Sorry but spotify's infrastructure is not a shiny beacon of correctness.

They've compounded mistake upon "Oooshiny lets use that"

here is a post where someone dissects spotify's infrastructure bit by bit: http://www.secretbatcave.co.uk/software/docker-and-you/

This isn't an anti google compute, its got some really great features. But, spotify's backend infrastructure ain't one

Yes, I appreciate that that post is from a while ago, and they might have completely paid back that massive technical debt/innovation token debt.