Functional Programming Library

A practical functional programming library for JavaScript programmers, currently at version 0.32.0, designed specifically for a functional programming style rather than being a general-purpose utility toolkit. The library emphasizes a purer functional style where immutability and side-effect free functions are at the heart of its design philosophy, enabling developers to build elegant code through function composition rather than imperative mutation. All functions are automatically curried, meaning any function can be called with fewer arguments than it expects, returning a new function that waits for the remaining arguments, allowing easy partial application and function reuse without explicit bind or curry calls. Parameters are deliberately arranged so that the data to be operated on is generally supplied last, making it natural to build function pipelines where data flows left-to-right through composed transformations. The library provides over 250 functions covering array operations including map, filter, reduce, flatten, groupBy, and chunk; object operations including prop, path, merge, pick, and omit; function composition including compose, pipe, converge, and useWith; logic operations including both, either, complement, and allPass; and type checking including is, isNil, isEmpty, and propIs. Data is never mutated, with all operations returning new values rather than modifying inputs, preventing subtle bugs from shared mutable state. The library works with plain JavaScript objects and arrays as its core data structures, without introducing new data types or abstractions, keeping the learning curve low. Performance is prioritized alongside functional purity, with optimized implementations that avoid unnecessary intermediate allocations. The library runs in Node.js, Deno, browsers via CDN, and supports both CommonJS and ES module imports with tree-shaking.