Implement consistent hashing, and explain where it matters for sharding embeddings or routing requests.
When you shard a vector index or route requests across model replicas, naive 'hash mod N' reshuffles everything the moment N changes. Consistent hashing moves only a small fraction. Here is the implementation.
Updated Sep 2026 · Grounded in real GenAI, LLM, and AI/ML engineering interview loops and written to a senior-engineer editorial bar.
When you shard a vector index or route requests across model replicas, naive 'hash mod N' reshuffles everything the moment N changes. Consistent hashing moves only a small fraction. Here is the implementation.
Lead with where the obvious approach breaks, because that is the judgment they are screening for — most candidates jump straight to the happy path and lose the room.
Then walk the failure back through the pipeline in order, naming the one metric the customer's exec sponsor actually cares about before you propose the fix.
