The missing await bug in JavaScript async functions

The quick answer

Add await before the call that returns a Promise. Without it, the returned value is a Promise object, so reading a property or calling a method on the expected data does not behave as you intend.

A minimal example

async function showUser() {
  const user = getUser();
  console.log(user.name);
}

async function showUser() {
  const user = await getUser();
  console.log(user.name);
}

How to debug it

1. Find every call that returns a Promise: fetch, database drivers, and most I/O.
2. Check whether the returned value is used directly on the next line.
3. Follow the value: if a Promise is treated like plain data, an await is missing.
4. Add await, or return the Promise so the caller can await it.

Common wrong fixes

• Wrapping the call in another Promise instead of awaiting the one you already have.
• Adding .then in one place but leaving the value used synchronously right after.
• Marking the function async without ever awaiting the Promise inside it.

Limits of this guide

This covers the single-missing-await case. Real async bugs also include unhandled rejections, races between concurrent awaits, and ordering across event loops. The challenge focuses on the ordering mistake shown here.

Authoritative references

1. ECMAScript language specification — Await
2. MDN — async function
3. MDN — await operator

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