Kuzu is alive and well. The new name is LadybugDB. I’m the maintainer. Happy to answer any questions.
Kuzu was VC backed, but YC was not one of them. They were acquired by Apple.
LadybugDB (like the code base that was formerly called Kuzu) is an embedded columnar database that supports ACID properties and serializable transactions.
What does KuzuDB give you over e.g. Neo4j
No server to setup. Columnar is faster for analytical queries. Uses Apache Arrow based memory for internals. Also supports the Bolt protocol via a rust wrapper. Details on the LadybugDB blog.
Also see the companion project Icebug, which adds many graph data science (GDS) algorithms with the same columnar efficiency. Uses Apache Arrow instead of C++ std::vector to hold the graph. Page rank was measured to be 8x faster.