Timestamp
Timestamp is a countdown app where every countdown is a URL. Pick a date, choose a theme, add a message — your countdown gets a unique link that works for anyone who opens it. Pure client-side magic.
Use Cases & Countdown Modes
| Use Case | Mode | Description | Try It |
|---|---|---|---|
| 🎆 New Year’s Eve with friends | 🏠 Local Time | Counts down to midnight in each viewer’s timezone | New Year 2027 |
| 🚀 Product launches | 🌐 Same Moment | Everyone sees the same countdown to an exact UTC instant | Launch Day |
| ☕ Meeting breaks | ⏱️ Timer | Quick countdowns for time-boxed activities | 5 Minutes |
Features
- Instant URL Sharing: Every configuration generates a shareable URL that updates automatically
- Progressive Web App: Install from your browser for offline support, full-screen mode, and automatic updates
- World Map: Wall-clock mode shows a day/night map with real-time solar position
- Multiple Themes: Choose from beautiful themes including GitHub contribution graph style and dynamic fireworks
- Accessibility: Full keyboard navigation, screen reader support, and reduced motion options
Related Content
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GitHub
Chris showcases Timestamp, an open-source countdown timer app built with vanilla TypeScript featuring an extensible theme system, world map wall clock, and 2500+ unit tests with 300+ Playwright end-to-end tests. He deep-dives into structuring GitHub Copilot custom instructions vs agents vs prompt files, demonstrates manager-specialist agent patterns, and walks through GitHub Actions automation for issue forms and theme scaffolding.
Rubber Duck Thursdays - Let's build our way into 2026!
GitHubChris builds a New Year countdown app from scratch using Vite, TypeScript, and Tailwind CSS, leveraging GitHub Copilot's Plan agent for iterative requirements and a custom UI Performance Specialist agent. The stream covers adding time zone support with a world map, a fireworks celebration theme using fireworks.js, and a test-driven development approach.
Rubber Duck Thursdays - Let's build with custom agents
GitHubChris dives into Copilot custom agents and custom instructions for the turn-based game MCP server project. After reviewing the changelog including enterprise bring-your-own-key support and Claude Opus 4.5, he restructures copilot-instructions.md, creates meta instruction files for writing instructions and agents, and explores plan mode for iterating on agent designs.