From Copilot CLI to Cloud Agents: How Brittany Ellich Builds at GitHub

In this episode, I sat down with Brittany Ellich, Staff Engineer at GitHub, to talk about what software engineering looks like when AI is part of nearly every step of the workflow. We got into her path from a smaller medical education company to GitHub, what it means to work on enterprise billing and metered usage, and why billing systems are such a fascinating engineering problem: speed matters less than accuracy, and in distributed systems that’s a surprisingly hard thing to optimize for. We also explored how GitHub’s different cloud and enterprise offerings complicate that work, especially when data residency and product flexibility enter the picture. From there, we went deep on AI-assisted development: async vs. sync coding, delegating work to cloud agents, using GitHub Copilot CLI and VS Code in agent mode, and how tools like Spec Kit and SQUADS are changing the way features get planned and built. Brittany shared how AI has shifted her role toward product thinking, architecture, and review, and we talked honestly about trust, pride, technical debt, junior engineers, and where the profession may be heading next. It’s a thoughtful, grounded conversation about adapting to a fast-moving moment in software without losing the joy of building. Brittany Ellich website: https://brittanyellich.com/ GitHub: https://github.com/ Microsoft: https://www.microsoft.com/en-us GitHub Actions: https://github.com/features/actions GitHub Enterprise: https://github.com/enterprise GitHub Enterprise Server docs: https://docs.github.com/en/enterprise-server@3.17/admin/overview/about-github-enterprise-server GitHub Copilot: https://github.com/features/copilot GitHub Copilot CLI: https://github.com/features/copilot/cli GitHub Copilot CLI getting started docs: https://docs.github.com/copilot/how-tos/copilot-cli/cli-getting-started Visual Studio Code: https://code.visualstudio.com/ OpenAI Whisper: https://openai.com/index/whisper/ GitHub Spec Kit: https://github.com/github/spec-kit Spec Kit documentation: https://github.github.io/spec-kit/ SQUADS CLI: https://squads.sh/en/docs/cli CascadiaJS: https://cascadiajs.com/ Craig Dennis talk, “AIdentity Crisis: Can I be Proud of This?”: https://cascadiajs.com/2025/talks/aidentity-crisis-can-i-be-proud-of-this Hacker News: https://news.ycombinator.com/ Rust programming language: https://rust-lang.org/ React: https://react.dev/ Stack Overflow: https://stackoverflow.com/questions LeetCode: https://leetcode.com/ OpenAI: https://openai.com/ Gemma: https://deepmind.google/models/gemma/ Gemma 4: https://deepmind.google/models/gemma/gemma-4/ Anthropic Claude Mythos: https://www.anthropic.com/claude/mythos