcoded and ignored, other directories like .git are watched and therefore most git operations trigger one or multiple rebuilds while vmb watch is active.
Sometimes modders have to switch between VT1 and VT2 when compiling mods, and it's very frustrating to recompile everything every time. The compilation time can reach up to 5 mins for the mods working with shaders. Dividing precompiled files would be a good idea.