npm i @koalarx/utils

TypeScript utilities for the Koala ecosystem

Masks, dates, arrays, and conversions — with fluent operators on the front and prototypes on the back.

What is @koalarx/utils?

A small, typed library for everyday TypeScript/JavaScript problems.

Typed core

KlString, KlNumber, KlDate, KlTime, and KlArray extend native types with fluent APIs.

Operators on the frontend

Import only what you need: format(date).split('/') without polluting prototypes.

Prototypes on the backend

One import in main and "123".maskCpf() anywhere in the process.

Opt-in holidays

date-holidays only loads when you import @koalarx/utils/holidays.

Four ways to use it

Pick class, primitive function, operators (FE), or prototypes (BE) for your context.
bash
npm i @koalarx/utils

Tree-shakeable

Per-module subpaths and named operators for smaller front-end bundles.

Chaining

KlString.split returns KlArray — clearEmptyValues and orderBy in the same flow.

Brazil first

CPF, CNPJ, currency, and time zones common in BR apps.

AI ready

llms.txt index and per-page Markdown — copy the URL into your assistant.

Global index

Use Copy AI in the header to copy https://utils.koalarx.com/llms-en.txt.

Page-level context

Use Copy for AI on each page for that topic's .md URL.