Timestamp is a small TypeScript library for working with immutable date and time objects.

It is not tied to a UI framework, backend framework, or application platform. You can use it in browser apps, Node.js services, SSR applications, static-site builds, tests, and framework-specific libraries.

Design goals

• Framework agnostic: works with Vue, React, Svelte, plain TypeScript, Node.js, and other JavaScript runtimes.
• Immutable by default: parser and update helpers return frozen Timestamp objects.
• Calendar-friendly: date strings, weekday metadata, day-of-year, workweek, interval generation, and range comparison are first-class.
• Runtime-safe: no dependency on window, document, storage APIs, or framework state.
• Small core: deterministic primitives without full date-library scope.

Basic example

import { addToDate, getDateTime, parseTimestamp } from '@timestamp-js/core'

const start = parseTimestamp('2026-06-08T09:30:15.250Z')
const end = start ? addToDate(start, { day: 2, minute: 45 }) : null

console.log(end ? getDateTime(end) : 'Invalid date')

What Timestamp is not

Timestamp is not trying to replace every date library. It does not currently provide full timezone conversion, duration formatting, relative phrase formatting, or non-Gregorian calendar systems.