obigstore is an open-source database that exposes a multidimensional BigTable-like data model. It inherits Google LevelDB's fundamental strengths, such as fast random writes or control over the physical data layout. It can be used in a client/server setting or as an embedded database.

strong data durability guarantees

fully fsync'ed writes with group commit
data integrity ensured with CRCs at the protocol level
synchronous and asynchronous replication
online backup

rich semi-structured data model

atomic transactions (both read-committed and repeatable-read isolation levels)
optimistic and pessimistic concurrency control
asynchronous notifications
limited support for complex documents (BSON serialized)
support for composite keys (REPL and client lib)

performance

fast random writes
efficient range queries thanks to spatial locality
cross-record redundancy reduction at the page level (snappy compression)
fast recovery (independent of dataset size)

1 billion writes on 1 EC2 node, sequential
no fsync

1 billion writes on 1 EC2 node, random hotspot, fsync()ed