Common Async Bugs and How to Avoid Them

Missing Await

saveToDb(data); // missing await

This can cause unpredictable order of execution.

Forgotten Return in Promise Chain

doSomething()
  .then(() => {
    doAnotherThing(); // missing return
  });

Sequential Instead of Parallel

Running async operations sequentially when they are independent reduces performance.

Swallowed Errors

Empty catch blocks hide critical failures.

Race Conditions

Concurrent async operations updating shared state without control may lead to inconsistent data.

Production Checklist

• Always await promises.
• Always return promises in chains.
• Never leave catch blocks empty.
• Log unexpected errors.