Alec Watts focused on backend stability in the TanStack/db repository, addressing a complex bug affecting live query reliability during garbage collection cycles. He resolved errors caused by finalized graphs being reused after collection garbage collection by implementing explicit cache resets for graph, inputs, pipeline, and collectionWhereClauses when subscriptions are unsubscribed and collections are collected. This approach ensured that each new live query execution compiles a fresh D2 graph, preventing runtime failures and improving cache lifecycle management. Working primarily with TypeScript and leveraging his skills in backend development and database management, Alec delivered a robust solution that enhanced real-time data consistency.