FrontendHaltTesting·Intermediate·Conceptual·1 min read
How do unit, integration, and end-to-end tests differ?
Short interview answer
Unit tests isolate small logic, integration tests verify collaborating modules or rendered features, and end-to-end tests exercise deployed user journeys through real boundaries. Use the cheapest level that gives confidence in the risk, not a fixed percentage pyramid.
Key takeaway
Explain the underlying mental model clearly, then support it with a concrete example and its trade-offs.