Recently an ex-team member of mine received negative feedback on an approach to consolidate on a single datastore. The intent was to focus all of their infrastructure knowledge on ONLY Postgres. This was for a fairly normal Ruby on Rails application that already liberally utilized a handful of innovation tokens.
The concept of these is actually quite old in 2024, so this post should help: Choose Boring Technology
This individual's idea would be to utilize Postgres for queuing, database interactions, and with Solid Cache; caching both GraphQL Response Fragments and Rails cache needs. The heresy though of removing complexity, especially at the infrastructure level. Becoming focused on a single piece of technology is still considered a step backwards or 'pedestrian'. Doubly so, when teams take such a libaral use of innovation tokens at the beginning of an application.
Relentless simplicity is a great marker of senior (even staff) engineers. A fairly smart human and someone quoted frequently on this blog has a good amount of thought on this topic: