This lesson will rely on the built-in support for async functions found in Express 5 to demonstrate how an API can easily work with data asynchronously. By the end of the lesson our API will have the ability to save its notes to disk as they're added and read them when the server starts up again. First we'll update our Note model to persist data to the filesystem using the `MapStore` class created in a previous lesson. Then we'll access those updated methods on the Note model using the `await` keyword in our routes. We'll also briefly discuss the importance of catching errors that come from promises and async functions. **Resources** - To learn more about `async/await` read [Getting started with async/await](https://www.freecodecamp.org/news/getting-started-with-async-await-b66385983875/). - You can learn a great deal more about error handling in express in their guide to [error handling in express](http://expressjs.com/en/guide/error-handling.html).