[dgb23]

I fully agree with the first. You usually need some designed way of handling communication and/or IO in a sufficiently large application. Whether these are event queues, channels, commands, pipelines or w/e depends. But thinking about this up-front is the key here.

I would describe the second as a constraint rather than an abstraction. And I fully agree with this. The most obvious and probably most talked about benefit of FP would be avoiding state management complexities.

The third one is neat. But I would say we're already in danger territory here. Just writing a function and naming it properly is the minimal step required to make refactoring into a strategy or plugin pattern later fairly straightforward.