COMPATIBILITY

Compatibility

Supported Runtime Environments

This package supports the following runtime environments:

• Node.js 20.x, 22.x, 24.x, 26.x
• Bun 1.2.x

Module format (v5)

umt v5 is ESM-only ("type": "module"). The package exports map exposes import and types only — there is no require condition, and the CommonJS / Babel build was removed.

import { chunk, isBetween } from "umt";
import { isBetween as isBetweenDate } from "umt/Date";

// No longer supported
const { chunk } = require("umt");

Subpath exports match source modules (umt/Array, umt/Date, umt/Validate, …). Tree-shaking follows those ESM entry points.

Input validation is the caller's responsibility. Functions do not throw on invalid arguments unless throwing is the function's purpose (for example unwrap).

IP helpers (umt/IP) are IPv4 only. TypeScript does not validate dotted-decimal strings; the Python and Rust ports raise / return Err on malformed addresses and reject non-contiguous subnet masks. isPrivateIp is RFC 1918 only (not loopback or link-local).

Versioning

This package follows Semantic Versioning (SemVer):

• MAJOR version: Breaking changes that may require code updates
• MINOR version: New features that are backward compatible
• PATCH version: Bug fixes that are backward compatible

Backward compatibility is maintained within the same major version.