Optimizely and .NET 5 - the need for speed

November 23, 2021
5 minute read

In the same competitive spirit as Formula One teams who design and build a new car from scratch every year, Optimizely recently announced the release of Content Cloud 12 and Commerce Cloud 14. In the quest for a speed and performance advantage, it’s what they must do to stay competitive.

This is a significant milestone for Optimizely, building on a journey Microsoft began in 2014 to reimagine the .NET framework. This was eventually released as .NET 5 and is fundamentally different from its .NET framework predecessors, with an architecture geared to extreme-performance and cross-platform portability.

Sounds great - but what’s the benefit?


Your website will be significantly faster. Optimizely reports up to 10x speed improvements while Microsoft benchmarks place .NET 5 as the most performant web framework out there. Page speed is a vital factor in customer conversion rates, satisfaction and SEO, so a 10x jump will give you a step-change improvement.


Your site will be cheaper to run. .NET 5 apps are portable and can be executed on any type of device or operating system. You can now host your Optimizely sites on Linux, eliminating Windows licensing costs. Coupled with the speed improvements you’ll have a more efficient use of computation time. A win-win for consumption-based hosting models.


Optimizely have redesigned the administration interface, giving better views on scheduled integration tasks and providing overall cosmetic, experience and speed improvements across all functions.

Getting there

This is a major release, although Optimizely’s investment in a continuous release cadence means that practically speaking, the upgrade is similar to a minor version upgrade, albeit more involved - particularly if you intend to migrate to a Linux hosting environment.

A major upgrade always requires careful planning and consideration, but upgrading your Optimizely platform to take advantage of .NET 5 is not complex. Optimizely have been a primary contributor to Microsoft’s .NET 5 upgrade assistant which automates many of the boilerplate upgrade tasks. Testing and regression forms the majority of the effort.

In a fast-moving digital world, it’s vital that you keep your critical applications up-to-date and supported. A move to .NET 5 will also deliver key cost and performance advantage for your Optimizely Digital Experience stack.