I was trying to buy (for Museum variety) a Ruins—specifically a Survivors—in my last game; every time I did, the game would soft-lock and my turn would not progress. I would have to undo and do something else to finish my turn. The pile had a Tax of 1 Debt on it, but would freeze regardless of how many coins I had left when I bought it.
Game #1717660
will be fixed in the next release...
There was a problem in setup order here, with the interaction of Embargo (piles can have embargo tokens) and Cultist (add the ruins pile).