JavaScript Coding Patterns Questions

Common and modern JavaScript coding patterns used to build maintainable, testable, and performant front end code. Topics include modern language features such as arrow functions, the spread operator, and destructuring, patterns for asynchronous code using promises and async await, functional programming idioms like immutability and composition, module and factory patterns, and robust error handling practices. Candidates should also discuss when to apply these patterns and trade offs between clarity and micro optimization.