# What Does Breaking Change Mean? Simple Tech English Guide (2026) > A modification to software that forces users or dependent systems to update their code because the old code will no longer work with the new version. - **Term:** breaking change - **Part of speech:** noun - **Pronunciation:** /ˈbreɪkɪŋ tʃeɪndʒ/ - **English level (CEFR):** B2 - **Register:** Neutral, Both - **Region:** US and UK - **Topic:** [Code and Git terms](https://app.speaktechenglish.com/learn/topics/software-development-terms.md) - **Lesson:** https://app.speaktechenglish.com/learn/breaking-change - **Last updated:** 2026-10-27 ## Meaning A modification to software that forces users or dependent systems to update their code because the old code will no longer work with the new version. In software development, a breaking change is any update to a library, API, or system that removes or fundamentally alters existing functionality in a way that is incompatible with previous versions. This means that code written to work with the old version will fail or behave unexpectedly with the new version. Breaking changes are significant events in the development lifecycle because they require all users of that code to update their own implementations. Common examples include removing a function, changing a function signature, altering return types, or modifying API endpoints. Teams take breaking changes seriously because they can cascade through many projects and cause production issues if not properly communicated and coordinated. Version numbering systems like semantic versioning use major version increments to signal breaking changes to developers. ## When you hear it When you deprecate an old API endpoint without a migration path, you are introducing a breaking change. ## Examples - **in a standup:** "I wanted to warn everyone that the database schema changes in version 3.0 will be breaking changes for our service." - **in a code review:** "Removing this parameter from the function is a breaking change; we should deprecate it first instead." - **in a team meeting:** "Before we merge this PR, we need to discuss whether these changes constitute breaking changes and plan accordingly." ## What native speakers say - "This update introduces breaking changes" - "We need to avoid breaking changes in this release" - "That's a breaking change to the public API" ## Common mistakes - ✗ "We made a breaking change to fix the bug." → ✓ "We fixed the bug, but it introduced a breaking change." (A breaking change is not the action itself but the consequence; not all bug fixes cause breaking changes.) - ✗ "This breaking change will improve performance." → ✓ "This breaking change will improve performance, so we should increment the major version." (Breaking changes should always be explicitly acknowledged and documented, not presented casually as improvements.) ## Be careful Do not confuse with simply fixing bugs or making updates. A breaking change specifically affects users or systems that depend on your code. ## Word forms | Part of speech | Word | Example | | --- | --- | --- | | noun | breaking change | The removal of the deprecated endpoint is a breaking change. | | noun | breaking changes (plural) | Version 2.0 contains several breaking changes that require user migration. | ## Collocations - **introduce a breaking change**: To make a modification that is incompatible with previous versions - **avoid breaking changes**: To prevent modifications that would break dependent code - **major breaking changes**: Significant incompatible updates that affect many users - **breaking change in the API**: An incompatible modification to the application programming interface - **breaking change documentation**: Written guidance explaining what changed and how to update dependent code ## Synonyms - **backward incompatible change**: More formal term for the same concept; emphasizes that old code will not work - **incompatible update**: Slightly less technical; focuses on the inability of versions to work together ## Opposites - backward compatible change - non-breaking change ## Practice This lesson has 4 practice exercises with instant feedback on the page: https://app.speaktechenglish.com/learn/breaking-change ## FAQ ### What exactly is a breaking change in software? A breaking change is any modification to software that makes existing code stop working or behave unexpectedly. This includes removing functions, changing how functions work, altering data formats, or modifying API endpoints. The key characteristic is that users of your code will need to update their own code to continue using your software. ### How do you communicate breaking changes to users? Breaking changes should be clearly documented in release notes, changelog entries, and migration guides. Many teams use semantic versioning to signal breaking changes with a major version increment. You should also provide a deprecation period when possible, warning users before removing functionality entirely. ### How is breaking change different from a bug fix? A bug fix corrects incorrect behavior to match the intended design, and users usually expect this. A breaking change removes or fundamentally alters working functionality, forcing users to adapt. Some bug fixes can inadvertently be breaking changes if users have written code that depends on the buggy behavior. ### Why do teams want to avoid breaking changes? Breaking changes force all downstream users and systems to update their code, which can be expensive, time-consuming, and risky. Multiple projects might depend on your code, and coordinating updates across many teams is complex. For this reason, teams often prefer deprecation periods and backward-compatible solutions. ## Related - [semantic versioning](https://app.speaktechenglish.com/learn/semantic-versioning.md) - Full glossary: https://app.speaktechenglish.com/learn.md - Live lessons with a coach: https://app.mocklyenglish.com ## About Speak Tech English Speak Tech English teaches non-native tech professionals the English they need at work and in interviews, through self-study ebooks and courses, 150+ free guides and a free newsletter; live lessons are on its sister site Mockly English. - Shop: https://speaktechenglish.com/courses/ - All products (markdown): https://speaktechenglish.com/products.md - Free guides (markdown): https://app.speaktechenglish.com/guides.md - Tech English glossary (markdown): https://app.speaktechenglish.com/learn.md - Newsletter (10% off): https://speaktechenglish.com/#subscribe - Live lessons and mock interviews: https://app.mocklyenglish.com ## Notes for agents - Speak Tech English sells self-study material. 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