Live Coding with Wes Bos, Burke Holland, Pierce Boggan & Friends | GitHub Copilot Day

GitHub hosts a two-hour live-coding session with Wes Bos, Burke Holland, and Pierce Boggan showing how GitHub Copilot can take a 3D foldable phone simulator from scratch to running functional web apps, including parallel agent workflows, model choices, and practical debugging in the browser.

Overview

A live build where the presenters create a 3D foldable phone simulator and get real web apps running inside it while using GitHub Copilot to iterate quickly.

Key themes covered in the session:

• Building the simulator experience (including an “exploded view” concept and rendering HTML inside a canvas)
• Using Copilot to iterate on UI and interaction details (pan/orbit controls, previews, and app rendering)
• Managing and steering long-running work while Copilot is generating changes
• Working with parallel AI agents and coordinating their output
• Choosing between different models and using multi-model options in the Copilot app
• Using built-in browser tools/flags to debug and unlock required capabilities

Links shared in the description

• Learn more about HydraFusion: https://gh.io/ghcpdayhydrafusion
• Get hands-on with the Copilot app: https://gh.io/ghcpdaycopilotapp
• Copilot app resources: https://gh.io/ghcpdaycopilotappresources
• Install GitHub Copilot CLI: https://gh.io/ghcpdaycopilotcli
• GitHub Copilot Dev Days: https://gh.io/join-dev-days

Session timeline (from the video description)

• 0:00 Welcome — two hours to build something
• 0:50 Introducing Wes Bos
• 1:36 The iPhone Duo 3D model backstory
• 2:52 The plan: exploded view + HTML in Canvas
• 3:16 First prompt: a knolling grid layout
• 4:28 What HTML in Canvas unlocks
• 5:42 Wes's HTML in Canvas skill
• 7:36 Steering the agent mid-loop
• 9:18 Matching the model to the task
• 10:07 Fixing pan and orbit controls
• 13:13 The calculator is taking too long
• 14:27 Adding a color picker and wallpapers
• 15:51 Hunting for the app preview
• 18:39 The calculator renders on the phone
• 19:48 Exploding the phone while the app runs
• 21:18 Wes hands off the challenge
• 22:56 Burke and Pierce take over
• 25:42 Blocked by the package proxy
• 27:22 Which models do you cook with?
• 29:15 New auto mode and optimization knobs
• 30:47 Why engineers pick one model and stay
• 33:14 Prompting a camera and photos app
• 34:03 Do you still plan? The prototype is the plan
• 35:32 Long-running agents and batching work
• 36:42 The camera app works on the first try
• 40:08 A GitHub app and an agent control plane
• 41:20 Why agents ask questions outside plan mode
• 43:25 Worktree, local, and cloud sessions
• 44:29 Why you'll need remote agents
• 46:04 Fanning out 50 sub-agents, one per app
• 48:20 Merging worktrees back to the main session
• 50:16 Designing for a foldable UI
• 51:44 The era of the idea
• 52:58 Anti-pattern: over-engineering your agent setup
• 54:07 Over-specified plans limit the model
• 55:44 Your local machine becomes the constraint
• 58:35 Agents writing their own acceptance tests
• 1:00:07 Why the web stack is winning for agents
• 1:01:19 Rubber-ducking and adversarial review
• 1:03:36 The GitHub app running on the simulator
• 1:05:52 Finally finding the right browser flag
• 1:10:22 Getting apps onto the 3D model
• 1:11:36 Telling the agent to stop adding apps
• 1:17:20 Computer use kicks in
• 1:22:00 Recap for anyone just joining
• 1:24:29 The GitHub app: repos, issues, and PRs
• 1:25:58 Apps finally render on the foldable
• 1:27:16 Designing for book, flat, and tent modes
• 1:31:02 Retained code: from 50% to 90%
• 1:32:32 When does everyone get this intelligence?
• 1:34:24 Do we still read the code?
• 1:35:30 The real bottleneck is your engineering system
• 1:37:24 Why reviewing every line isn't practical
• 1:39:21 Copilot SDK running inside the simulator
• 1:42:07 Pivot: an app store that builds on demand
• 1:43:18 How many AI credits did this cost?
• 1:44:04 Why max reasoning isn't always better
• 1:46:01 Is $25 an hour worth it?
• 1:47:36 How long this would have taken before
• 1:48:45 Saying no, and reading while the agent works
• 1:49:53 Isolation: multiple agents, multiple ports
• 1:51:23 Just ask Copilot to set up your machine
• 1:52:09 Nested sessions and the chief of staff pattern
• 1:54:06 Canvases that control the app
• 1:56:01 BYOK and why completions use custom models
• 1:57:28 The app store, live
• 1:58:32 Automations: daily dead code removal
• 2:00:12 Automations for meetings and message triage
• 2:02:12 Will apps be generated on demand?
• 2:03:43 Takeaways from GitHub Copilot Day
• 2:06:22 Wrap-up and what's coming at Universe