> Interesting. Could you elaborate on the benefit of this?

I don't know on what I can elaborate.

Storing integers that are near each other is much more optimal in a RoaringBitmap than in a flat array. The reason is that it will only store the integers by storing the high part once and the low part in an array or bitmap efficiently.

Also we already use RoaringBitmaps on the other end of Meilisearch and converting that to another data structure could take a lot of times.