SyncPromise is a tiny (< 1 KB) promise library that resolves and rejects **synchronously** instead of following the Promises/A+ async requirement. It is designed for developers working with IndexedDB transactions—where native promises can prematurely close a transaction—by providing a safe, familiar‑looking API that guarantees no mixed synchronous/asynchronous resolution and forces rejection handling. Suitable for web apps or libraries that need deterministic, in‑transaction promise chaining.