As a SRE I was going to make a comment about missing basic metrics like RED or structured logging but at the end you mentioned you like ELK APM and used it so indeed it's very opinionated as ELK is not a ready-to-use cheap solution people would use as their first choice IMHO.
As a SRE I was going to make a comment about missing basic metrics like RED or structured logging but at the end you mentioned you like ELK APM and used it so indeed it's very opinionated as ELK is not a ready-to-use cheap solution people would use as their first choice IMHO.