SlateDB
A cloud native embedded storage engine built on object storage
...The trade-off is that object storage has a higher latency and higher API cost than local disk. To mitigate high write API costs (PUTs), SlateDB batches writes. Rather than writing every put() call to object storage, MemTables are flushed periodically to object storage as a string-sorted table (SST). The flush interval is configurable. To mitigate write latency, SlateDB provides an async put method.