Rules are a nice addition to submicroflows, as you don’t have to evaluate the outcome of a MF (e.g. i always use the IsNotEmptyString rule from the community commons), there it is really frustrating to not have them available in Nanoflows. Why not create rules that can be used in Nanoflows?
A bit similar to my idea, 'Call nanoflow' activity in microflow, in essence: you want reusable logic in both microflows and nanoflows, Eline called it a "Flexiflow", you call it a Rule 😁. The problem is that expressions could be evaluated differently in Java vs. JavaScript; but as not-so-tech-savvy person, you don't want to be bothered by that stuff and just reuse your rules and flexiflows in both nanoflow and microflows.
Confusingly, Mx Studio Pro (10.18.0) does allow to include Rule-based decisions in a Nanoflow. They are included in the options provided by the nanoflow activity recommender and are inserted when selected.