Take the community feedback survey now.

Kevin Shea
Aug 5, 2022
  7892
(4 votes)

The A/B testing addon for Optimizely CMS is now open-source

Today we are announcing that we have open-sourced the A/B testing addon for Optimizely CMS 11 and Optimizely CMS 12. 

For several years, this tool has served as a springboard to the world of experimentation for CMS users and developers. That thrills us. Experimentation is a foundational pillar of Optimizely’s ethos and, in that spirit, we feel it’s important to maximize our focus on innovating in the areas that present the most effective results for our customers.  

Optimizely’s Web and Full Stack experimentation platforms provide the most advanced and robust experimentation capabilities on the market. It enables users with an immensely powerful set of tools for managing modern, dynamic, application experiences. It is also the platform upon which Optimizely will pursue its future innovation in the space. 

As we wind down our efforts on the addon, two factors standout: 

  • There are users that rely on the capabilities of the tool today.
  • The developer community has historically expressed interest in extending, modifying, or replacing capabilities within the tool. 

This makes the addon an ideal candidate to open to continue life as a community supported project. 

What happens next?

  • The source for the addon is now open and available at episerver/ab-testing (github.com). Fork the repository to add, update, or replace capabilities as it’s relevant to your projects.
  • Optimizely will continue to actively maintain support for the addon for 3 months, ending on November 15, 2022.
  • After November 15, 2022, Optimizely’s official contributions to the project will come to an end. The source for the addon will remain available to the community and free to use or modify as you see fit.

Happy experimenting!

EDIT: This article was updated to include a link to repository for the CMS 12 version of the add-on, in addition to the CMS 11 version.

Aug 05, 2022

Comments

Scott Reed
Scott Reed Aug 5, 2022 09:20 PM

Cool but to me it seems dissapointing this hasn't first been upgrade to support .NET 5/6 before being open sourced at this point in all honesty. 

This was one of the packages a client of our uses which we're about to do a platform upgrade and I was under the impression it was being upgraded and open sourced. Kinda dissapointing it's not been and I assume if you're only supporting for 3 months it won't be.

Kevin Shea
Kevin Shea Aug 8, 2022 02:35 PM

Hi Scott,

A great question. And you're correct, there is a .NET 6 version of the add-on currently available and still supported to ensure stability. This announcement is really centered around the add-on for CMS 11 and does not pertain to the CMS 12 version of the package. 

Mark Hall
Mark Hall Aug 8, 2022 02:48 PM

We have a seperate repo for CMS 12 which we will open source as well.  The decesion was to have seperate repos instead of one because of th amount of changes between netframework and net 5/6

Stefan Holm Olsen
Stefan Holm Olsen Aug 11, 2022 08:41 AM

Will community contributions be welcome in that repository (like in the Episerver.DeveloperTools repository)? Or will everybody have to fork it and make their own changes?

As I remember, this library needed some clean-up. Especially concerning anti-patterns.

Chris Banner
Chris Banner Aug 11, 2022 12:26 PM

Scott:
We've updated the article above to reference the repo for the CMS 12 version of the add-on, which is now also available.

Stefan:
Great question. Yes, we'll consider community contributions through November 15, 2022. If you prefer to fork it for better flexibility and control, you're welcome to do that also.

The add-on is certainly a product of a time when there were far fewer hooks and integration points in the CMS than there are today. It would benefit from update. Beyond it's implementation specifically though, we don't believe that a pipeline embedded A/B solution is ideal for the scale and distributed nature of today's applications. The add-on demonstrates the concepts of A/B testing but won't meet the needs of most real world users. So, our product focus needs to be on a solution that meets those expectations (Web & Full Stack).

Scott Reed
Scott Reed Aug 17, 2022 09:18 AM

Great, thank you for the update and great work :-)

Please login to comment.
Latest blogs
A day in the life of an Optimizely OMVP - Introducing the beta of Opti Graph Extensions add-on

Introducing Opti Graph Extensions: Enhanced Search Management for Optimizely CMS I am excited to announce the beta release of **Opti Graph...

Graham Carr | Sep 15, 2025

Content modeling for beginners

  Introduction Learning by Doing – Optimizely Build Series  is a YouTube series where I am building  a fictional  website called  TasteTrail , food...

Ratish | Sep 14, 2025 |

A day in the life of an Optimizely OMVP - Enhancing Search Relevance with Optimizely Graph: Synonyms and Pinned Results

When building search experiences for modern digital platforms, relevance is everything. Users expect search to understand their intent, even when...

Graham Carr | Sep 14, 2025

Optimizely CMS and HTML validation message: Trailing slash on void elements has no effect and interacts badly with unquoted attribute values.

When using the W3C Markup Validation Service, some annoying information messages pop up because Optimizely CMS adds the trailing slash to...

Tomas Hensrud Gulla | Sep 14, 2025 |