# Versions, deprecation and withdrawal

> How to know an operation is going away. Product side: API gateway; operations side: Serving your first API.

Guide - Since version 1.2.0 - Flexway v1.6.3 - https://flexway.io/en/docs/developer-versioning/

> How to know an operation is going away.
>
> Product side: [API gateway](https://flexway.io/en/docs/product-api-gateway/); operations side: [Serving your first API](https://flexway.io/en/docs/operations-first-api/).

| Source | What it says |
| --- | --- |
| The API's contract | `deprecated: true` on an operation, and its withdrawal date (`x-flexway-sunset`) |
| The console's catalogue | Each operation's owner, deprecation and withdrawal date |
| A2A | The request's `A2A-Version` header |

The `Sunset` and `Deprecation` headers toward callers are **not emitted yet**: read the contract or ask
the operator for the catalogue. The developer portal (catalogue, try-out, self-service keys) is planned
for `1.11.0`.

A `1.x` gateway keeps its error codes, headers and formats: a client written for `1.0.0` works on every
`1.x`.