You might want to look at:

• kissat/CONTRIBUTING

  Lines 1 to 3 in abfa45f

  	At this point we want to keep complete ownership in one hand
  	to particularly avoid any additional co-authorship claims.
  	Thus please refrain from generating pull requests. Use the issue

Sorry, I do not want to start a flame war here, but as I wrote somewhere else (probably for CaDiCaL), I will continue to keep the build process (and testing it) as simple as possible (and maintain) and thus will not support CMake directly. If you want (or need) CMake suport in your project you have to add it on your side (as others like 'Boolector' and 'CVC' are doing).