# Versioning (Must Read)
source: https://developer.mastercard.com/mastercard-processing-credit/documentation/api-basics-section/versioning/index.md

As per Mastercard standards, the Mastercard Processing APIs do not have any versioning in interfaces to ensure backward compatibility and avoid breaking changes.

Here is a list of what can be considered breaking and non-breaking changes.

|                   Backward-compatible (non-breaking) changes                   |                        Backward-incompatible (breaking) changes                         |
|--------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------|
| Adding an API interface to an API service                                      | Removing or renaming a service, interface, field, method, or enum value                 |
| Adding a method to an API interface                                            | Changing an HTTP binding                                                                |
| Adding an HTTP binding to a method                                             | Changing the data type of a field                                                       |
| Adding a field (optional field or contains default value) to a request message | Changing a resource name format                                                         |
| Adding a field to a response message                                           | Changing the visible behavior of existing requests                                      |
| Adding an output-only resource field                                           | Changing the URL format in the HTTP definition                                          |
| Adding a new optional query parameter with a default value (?parameter=value)  | Adding a read or write field to a resource message                                      |
| Adding an HTTP header field to a request/response message                      | Modifications (adding or modifying) a value to an enum in a response                    |
| Adding a new error code                                                        | Adding a new mandatory field to a request message without setting a field default value |

The listed items are not comprehensive. It only indicates what can be considered a breaking or non-breaking change.
Alert: You must adhere to these guidelines by writing an application in a way that backward-compatible changes (for example, adding a new field to a response) will not cause errors on your side. Mastercard Processing provides a minimum of 3 months' notice for changes to the APIs.