Before the latest optimization, and only using 1 core, vs. SQLite we were seeing 133x performance on a basic group by or join, and about 4x for a pretty complex query. It was roughly even to Pandas in performance, but it can scale to larger than memory data and now it can use multiple cores! As an example, I could build views from 2 Pandas DataFrames with 2 columns and 1 million rows each, join them, and return the 1 million row dataset back to Pandas in 2 seconds vs. 40 seconds with SQLite/SQLAlchemy... Pretty sweet. DuckDB is going to be even faster now I bet!