I built a similar pipeline using Kafka and ClickHouse - it's amazing how easy it is nowadays to ingest and analyze billions of events a day using standard tools.
ClickHouse can even ingest directly from Kafka (courtesy of Cloudflare - http://github.com/vavrusa contributed it).
ClickHouse can even ingest directly from Kafka (courtesy of Cloudflare - http://github.com/vavrusa contributed it).