Does this skill support timezone-sensitive applications?

Yes, it includes patterns for both date-fns-tz (v3) and the newer @date-fns/tz (v4) including TZDate to handle complex timezone conversions and DST.

Can I use this for internationalization (i18n)?

Absolutely. It provides patterns for locale-aware format shortcuts that automatically adapt to regional date and time conventions based on the provided locale.

Why use parseISO instead of the native Date constructor?

The native Date constructor is notoriously inconsistent across different browsers when parsing strings; parseISO provides a predictable, standard-compliant way to parse ISO 8601 strings.

How does this skill help with application performance?

It enforces modular imports of specific date-fns functions, allowing modern build tools to tree-shake unused code and keep the final bundle size as small as possible.

Date-Fns Web Utilities

Name: Date-Fns Web Utilities
Author: agents-inc

byagents-inc

•

Developer Tools

Provides standardized date-fns patterns for TypeScript, ensuring immutable, tree-shakeable, and locale-aware date manipulation.

This skill equips Claude with specialized patterns for the date-fns library, focusing on modern TypeScript development for versions 3 and 4. It enforces high-performance best practices such as safe ISO parsing to avoid browser inconsistencies, modular imports to optimize bundle sizes, and immutable date arithmetic to prevent side-effect bugs. The skill covers a wide range of utilities from basic formatting and semantic comparisons to complex timezone handling with @date-fns/tz and internationalization using locale-aware shortcuts.

Key Features

01Comprehensive timezone handling for modern v4 TZDate and legacy v3 patterns.

02Tree-shakeable import patterns that significantly reduce application bundle size.

031 GitHub stars

04Locale-aware formatting shortcuts (P, PP, PPP) for seamless internationalization.

05Safe ISO 8601 parsing using parseISO to prevent cross-browser date bugs.

06Immutable date arithmetic and manipulation using pure functional programming.

Use Cases

01Generating consistent date ranges and boundaries for database filters and calendar UIs.

02Building internationalized web applications requiring localized date and time displays.

03Implementing complex date arithmetic for billing cycles, trial periods, or scheduling.

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add agents-inc/skills web-utilities-date-fns

For use in Claude.ai and ChatGPT

Key Features

01Comprehensive timezone handling for modern v4 TZDate and legacy v3 patterns.

02Tree-shakeable import patterns that significantly reduce application bundle size.

031 GitHub stars

04Locale-aware formatting shortcuts (P, PP, PPP) for seamless internationalization.

05Safe ISO 8601 parsing using parseISO to prevent cross-browser date bugs.

06Immutable date arithmetic and manipulation using pure functional programming.

Use Cases

01Generating consistent date ranges and boundaries for database filters and calendar UIs.

02Building internationalized web applications requiring localized date and time displays.

03Implementing complex date arithmetic for billing cycles, trial periods, or scheduling.

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add agents-inc/skills web-utilities-date-fns

For use in Claude.ai and ChatGPT