Cassidy Williams cassidoo

Diagnose Slow `npm run rayfin:dev` on Windows

You are diagnosing why npm run rayfin:dev (which runs rayfin dev) is extremely slow on this Windows machine. On another machine, the following two fixes brought startup from ~150s down to ~4s:

Windows Defender path exclusions — Defender real-time scanning of thousands of .js files in node_modules causes 100+ second delays on cold starts
Rayfin telemetry opt-out — RAYFIN_TELEMETRY_OPTOUT=1 as a persistent user env var, which prevents loading ~12,000 OpenTelemetry dependency files

Step 1: Run this diagnostic script

Run the following in PowerShell and share the full output:

[System.Environment]::SetEnvironmentVariable("RAYFIN_TELEMETRY_OPTOUT", "1", "User")

Run in an elevated (Admin) PowerShell

Add-MpPreference -ExclusionPath "C:\nvm4w\nodejs\node_modules" Add-MpPreference -ExclusionPath "$env:LOCALAPPDATA\npm-cache" Add-MpPreference -ExclusionPath "$env:USERPROFILE.copilot\repos"

Diagnosing Slow Node.js / npm CLI Startup on Windows

BYOK Controls Cheat Sheet

General Controls

Toggle status bar: Ctrl+SPACE

Cycle backlight brightness: Ctrl+L

Create new file in current project: Ctrl+N

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Test document?

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This is a footnote[^1]. Check it out below.

Look at this image:

Patrick Knight

Who are you and what do you do at GitHub?

Patrick Knight, Staff Product Manager for Repository Governance. I focus on rulesets and customer properties to let you keep you code safe at scale. 2. What did you build? One sentence + a screen recording (Loom link is fine).

A Chrome extension that turns our extensive emoji collection (57k+) into mosaics.

[video]

How Hubbers AI: Ashley Willis

Who are you and what do you do at GitHub? I'm Ashley, Senior Director of Developer Relations at GitHub. I lead a team focused on developer community, content strategy, and helping developers get the most out of GitHub's tools

What did you build? I built Pocket Monster; an AI childcare assistant that helps my older daughter Kylie take care of my 5-year-old Marlowe while my partner and I are traveling in Japan. It's powered by Claude via GitHub's Copilot SDK and has all the specific care instructions, routines, and house quirks that would normally require dozens of text messages back and forth.

How long did v1 take to make? About five hours to get to a functional prototype that actually worked. Then I spent three more days tweaking it obsessively - honestly past the point of usefulness - because I couldn't leave it alone. Classic builder problem.

CLI Crash Course

Hey! This is a quick little "crash course" on how to use your terminal on your computer.

First of all, what is the Terminal?

It's not a hardcore hacker setup like you see in the movies (although you can make it look like one). The terminal is where you talk to your computer using text instead of clicking. It's like having a conversation with your operating system.

Now, to open the terminal, it might look different depending on your computer. On a Mac, you want to open an application called Terminal. On Windows, you have a few options, either Command Prompt, PowerShell, or Windows Terminal. All of these apps come built in with your computer! You can install other ones, but we'll stick with the basics for now.

Memory... all alone in the moonlight...

GitHub Copilot has Memory now, y'all.

We know it can be annoying to have to start from scratch with every session with an AI tool.

Cross-agent memory allows agents to remember and learn from working with you, without relying on explicit user instructions. Each interaction teaches Copilot more about your codebase and conventions, making it better and better over time. Kind of like a cast iron skillet.

Anyway.

	; All Prompt Hotkeys Combined - AutoHotkey v2
	; Run this single file to register all hotkeys
	#Requires AutoHotkey v2.0

	; Ctrl+1 - Go-Live Issues
	^1:: {
	A_Clipboard := "We are going to release this application. List the top 5 GitHub issues we need to address before go-live. Display them in a table with relevant emoji."
	Send "^v"
	}