As a C++ developer (admittedly Linux-oriented) looking at TDM as a potential project, I'll say that scons is a red flag that the compilation process is not going to be friendly (and it's not -- I can't even get past the pch). I'd argue cmake is not only more familiar (to modern Unixy people), but also more ubiquitous (on Unix-based machines). If most of the devs on TDM are Windows users, the underlying build system should matter very little to them, since they're just using MSVC, etc. Who it really matters to are the people that don't have that luxury, or choose to do things differently (i.e. users at a shell). In which case, familiarity is the luxury. A counter argument would be that the existing devs are more familiar with scons and therefore scons should remain. That would be a valid argument, assuming said devs are not looking to open TDM to a broader variety of developers (but I believe they are -- or at least should be).