About
This skill provides a robust framework for preventing systemic failures by applying the defense-in-depth principle to data validation. It guides developers to implement four distinct layers of protection: entry point validation, business logic verification, environment-specific guards, and debug instrumentation. By making bugs structurally impossible rather than just fixing them once, it ensures that refactors, mocks, or alternative code paths cannot bypass critical system integrity checks, leading to more resilient and maintainable codebases.
