I replaced one type of Future for another in a large Java codebase. Not productive. I had a colleague who wanted to rewrite the same piece of code using Obser

I replaced one type of Future for another in a large Java codebase. Not productive. I had a colleague who wanted to rewrite the same piece of code using Observables instead. Later in a different company I met someone who was working on the exact opposite, i.e. taking Observable code and rewriting it as Futures because "observables are confusing". Just extract these things behind an interface and call it a day.