I don't know the algorithm well enough to say for certain. but I get the impression it involves a clever work around to the interdependencies. it converts equalities and inequalities into a system of linear equations. It then converts this system into a matrix form it calls a "tableau". The solver appears to work by repeated applications of matrix operations which may be paralelizable. but I'm not sure. This is different from how physics engines resolve constraints, one after another. In a matrix form they just kind of all get optimised "at once"
