# Ascending compatibility in Ansible

**URL:** <https://forum.ansible.com/t/ascending-compatibility-in-ansible/12146>\
**Category:** Ansible Project\
**Created:** [December 18, 2012, 9:59am UTC](https://forum.ansible.com/t/ascending-compatibility-in-ansible/12146 "2012-12-18T09:59:17Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Acyl](https://avatars.discourse-cdn.com/v4/letter/a/bc79bd/32.png) [@Acyl](https://forum.ansible.com/u/Acyl)\
**Post date:** [December 18, 2012, 9:59am UTC](https://forum.ansible.com/t/ascending-compatibility-in-ansible/12146/1 "2012-12-18T09:59:17Z")

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Hello,

Within the framework of testing Ansible in a large-scaled use, I am asking today a question to myself that the documentation doesn’t seem to answer.

Does the Ansible project guarantee an ascending compatibility of Playbooks, modules and callbacks?

Please excuse my English which I think is not perfect, I’m French.

Best regards  
Acyl

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**Author:** ![Michael\_DeHaan](https://avatars.discourse-cdn.com/v4/letter/m/c4cdca/32.png) [@Michael\_DeHaan](https://forum.ansible.com/u/Michael_DeHaan)\
**Post date:** [December 19, 2012, 1:50am UTC](https://forum.ansible.com/t/ascending-compatibility-in-ansible/12146/2 "2012-12-19T01:50:55Z")

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The short answer is "yes". The long answer is "yes, but we might not  
be 100% perfect". We fight really hard to make sure things remain  
compatible and we don't remove anything.

There are occasionally small differences in undocumented behaviors --  
but we try to minimize those as well. Nothing has really gone away  
in the last several releases and moving forward I want this to be even  
more locked down.

Callbacks should be added over time, but not removed, and they are  
already written in such a way that if you don't have a particular  
callback it won't crash on you for not having a hook for it.

API compatibility for scripts is also important -- and as things are  
changing structurally less and less, I am more confident to say  
compatibility is going to be even more the case than now.

I think most people here would agree with that, save for, like I said,  
undocumented behaviors changing around occasionally.

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**Author:** ![Acyl](https://avatars.discourse-cdn.com/v4/letter/a/bc79bd/32.png) [@Acyl](https://forum.ansible.com/u/Acyl)\
**Post date:** [December 19, 2012, 9:37am UTC](https://forum.ansible.com/t/ascending-compatibility-in-ansible/12146/3 "2012-12-19T09:37:43Z")

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> Thank you very much for this complete answer.

Best regards.