# Versioning

The Auvo API uses **URL versioning**: v2 lives under `/v2`. Compatible changes
(new optional fields, new endpoints) ship in v2; incompatible changes move to
the next major version.

## Deprecation policy

- A deprecated endpoint or field stays available for **at least 90 days**.
- Deprecations are announced via:
  - `x-deprecation-date` in the spec.
  - Response header `Deprecation: @timestamp`.
  - Weekly [changelog](/changelog).
  - Email to account admins that used the endpoint in the last 30 days.


## NOT breaking changes

- New optional fields in requests.
- New fields in responses.
- New endpoints / new verbs.
- New 2xx and 4xx codes with additional meaning.


## Breaking changes

- Removing/renaming fields or endpoints.
- Changing existing types/enums.
- Adding **required** request fields.
- Changing HTTP codes on existing operations.


## Communication channel

Subscribe to `changelog.rss` or follow our RSS/Atom feed. Webhook subscribers
receiving the `api.deprecated` event are notified too.