Design an artifact store on Kubernetes and Cassandra

A Java web API runs in Kubernetes on top of a Cassandra cluster and stores artifacts, each identified by a user-given name. An artifact must be created only once, even when several requests to create the same name arrive at the same time on different pods. Design how creation stays unique (lightweight transactions, conditional writes), how artifact bytes and metadata are stored, and how the service behaves under node failures and retries.