In memory partitions, yeah?
It's persisted to S3 storage, but SlateDB feels like it might sort of have some fit, maybe, as a scale-out distributed LSM-tree. https://slatedb.io https://news.ycombinator.com/item?id=41714858
There's an old 404 post too that looks like a reasonably on target introduction: Why SlateDB is the right choice for Stream Processing. https://web.archive.org/web/20241102212325/https://www.respo...