See https://github.com/Netflix/dynomite/ .
This may work as a simpler (to compile/configure) alternative to mcrouter. I need to see what kind of multi-DC support it has. The support mcrouter has is just best-effort sync operations (logged on failure per host on a file nothing uses itself) for all operations of a certain type. That should not be hard to match. DC prefix (as long as is doesn't show up in keys) routing or similar features in other systems could be supported by WAN cache if needed without much effort.