Status: IN
The consistent hash ring is a pure topology abstraction with no data-plane state: node operations are idempotent (add/remove on existing/missing nodes are no-ops), migration tracking is optional (callers pass keys in, the ring reports movements), and preference list construction automatically deduplicates physical nodes — making the ring a stateless function from key to node list that is safe to use concurrently and compose freely.
Idempotent ops + optional key tracking + auto-dedup = pure stateless routing function
Depends on (SL): ch-add-remove-idempotent, ch-migration-tracking-optional, ch-get-nodes-deduplicates-physical