https://nalar.dev/tags/api/ Recent content in API on Nalar Hugo en-us Tue, 01 Sep 2026 00:00:00 +0700 https://nalar.dev/backend/idempotency-keys-safe-api-retries/ Tue, 01 Sep 2026 00:00:00 +0700 https://nalar.dev/backend/idempotency-keys-safe-api-retries/ <p>Retries are essential in distributed systems. Networks fail, clients time out, load balancers reset connections, and responses sometimes disappear after a server has already committed a write.</p> <p>The dangerous case is a retry of a non-idempotent operation. If a client sends <code>POST /orders</code>, times out, and sends the same request again, the server may create two orders even though the user intended one.</p> <p>An idempotency key gives the client a stable identifier for one logical operation. The server remembers the result associated with that key and can return the same result when the request is retried.</p>