GoKawiilNew take on Gary Bernhardt's 'Functional Core' model reframes it around determinism
A technical essay revisits Gary Bernhardt's decade-old 'Functional Core, Imperative Shell' architecture, arguing that the key property enabling easy testing isn't functional purity itself but determinism. The author suggests that state machines and other deterministic constructs can achieve the same testability benefits as pure functions, broadening how developers might structure isolated, predictable 'core' logic versus the messier, IO-heavy 'shell' that talks to the outside world.