v0.0.0-beta.3
The 4× faster date library for JavaScript.
Ultra-fast, zero-dependency date manipulation with full Day.js API compatibility. Built for performance-critical applications with TypeScript-first design.
import { fdu } from "@pyyupsk/fdu";// Create a date instanceconst date = fdu("loading...");// Format with custom patterndate.format("dddd [at] HH:mm");// → "loading..."Built for modern JavaScript applications
Performance-first architecture with developer experience at its core.
4× Faster Performance
19.6M comparison operations per second. 13× faster comparisons, 6× faster chained operations than Day.js.
Zero Dependencies
100% self-contained TypeScript implementation. No bloat, no supply chain risks, minimal bundle size.
20+ Locales Built-in
Internationalization covering 4.3B+ speakers. Tree-shakeable locale files (300-500 bytes gzipped each).
Immutable by Default
Every operation returns a new instance, preventing subtle mutation bugs in your application.
TypeScript-First
Full IntelliSense support with strict type safety. No any types in public APIs.
98%+ Test Coverage
Rigorously tested with 20+ test files. CI pipeline on Node 20.x, 22.x, and 23.x.
Performance that speaks for itself
Benchmarked with Vitest 4.0.15 and Bun 1.3.3 on 2025-12-05 - Real-world performance gains for your applications.
| Operation | @pyyupsk/fdu | Day.js | date-fns | Luxon | vs Day.js |
|---|---|---|---|---|---|
| Date Parsing | 2.88M ops/sec | 2.06M ops/sec | 134.1K ops/sec | 413.1K ops/sec | 1.40× |
| Date Formatting | 955.1K ops/sec | 548.7K ops/sec | 398.0K ops/sec | 626.1K ops/sec | 1.74× |
| Date Manipulation | 3.87M ops/sec | 965.2K ops/sec | 3.28M ops/sec | 449.1K ops/sec | 4.01× |
| Date Comparison | 20.17M ops/sec | 1.53M ops/sec | 4.92M ops/sec | 6.98M ops/sec | 13.18× |
| Complex Workflow | 549.8K ops/sec | 245.9K ops/sec | 415.5K ops/sec | 143.1K ops/sec | 2.24× |
| Batch Operations (100 dates) | 9.4K ops/sec | 5.3K ops/sec | 5.7K ops/sec | 2.8K ops/sec | 1.79× |
Ready to get started?
Install @pyyupsk/fdu in your project and start building with modern date utilities.