Practical techniques to reduce webpack bundle size and speed up builds: code splitting, tree shaking, and caching strategies.

Why browsers block cross-origin requests, how CORS works, and common solutions including proxy and JSONP.

The difference between MVC and MVVM patterns, and how Vue's data binding maps to the MVVM model.

A practical reference for common array methods: mutating vs non-mutating, iteration helpers, and real-world use cases.

What the Reflect object provides, how its methods mirror Proxy traps, and why it's the right way to forward operations inside a proxy.

A breakdown of Vue3’s compile-time optimizations: static hoisting, patch flags, block tree, and event handler caching.

How the call stack, task queue, and microtask queue interact to make JavaScript's single-threaded async model work.

The problem virtual DOM solves, how the diffing algorithm works, and why it doesn't always mean better performance.

How prototypal inheritance works in JS: the relationship between __proto__, prototype, and constructor.

What a Promise is, how the state machine works, and how to chain async operations with then, catch, and async/await.