Pref Support Now Available in Nimbus

[Jared Kerim]

Hi everyone,

I want to share an exciting update from Nimbus: we now support remotely setting prefs! 

This will allow you to run experiments and rollouts against any number or combination of prefs, on either the default or user branch, by first declaring them as a Feature in the Desktop Nimbus Feature Manifest, and then defining and launching your experiment or rollout in Experimenter.

For those that have used Normandy in the past, many elements of this will be familiar, but unlike Normandy, Nimbus experiments and rollouts can be run entirely independently by anybody at Mozilla without requiring sign offs or fixed schedules or special operators.  Anybody can become a Nimbus reviewer by following these steps.  Nimbus pref experiments and rollouts also receive all of our automated monitoring and analysis capabilities. 

Adding support for prefs in Nimbus is the next step in our plan to deprecate Normandy.  We are now entering Phase 2 in the migration plan.  This means that many pref experimentation and rollout needs can be transitioned to Nimbus, and for those that are unable to use Nimbus, particularly around remotely setting prefs on very short notice where there is not time to declare them in the manifest, Normandy is still fully available and supported.  We will monitor the adoption of pref support in Nimbus and any continued dependence on Normandy and evaluate how we can best support any remaining use cases.

Please feel free to ask any questions or provide feedback in #ask-experimenter on Slack, or reach out to me directly.  We're looking forward to seeing all of your pref experiments and rollouts this year!

Jared Lockhart

Engineering Lead, Nimbus