Breaking API changes without versioning
A "breaking change" is any change that causes previously working clients to fail. When these changes happen without a version bump or clear communication, they are effectively silent contract breaks.
Examples of unversioned breaking changes
- Removing fields that clients still treat as required.
- Changing field types (number to string, object to array, etc.).
- Adding new enum values that older clients do not recognise.
How to detect them quickly
Use the HTTP Contract Drift Inspector to compare known-good payloads with what your API returns today. It flags missing fields, type mismatches, structural changes, and enum-like drift.
Combine this with the OpenAPI Silent Failure Validator to see where your documented contract no longer reflects reality.