FrontendHaltNetworking·Intermediate·Conceptual·1 min read
What does stale-while-revalidate mean at the application data layer?
Short interview answer
On access, the client immediately returns the cached value if present, then fetches fresh data in the background and updates the cache and UI when it arrives. The user sees something instantly and it becomes correct shortly after, instead of waiting on every navigation.
Key takeaway
Explain the underlying mental model clearly, then support it with a concrete example and its trade-offs.