I'll write down the options and you can tell me which one works or not works for you - access lakefs using

s3://

. When you run duckdb cli from the command line not inside the docker image or docker compose you will need to access lakefs though the external host/port - localhost:8500 (and probably install and load httpfs). When you run duckdb cli from inside the container using exec - in your case

docker compose exec -it lakefs duckdb

lakefs will be resolved using localhost:8000. So having the

SET s3_endpoint='localhost:8000';

should work for you. If you are running the duckdb cli inside the docker-compose but not from the lakefs itself - use lakefs:8000.