Kyoto Tycoon vs Amazon QLDB: What are the differences?

Kyoto Tycoon: A handy cache/storage server. Kyoto Tycoon is a lightweight database server with auto expiration mechanism, which is useful to handle cache data and persistent data of various applications. Kyoto Tycoon is also a package of network interface to the DBM called Kyoto Cabinet; Amazon QLDB: A fully managed ledger database. It is a fully managed ledger database that provides a transparent, immutable, and cryptographically verifiable transaction log ‎owned by a central trusted authority. It can be used to track each and every application data change and maintains a complete and verifiable history of changes over time.

Kyoto Tycoon and Amazon QLDB can be categorized as "Databases" tools.