developer experience

Rate limits protect capacity and fairness, and they shape the developer experience as much as any feature on the API. The interviewer wants limits by dimension, tiers that grow with trust, and clear behaviour when limits hit.

Activation is the developer platform's equivalent of a product's first-run experience. The interviewer wants a diagnosis from real sessions and a set of fixes that remove each step of friction.

Leaked keys are common and costly. Refund once with conditions, then change the defaults: scanning and automatic revocation, narrow key scopes, spending limits for new accounts and prepaid options.

Server-side state simplifies integration and can improve caching, but it means storing data and it does not make old tokens free. Offer it as an option with short retention and give zero-retention customers an equal stateless path.