Pipeline DB would be a great fit, it seems, for 'Speed-layer' part of lambda architecture. While the postgresql underneath would work as a 'batch layer'.

A pair of both would only be missing an in-memory and on disk column-oriented 'analytics' tier (perhaps as separate instance that's being continuously fed from the first two?).

I think I had seen that PostgreSQL also has columnar store extension, wondering if that would work close the remaining gap for the analytics instance.