Hi Jonathan

Good overview, looks cool and modern. I have a few quick questions.

Inter-DC replication was covered, how do you handle replication between DC-s, do you rely on the storage services like Cassanda replication implementation for Cassandra, Riak for Riak etc ?

Do you do any Chaos Monkey like tests and how quickly monitoring picks up any issues with the services ? What do you use for alerting about issues, is it part of monitoring or a separate sub-system ?

How do you do authentication between the micro-services, is it cert based ?

Depends on your DC setup, but how do you choose the media services for real-time processing in geographically sparse participants ?

Anyway, I have more questions, but looking forward to more deep dives!