#22 Nine Layers of Sky by Liz Williams

This blends Russian folklore with the fallout of Communist Russia.  There is an alternate universe that communism is still going great guns  and it intersecting with our universe as they try to close the gate to stop their communism from going away. The heroine here is a former scientist that has lost her job at Star City and by chance comes across one of the keys to the gate to the other world. It was a bit different and I really liked, just like I have liked everything she has written.