Zero runtime dependencies

Nothing but the platform. No Lodash, no qs, no deepmerge — enforced by a CI check on every build.

Tree-shakeable by design

One function per file and sideEffects false. Importing chunk ships 0.20 kB gzipped, not a library.

Immutable everywhere

No exported function mutates its input, so reference equality checks in Vue, React and Svelte stay correct.

TypeScript-first

Written in strict TypeScript. Types are generated from the source — no @types package, no any in the public API.

ESM and CommonJS

A modern exports map with per-condition types, verified by typechecking real ESM and CJS consumer projects in CI.

Per-function imports

import chunk from 'modern-fns/array/chunk' resolves to exactly one module, no barrel file in the way.

Install

bash

npm install modern-fns

import { groupBy, set, diff, slugify, currency } from 'modern-fns';

groupBy(orders, 'status'); // { paid: [...], pending: [...] }
set(state, 'user.address.city', 'Kochi'); // immutable — `state` untouched
diff(pristine, form); // [{ path: 'name', type: 'changed', ... }]
slugify('Hello Vue World!'); // 'hello-vue-world'
currency(1299.5, 'INR', 'en-IN'); // '₹1,299.50'

Ten focused modules

Module

What it covers

array

chunk, unique, groupBy, indexBy, partition, sortBy, orderBy, zip, range, diffArray

object

get, set, has, unset, pick, omit, deepClone, deepMerge, isEqual, flattenObject

diff

structural diffs for dirty checking, audit logs, PATCH bodies and undo/redo

string

slugify, camelCase, kebabCase, truncate, initials, mask, stripHtml, isEmail

number

clamp, decimal-safe round, percentage, formatNumber, abbreviate, currency, tax

url

parseUrl, buildUrl, setQuery, mergeQuery, removeHash, joinUrl, isSameUrl

query

parse, stringify, get, set, toggle, parseArray — a dependency-free qs alternative

value

toNumber, toBoolean, toDate, toArray plus typed guards for untrusted input

functional

pipe, compose, debounce, throttle, memoize, once, tryCatch, tap

collection

one iteration API across arrays, objects, Map, Set and iterables

Why not just use Lodash?

Lodash predates ES modules, TypeScript-by-default and bundle-size budgets. modern-fns is built for those constraints: native ESM with an exports map, types generated from the source rather than a separate @types package, and immutability as a rule rather than a per-function detail.

The full comparison is honest about where Lodash is still the better choice.

modern-fnsModern JavaScript utility library