Metaclasses underlie Python classes, enabling customization of class creation, but custom metaclasses are only appropriate when simpler techniques cannot achieve the goal.
Pattern matching encodes data shape in the type system, eliminating brittle imperative branching and improving correctness in domain-driven systems like digital commerce.
Experiment: making TypeScript immutable-by-default
TypeScript cannot be made immutable-by-default purely through its type system; arrays and Records can be made immutable, but regular objects remain problematic.
