To be honest Postgres and DuckDB are on my lists to really get my hands dirty with.
One of the more interesting talks I read about was how someone used MySQL's bin log to mirror a lakehouse different versions of data and used DuckDB as the compute layer of a lakehouse. I think the talk was held in South America, so I didn't get to go.
Postgres is just useful for pretty much everything it seems like lol. Knowing they work together so well makes for a side project to learn both.