[gkaemmer]

Our data is primarily stored in postgres. We've looked into using Mongo to store FHIR-compliant documents, which is the newest standard (and best standard, IMO) proposed by HL7.

Haven't looked at that many immutable databases, but they seem interesting. Most of the time medical data does not require many writes (rarely are two doctors editing your record simultaneously), but the audit trail that datomic provides could be very useful as a built-in feature.