Xamarin Release Cycles

There are four major components of Xamarin's platform product: the Android SDK, the iOS SDK, our Xamarin Studio IDE and our Visual Studio extension.

In the past, we used to release each component independently, but last year we realized that developing and testing each component against the other ones was getting too expensive, too slow and introduced gratuitous errors.

So we switched to a new style of releases where all the components ship together at the same time. We call these cycles.

We have been tuning the cycle releases. We started with time-based releases on a monthly basis, with the idea that any part of the platform that wanted to be released could catch one of these cycles, or wait for the next cycle if they did not have anything ready.

While the theory was great, the internal dependencies of these components was difficult to break, so our cycles started taking longer and longer.

On top of the cycles, we would always prepare builds for new versions of Android and iOS, so we could do same-day releases of the stacks. These are developed against our current stable cycle release, and shipped when we need to.

We are now switching to feature-based releases. This means that we are now waiting for features to be stable, with long preview periods to ensure that no regressions are introduced.

Because feature based releases can take as long as it is needed to ship a feature, we have introduced Service Releases on top of our cycles.

Our Current Releases

To illustrate this scenario, let me show what our current platform looks like.

We released our Cycle 5 to coincide with the Build conference, back in April 29th. This was our last timed release (we call this C5).

Since then we have shipped three service releases which contain important bug fixes and minor features (C5-SR1, SR2 and SR3), with a fourth being cooked in the oven right now (C5-SR4)

During this time, we have issued parallel previews of Android M and iOS 9 support, those are always built on top of the latest stable cycle. Our next iOS 9 preview for example, will be based on the C5-SR4.

We just branched all of our products for the next upgrade to the platform, Cycle 6.

This is the cycle that is based on Mono 4.2.0 and which contains a major upgrade to our Visual Studio support for iOS and plenty of improvements to Xamarin Studio. I will cover some of my favorite features in Cycle 6 in future posts.

Posted on 01 Sep 2015 by Miguel de Icaza
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