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FE System DesignAdvanced50 minutes

Offline-First PWA

Design an offline-first progressive web app with service workers, sync, caching, and conflict resolution.

LLM-friendly summary

An advanced frontend architecture problem about offline-first PWAs, syncing local state, and handling conflicts safely.

Scenario

Field teams work with unreliable connectivity and need the app to stay useful offline, then reconcile cleanly when back online.

What you need to design

  1. 1Define cache and sync behavior.
  2. 2Handle writes and conflict resolution.
  3. 3Explain service worker responsibilities.
  4. 4Support partial availability and degraded UX.
  5. 5Plan instrumentation for failure recovery.

Concepts

Service WorkersIndexedDBSyncConflict Resolution

Skills

Offline ArchitectureData ConsistencyProgressive Enhancement

What good solutions are evaluated on

  • - Offline data model and sync flow
  • - Cache boundaries and invalidation
  • - Conflict resolution quality
  • - Recovery and observability

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Open the interactive AlgoReason workspace to sketch the architecture, write notes, and submit for AI evaluation.

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