What mechanism ensures that clients can migrate to newer APIs without breaking?

What mechanism ensures that clients can migrate to newer APIs without breaking?

• A. Never deprecate any API to avoid breaks.
• B. Perform clandestine migrations with no notices.
• C. Apply semantic versioning, with deprecation timelines and migration guides.
• D. Only update clients, not servers.

Answer: (C)

Structured, predictable API evolution relies on communicating changes clearly and providing a defined upgrade path. Semantic versioning signals compatibility at a glance: major versions indicate breaking changes, while minor and patch releases stay backward compatible, so clients can plan upgrades without surprises. Deprecation timelines give advance notice of features slated for removal, preventing sudden breaks. Migration guides accompany releases to show exact code and configuration changes needed. Together, these practices create a stable, maintainable path for clients to migrate to newer APIs. The other approaches fall short because they hide changes, enforce updates without warning, or ignore server-side changes that clients rely on.