# Backward-incompatible change

> A change that requires users or developers to change something on their side, like their configuration or their custom integration.

Source: https://contributors.home-assistant.io/glossary/backward-incompatible-change/

- In code: `breaking-change (label)`
- Also: backward-incompatible changes
- Formerly: breaking change (old name: don't use it in new text)

Pull requests with a backward-incompatible change get the `breaking-change` label, and explain in their description what changes and what to do about it. That text ends up in the **Backward-incompatible changes** section of the release notes.

The pull request template of Home Assistant Core and the label call it a "breaking change". Both mean the same thing. The release notes call it a backward-incompatible change, and so should everything you write.

When possible, a change is not backward-incompatible yet: it starts with a [deprecation](https://contributors.home-assistant.io/glossary/deprecation/) first.

## Related terms

- [Deprecation](https://contributors.home-assistant.io/glossary/deprecation/): Announcing that something will be removed in a later release, while it keeps working until then, so people can move on.
- [Release](https://contributors.home-assistant.io/glossary/release/): A new version of Home Assistant. One comes out on the first Wednesday of every month, with patch releases in between.
- [Pull request](https://contributors.home-assistant.io/glossary/pull-request/): A request on GitHub to merge a change into a repository, where it is reviewed before it goes in.