universal SAT seems to work (yet dominoes are broken: box is unstable)
tree5f2acf48baf3ffa0da97d2214b8f87b22eb18082
-rw-r--r-- 38575 b2dlite.d
-rw-r--r-- 11223 ncdmain.d
-rw-r--r-- 17616 xmain.d