Let's Create a GitHub Copilot Extension! - Nick Taylor, Pomerium
Presented at All Things Open AI 2025 Presented by Nick Taylor - Pomerium Title: Let's Create a GitHub Copilot Extension! Abstract: Get hands-on in this talk where we'll create a GitHub Copilot Extension from scratch. We'll use the Copilot Extensions SDK, https://github.com/copilot-extensions/preview-sdk.js, and Hono.js, covering best practices like payload validation and progress notifications and error handling. We'll also go through how to set up a dev environment for debugging, including port forwarding to expose your extension during development as well as the Node.js debugger. By the end, we'll have a working Copilot extension that the audience can try out live. Find more info about All Things Open: On the web: https://www.allthingsopen.org/ Twitter: https://twitter.com/AllThingsOpen LinkedIn: https://www.linkedin.com/company/all-things-open/ Instagram: https://www.instagram.com/allthingsopen/ Facebook: https://www.facebook.com/AllThingsOpen Mastodon: https://mastodon.social/@allthingsopen Threads: https://www.threads.net/@allthingsopen Bluesky: https://bsky.app/profile/allthingsopen.bsky.social 2025 conference: https://2025.allthingsopen.org/
Let's Create a GitHub Copilot Extension! - Nick Taylor, Pomerium
- 1. Let’s Create a GitHub Copilot Extension
- 2. About Me • Developer Advocate at Pomerium • From Montreal, Quebec, Canada • I’m @nickytonline everywhere • All the places you can find are on nickyt.online • Not a big fan of spiders
- 4. ● What is GitHub Copilot? ● What is a GitHub Copilot Extension? ● The anatomy of a Copilot Extension What We’ll Cover
- 5. ● Let’s Build! ○ Grab the nickytonline/copilot-extension-template template repository ○ Copilot Extension SDK Preview ○ Getting Your Dev Environment Set Up ● Wrapping Up What We’ll Cover
- 7. Story Time
- 11. If you want to follow along with the demo later, pull down this template repository nickytonline/copilot-extension-template
- 12. What is GitHub Copilot?
- 13. GitHub Copilot is a coding assistant, your pair programming buddy ● Can perform inline code completions ● Has chat capabilities to ask questions, get answers and refactor files ● Can be extended via GitHub Copilot Extensions ● Has a new agent mode as of early February 2025 What is GitHub Copilot?
- 14. GitHub Copilot can now be used in any editor if they leverage the recently released Copilot Language Server SDK What is GitHub Copilot?
- 15. Where can you use Copilot? ● Microsoft development environments and properties ○ GitHub.com ○ Visual Studio ○ Visual Studio Code ○ GitHub Codespaces What is GitHub Copilot?
- 16. Where can you use Copilot? ● JetBrains IDEs ● XCode ● Vim/Neovim ● Any editor that leverages the Copilot Language Server SDK What is GitHub Copilot?
- 17. You can even use GitHub Copilot on the command line now What is GitHub Copilot?
- 18. What is a GitHub Copilot Extension?
- 19. The name says it all. It literally extends GitHub Copilot ● Create custom AI-powered tools ● Integrate with third-party services ● Can access files and editor context What is a GitHub Copilot Extension?
- 20. Two types of Copilot Extensions: 🧰 Skillset: makes it easier to connect third-party services and custom APIs into the Copilot workflow 🤖 Agent: provides complete control over request handling and response generation, enabling custom workflows through integration with LLMs and APIs while managing conversation context and user interactions. What is a GitHub Copilot Extension?
- 21. An extension works anywhere GitHub Copilot is available except for the command line. What is a GitHub Copilot Extension?
- 22. If calling a Copilot extension that is an agent, your prompt must start with @copilot-your-extension-name What is a GitHub Copilot Extension?
- 23. The anatomy of a Copilot Extension
- 24. Two things are required to create a Copilot extension: ● A publicly accessible web application ● A registered GitHub application The anatomy of a Copilot Extension
- 25. Permissions to set for the GitHub App ● Access to a user’s Copilot chat (read-only and required) ● Access to context (read-only and optional) The anatomy of a Copilot Extension
- 26. The anatomy of a Copilot Extension
- 27. Let’s Build! 🏗
- 28. Pull down this template repository nickytonline/copilot-extension-template
- 30. Getting Your Dev Environment Set Up
- 31. ● Install the dependencies for the project ● Expose local development server to the Internet ● Create and configure a GitHub Application Getting Your Dev Environment Set Up
- 32. ● Leverage the copilot-extensions/preview-sdk.js ● Debug extension Getting Your Dev Environment Set Up
- 33. Wrapping Up
- 34. ● Still early days for Copilot Extensions ● Expect a Cambrian explosion of Copilot extensions ● 2025 is the year or AI agents ● Go give nickytonline/copilot-extension-template a star ● Go build a GitHub Copilot extension! Wrapping Up
- 35. Resources
- 36. ● Official GitHub Copilot documentation ● nickytonline/copilot-extension-template ● Creating a GitHub Copilot Extension: A Step-by-Step Guide ● Building an Ollama-Powered GitHub Copilot Extension ● VS Code specific Copilot Extensions Resources
- 37. ● GitHub Open Source Spotlight: Building Copilot Extensions with Nick Taylor ● Building a Copilot skillset for your Copilot Extension ● Building a Copilot agent for your Copilot Extension ● GitHub Copilot: The agent awakens Resources
- 38. Slide Deck
- 39. That’s all folks! Thank you and stay in touch! ● @nickytonline everywhere ● nickyt.online