modern-javascript-patterns

Convert callbacks to async/await by replacing nested callback functions with async functions and await expressions. This modernizes asynchronous code, improves readability, and reduces callback nesting while maintaining the same execution flow.

ES6 modules organize code into reusable files using import/export syntax instead of globals or bundled scripts. They provide better dependency management, namespace isolation, and enable tree-shaking for smaller production builds.

Replace var with const/let, use arrow functions, apply destructuring for object/array extraction, leverage spread/rest operators, and adopt functional patterns like map/reduce. These changes improve maintainability, reduce bugs, and align with modern tooling.

Promises chain asynchronous operations using .then(); async/await wraps Promises in a synchronous-looking syntax. Async/await is cleaner and easier to debug, while Promises remain useful for parallel operations and error chains.

Arrow functions and destructuring require ES6+ support or transpilation via Babel. If targeting legacy browsers, transpile your code to ES5 or use polyfills, though most modern projects support ES6+ natively.

Use generators for lazy evaluation, state management, and producing sequences on-demand. Iterators enable custom looping logic and reduce memory overhead compared to creating full arrays upfront.