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A countdown app where every countdown is a URL. Create custom countdowns, timers, and world clocks for any occasion with multiple visual themes and instant URL sharing.

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.

Quoted as a GitHub expert on the importance of integrating security tooling into development lifecycle and the role of AI in secure coding practices.

Chris 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.

Chris reviews the latest GitHub changelog including CodeQL updates, GPT-5.1 Codex Max preview, GitHub MCP server tool-specific configuration, and Enterprise Server 3.19 GA. He then explores the major VS Code December release featuring Agent HQ, background agents with git worktrees, sub-agents, and custom agents for organizations, while continuing to build custom agents for a game MCP server project.

Chris continues building custom agents for the software development life cycle. After reviewing the changelog including Copilot Spaces updates and assigning issues to Copilot via API, he explores the awesome-copilot repository for agent inspiration, brainstorms SDLC agent ideas like test writers and security reviewers, and live-builds a GitHub Actions workflow agent with a companion instructions file.

Chris 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.

Chris catches up on several weeks of GitHub releases, including new models including GPT-5.1, GPT-5.1 Codex, and GPT-5.1 Codex Mini, MCP registry controls, and isolated sub-agents. He then returns to the turn-based game MCP server project, using Copilot's agent mode to diagnose and fix a dependency upgrade failure.

I've been exploring ways to bring social engagement into my blog posts. Taking inspiration from Ashley Willis' implementation, I've integrated Bluesky comments and likes into my Hugo site using the AT Protocol's public API.

In this live stream, we explore building a 3D tic-tac-toe visualization using Three.js and Copilot coding agent, demo MCP elicitation for gathering game preferences, and discuss the importance of context engineering when working with AI tools. We also cover GitHub changelog highlights including path-scoped custom instructions for Copilot code review and agents.md support.