How should an architecture properly enforce module boundaries between different features, ensuring one feature genuinely does not develop an unwanted, tightly coupled direct dependency on another entirely separate feature's own specific internal implementation details?

Enforcing clean, genuinely healthy module boundaries between different features typically means each individual feature should only ever expose a small, deliberately minimal, clearly defined public interface, such as a few specific carefully chosen classes or a small number of navigation entry points, while deliberately keeping the vast majority of its own internal implementation details genuinely private and hidden from other unrelated features, and tools such as Dart's own custom lint rules, or genuinely separate internal packages entirely, as discussed previously, can help actively enforce this important separation, actively preventing an unwanted, tightly coupled dependency from silently and gradually creeping in over time as a large codebase continues to evolve.

// A feature exposes only a small, intentional public interface
export 'src/checkout_entry_point.dart';
// Internal implementation files remain unexported and effectively private