Every platform api has a ceiling, and every naive integration hits it on the worst possible day. The fix is to design for the limit from the first line, not to discover it in production.

Start by batching. One call that fetches a hundred orders beats a hundred calls that fetch one, and most apis reward you for asking that way. Then queue. When you must make many calls, spread them behind a rate-aware worker instead of firing them all at checkout.

The last piece is backoff. When the api says slow down, slow down, and retry with widening gaps rather than hammering until you are banned.

A sync that respects the ceiling is boring on a normal day and heroic on a busy one. Boring is the goal.