Immutable.js
Immutable.js is a JavaScript library developed by Facebook that provides persistent immutable data structures, such as Lists, Maps, Sets, and Records. It ensures that data cannot be modified after creation, instead returning new updated collections, which helps prevent accidental mutations and side effects in applications. This library is particularly useful in functional programming paradigms and state management scenarios where predictability and performance are critical.
Developers should learn and use Immutable.js when building applications that require predictable state management, such as in React or Redux-based projects, to avoid unintended side effects and improve performance through structural sharing. It is especially valuable in large-scale applications where managing complex state changes efficiently is necessary, as it provides optimized data structures that reduce memory usage and enhance rendering performance by enabling shallow equality checks.