We use DuckDB to process analytics and feeds for Bluesky (https://bluefacts.app)

To get fast access to the query results we use the Apache Arrow interface and generate the code directly from DuckDB SQL queries using the SQG tool ( https://sqg.dev/generators/java-duckdb-arrow/)

I'm very interested to see a behind the scenes of your tech - do you guys have a writeup somewhere? You HN tool is also promising!