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APIs
HTTP, REST, auth, pagination — the interfaces between services.
- •150 XPHTTP Methods Deep DiveSafety, idempotency, and when to use PATCH vs PUT.
- •150 XPStatus CodesThe full taxonomy and when to pick each code.
- •200 XPAPI Auth PatternsAPI keys, bearer tokens, OAuth 2 PKCE, and JWT anatomy.
- •175 XPPagination and VersioningCursor vs offset, bulk endpoints, and breaking-change policy.
- •175 XPIdempotency KeysHow payment APIs survive retries.
- •175 XPError ShapesProblem+JSON, validation envelopes, and retryable errors.
- •200 XPWebhooksOutbound HTTP, signing, retries, and dead-letter handling.
- •200 XPgRPC vs RESTSchema-first, streaming, and when each fits.
- •200 XPAPI Design ReviewWhat to actually look for in an API PR.