Add a buildsystem

[alvarogalloc]

I Like to build my projects in ninja, and for that and other further persons who'd like others than make, vs or xcode

[paulocoutinhox]

Better is add support for CMake

[alvarogalloc]

That's what I meant, but i mean it in general, it could be anyone: Cmake, premake, meson, etc. But my fav is cmake