http://i3xi5qxvbrngh3g6o7czwjfxwjzigook7zxzjmgwg5b7xnjcn5hzciad.onion/proposals/226-bridgedb-database-improvements.html
Other potential uses of the improved Bridge database system
Redis provides mechanisms for evaluations to be made on data by calling
the sha1 for a serverside Lua script. [15] While not required in the
slightest, it is a rather neat feature, as it would allow Tor's Metrics
infrastructure to offload some of the computational overhead of gathering
data on Bridge usage to BridgeDB (as well as diminish the security
implications of storing Bridge descriptors).