# save(completion:) Saves any changes you’ve made in the data store. ``` func save(completion: (@Sendable ((any Error)?) -> Void)? = nil) ``` ## Parameters `completion` A closure the method calls on completion of the save operation with an optional error value that indicates the reason for failure, if any. ## Discussion > Important: > You can call this method from synchronous code using a completion handler, as shown on this page, or you can call it as an asynchronous method that has the following declaration: > > ```swift > func save() async throws > ``` > > For information about concurrency and asynchronous code in Swift, see . > Important: > ClassKit calls your completion handler on an arbitrary thread. If you need to do work on a particular thread from inside the handler, dispatch that work to the appropriate queue. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)