TFS 2018–XAMLs back?!?

Starting in TFS 2017 it was announced that XAML builds were being deprecated. No big surprise to anyone paying attention as they are an older build system which had to go at some point. However this was a HUGE blocker for alot of customers who want to upgrade but don’t/can’t invest the time to switch hundreds of build definitions from XAML to Task based. Now (due to customer feedback) it’s been decided to deprecate XAML builds but leave the functionality in there. I think its a great compromise…letting our legacy customers get the new features while not permitting them from upgrading directly.

In one of his recent blog posts Brian Harry describes in great detail the reasoning behind this deprecation and why it had to be done. He mentions that the XAML support will go away in VSTS by the end of 2018….one wonders if there might be built-in features to allow customers to continue to use XAML builds since TFS on-premise decided to “bring it back”.

In his own words:

We first introduced basic build automation capabilities in TFS 2005 and, over the years, it has evolved substantially.  In TFS 2010, we introduced a major update which we now call “XAML build” because the build orchestration layer was based on the XAML workflow engine.  As that got adopted, we found that workflow was just not the best representation of build processes – wrong granularity for build, not natural to extend for build, provides capabilities (like durability) that really don’t apply to build, etc.  And, as we began to stretch beyond .NET/Windows into Mac, Linux, etc., it became clear that Windows Workflow was not the right foundational technology.  In TFS 2015, we shipped another major update, introducing a simpler, cross platform pipeline/task model.

Because the two models are so different, we have supported both in parallel to allow customers to continue to work (and even upgrade to new version of TFS) without interruption.  By supporting both, in parallel, people have time to try out the new version, learn it and, where appropriate, adopt/migrate to it.  We feel (and evidence based on usage shift) that the new build system is in good shape and ready for broad adoption.

The plan has been, and continues to be, to remove support for the XAML based build system from a future version of TFS and Team Services.  I want to share where we are on that journey and what lies ahead.  We know deprecating existing capabilities is painful and we never do it lightly.  Unfortunately, we do need to make breaking changes from time to time and we try hard to make it as smooth as possible.  Feedback is always welcome on how we could do it better.

Personally I think it’s a brilliant move to satisfy large customers. It show-cases how Microsoft continues to innovate and pivot as much as possible based on our customer’s feedback.