API Versioning Explained

Manage API evolution gracefully — maintaining multiple versions so clients can migrate at their own pace without breaking their integrations.

API Versioning

API versioning is the practice of managing changes to an API over time by maintaining multiple versions simultaneously, allowing clients to migrate at their own pace without breaking existing integrations.

Explanation

As APIs evolve, breaking changes (removed fields, renamed endpoints, changed response formats) can break client applications. API versioning lets you introduce breaking changes in a new version while maintaining the old version for existing clients. Common strategies include URL path versioning (/v1/users, /v2/users), header versioning (Accept: application/vnd.api+json;version=2), and query parameter versioning (?version=2). URL versioning is the most explicit and widely used. Semantic versioning (major.minor.patch) communicates the nature of changes. Deprecation policies give clients time to migrate before old versions are retired.

Bookuvai Implementation

Bookuvai uses URL path versioning as the default API versioning strategy. We maintain backward compatibility within major versions, document breaking changes in migration guides, and provide deprecation warnings with timelines. API clients receive notifications before version retirement.

Key Facts

  • Maintains multiple API versions for backward compatibility
  • Strategies: URL path, header, and query parameter versioning
  • URL path versioning (/v1/, /v2/) is the most common approach
  • Deprecation policies give clients migration timelines
  • Semantic versioning communicates the nature of changes

Related Terms

Frequently Asked Questions

Which API versioning strategy should I use?
URL path versioning (/v1/users) is recommended for most APIs because it is explicit, easy to understand, and simple to implement. Header versioning is cleaner but harder for clients to discover. Query parameters are easy but pollute the URL space.
Does GraphQL need versioning?
GraphQL typically avoids versioning by deprecating individual fields instead of creating new API versions. Clients request only the fields they need, so adding new fields is always backward compatible. Deprecated fields are marked and eventually removed.
How long should I support old API versions?
Industry standard is 12-24 months deprecation notice. Communicate timelines clearly, monitor usage of old versions, and provide migration guides. Some APIs support old versions indefinitely for enterprise clients under contract.