Timit

@vielzeug/timit is a Temporal-first date/time library for TypeScript. It provides ergonomic helpers for parsing, timezone conversion, arithmetic through DST transitions, and Intl-based formatting—without the fragility of native Date.

Installation

pnpm

pnpm add @vielzeug/timit

npm

npm install @vielzeug/timit

yarn

yarn add @vielzeug/timit

Quick Start

import { d } from '@vielzeug/timit';

// Get current time in a timezone
const meeting = d.asZoned(d.now(), { tz: 'America/New_York' });

// Add time (DST-safe)
const reminder = d.add(meeting, { minutes: -15 });

// Format for humans
const text = d.format(reminder, { pattern: 'short', locale: 'en-US' });

Why Timit?

Manual date handling breaks at daylight-saving boundaries, timezone edges, and DST transitions.

// Before — fragile, loses timezone context
const reminder = new Date(meeting.getTime() - 15 * 60_000);

// After — DST-safe, handles transitions correctly
const reminder = d.add(meeting, { minutes: -15 });

Feature	Timit	date-fns	Day.js	Native Date
Bundle size	1.0 KB	~10 kB	~3 kB	0 kB
DST-safe math	✅ (Temporal)	Manual	Manual	❌
Timezone aware	✅ Full support	✅	✅	Partial
Immutable	✅	✅	✅	❌
Format presets	✅ ('short', 'long', etc.)	❌	❌	❌
Type inference	✅ Full TypeScript	Partial	Partial	❌

Use Timit when you need reliable timezone handling, DST-safe arithmetic, and clean Temporal-based APIs without heavy dependencies.

Consider alternatives when you need extensive locale data (date-fns).

Features

• d namespace — grouped functions for IDE autocomplete (like Validit's v)
• DST-safe arithmetic — d.add(), d.subtract() handle transitions correctly
• Timezone conversion — d.asZoned(), d.asInstant() with full timezone support
• Preset formatting — 'short', 'long', 'iso', 'date-only', 'time-only'
• Range queries — d.within() for inclusive time range checks
• Duration diffs — d.diff() with granular control over units
• Intl integration — formatting respects locale & calendar systems
• Tree-shaking friendly — import d or individual functions
• Polyfilled Temporal — works in runtimes without native support via @js-temporal/polyfill
• 1.0 KB gzipped

Compatibility

Environment	Support
Browser	✅
Node.js	✅
SSR	✅
Deno	✅

See Also

• Usage Guide
• API Reference
• Examples
• Validit — Schema validation (similar v namespace pattern)
• Logit — Structured logging