Mastery

TypeScript · Expert - architecture, internals and edge cases

• Conditional types and infer: the compiler's logicMaster the distributivity of conditional types, pattern matching with infer, and edge cases like never, any, and boolean.
• Mapped types and key remapping: transforming typesUnderstand how homomorphic mapped types preserve modifiers and how the as clause renames or filters keys.
• Template literal types: strings computed at compile timeLeverage template literal types to generate unions through Cartesian products and parse string literals with infer.
• Overloads, typed this, and varianceUnderstand overload resolution, the this pseudo-parameter, and the variance rules that govern function assignability.
• Production patterns: branded types, satisfies, and .d.tsApply the expert patterns that secure a real codebase: simulated nominality, validation without widening, and ambient declarations.