TanStack DB is a reactive client store built on differential dataflow that extends TanStack Query with collections, live queries, and optimistic mutations. It normalizes data into typed collections, enables sub-millisecond cross-collection queries, and provides instant optimistic updates with automatic rollback on failure.
When to use: Reactive UIs needing local-first data, cross-collection joins with live updates, optimistic mutations with automatic sync, real-time sync via ElectricSQL or other backends, apps that outgrow TanStack Query's per-query caching model.
When NOT to use: Simple fetch-and-display (TanStack Query alone suffices), server-components-only apps, purely synchronous local state (useState/Zustand), GraphQL with normalized caching (Apollo/urql).
Base de datos del lado del cliente reactiva TanStack DB con consultas en vivo y mutaciones optimistas. Úselo al crear interfaces de usuario reactivas con datos locales primero, motores de sincronización o actualizaciones optimistas. Úselo para tanstack-db, consultas en vivo, mutaciones optimistas, motor de sincronización, base de datos reactiva, local primero. Fuente: oakoss/agent-skills.