Sentry.io is using ClickHouse for search, with an API they built on top of it to make it easier to transition if need be. They blogged about it at the time they adopted it:
I like sentry but it's the only app that I know uses 25 or so containers to stich itself together to get running which seemed insane, not to mention the usage of much ram.
https://blog.sentry.io/2019/05/16/introducing-snuba-sentrys-...