Area Before (JavaScript) After (Angular and TypeScript)
Data-shape defects Detected in production, after reaching end usersIdentified at compile time, prior to release
Engineering effort Substantial time devoted to diagnosing runtime errors Effort reallocated toward feature development
Release stability Each deployment carried unpredictable risk Controlled, gated releases with fewer incidents
Developer onboarding Dependent on undocumented, informal knowledge Types serve as reliable, self-documenting contracts
RefactoringMinor changes introduced considerable uncertainty Supported by the compiler, reducing regression risk
ScalabilityAdditional data sources and widgets increased fragility New sources and widgets integrated with confidence