Browser Storage

Outcome: Design or review Browser Storage for this system while keeping data correct, secure, and easy to operate. User context: An offline app keeps drafts in IndexedDB and a display choice in localStorage. It syncs after reconnecting. Technical concept or control: Browser Storage. Why it fits: Use it for recoverable drafts, offline data, caches, or local choices. Match the API to the data. Do not use it when: Do not keep secrets or sole business records in script-readable storage. Plan for eviction and shared devices. Engineering requirements: Define inputs, outputs, contracts, and rules that must always hold. Set authorization and input checks. Define failures, timeouts, retries, one-time effects, data moves, and compatibility limits. Operations: Add useful signals and logs that hide sensitive data. Set capacity limits and write an operator guide. Test recovery and rollback. Acceptance criteria: Contract and failure-path tests pass. Data and authorization rules still hold during retries and partial failures. Check performance limits, monitoring, recovery, and rollback. Evidence and limits (evidence boundary): No single official standard controls the whole term. Its meaning may change across teams, platforms, or frameworks. Unknowns to confirm: Where the code runs, data stores, traffic shape, consistency needs, and the security boundary. Also confirm the compatibility period, service goals, and rollback limits.