Glossary term
What is HMAC (Hash-based Message Authentication Code)?
HMAC stands for Hash-based Message Authentication Code.
In System Design
Proves a message wasn't changed and came from a key holder. Example: Signing webhooks.
Learn it properly · System DesignLesson 34: Idempotency, Pagination & API VersioningA retried payment that charges twice, a list endpoint that loads three million rows, a renamed field that crashes every old app. Idempotency keys, cursor pagination and careful versioning — the unglamorous details that separate a demo API from a production one.In API Design
A way to sign a message with a shared secret so the receiver can check it was not changed and came from the sender.
Learn it properly · API DesignLesson 5: Idempotency Keys, Retries, Webhooks and Rate LimitsSafe retries with idempotency keys, webhooks with signatures and retries, rate limit headers, and long-running jobs.