any vs unknown vs never (Interview-Ready)
How to choose any/unknown/never, why unknown is safer, and how never appears in narrowing and exhaustive checks.
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Event loop, closures, this, hoisting, async, and the fundamentals interviews test.
Types vs interfaces, narrowing, generics, utility types, and practical TS patterns.
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A practical, interview-focused guide to the JS event loop: call stack, Web APIs, task queues, microtasks vs macrotasks, and common trick questions with real examples.
A deep, interview-ready guide to TypeScript types vs interfaces: extension, unions, intersections, declaration merging, and practical patterns for real codebases.
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Results
How to choose any/unknown/never, why unknown is safer, and how never appears in narrowing and exhaustive checks.
A deep, interview-ready guide to TypeScript utility types: Pick/Omit/Partial/Required/Readonly/Record, common patterns, and how to avoid over-complicating types.
A deep, interview-ready guide to narrowing in TypeScript: typeof, in, instanceof, user-defined type guards, and discriminated unions for safe, expressive code.
A deep, interview-ready guide to TypeScript generics: why they exist, how inference works, constraints (extends), default generics, and practical examples used in real codebases.
A deep, interview-ready guide to TypeScript types vs interfaces: extension, unions, intersections, declaration merging, and practical patterns for real codebases.
A deep, interview-ready guide to frontend testing: what to test, unit vs integration vs e2e tradeoffs, reliable patterns, and common anti-patterns.
A deep, interview-ready accessibility guide: semantic HTML first, ARIA rules, focus management, keyboard support, and common mistakes that break screen readers.
A deep, practical guide to Core Web Vitals for frontend interviews: what LCP/CLS/INP measure, common causes, how to debug in DevTools, and high-impact fixes.
A deep, practical guide to Service Workers: lifecycle, caching strategies (cache-first, network-first, stale-while-revalidate), offline support, and common pitfalls.