Cassidy Williams
Cassidy Williams
Cassidy Williams
Hi! I’m Cassidy, and I like to make memes and dreams and software. I’m the Senior Director of Developer Advocacy at GitHub! Outside of that fancy title, I’m a startup advisor and investor, open source-er, and meme-maker on the internet. I enjoy building mechanical keyboards, playing music, hanging out with my family and friends, and teaching in my free time.
Latest Posts
My poor Sony a6100 camera (with a Sigma 30mm lens) died on me this week. It served me well for over 6 years! I replaced it with my husband’s a6400 that he wasn’t using anymore, and because of various adjustments on my desk that I made at...
I found this old article about making wavy lines with CSS, and decided to play around with it! Here’s the final result: See the Pen Wavy diving board by Cassidy (@cassidoo) on CodePen. It’s not the most gorgeous art in the world, but it...
I’ve been asked a couple times just this week how passkeys work, here’s a little rundown! What passkeys are and how they work The “sales pitch” for passkeys is that they’re like a password that you will never know, and can never leak....
I’ve always loved making videos. Not because I love being on camera, but I really enjoy putting together jokes and stories and tutorials (etc) with video as a medium. The moment I had the ability to plug a camera into a computer back in...
When it comes to certain projects, I like “doing things that don’t scale.”, particularly with my newsletter. I noticed that my newsletter open rate was down over the past few months to about 40-45%. Not bad, but not as good as it once...
I stumbled upon the CSS property corner-shape recently and it’s pretty cool. It allows you to specify the shape of an element’s corners and works with border-radius. I threw together this demo to show it in action: See the Pen...
I switch back and forth between Windows and Mac pretty regularly depending on what I’m working on (and sometimes between WSL and PowerShell on the same machine, what a time to be alive), and one thing that I always mess up in PowerShell...
I have been getting a lot of newsletter responses, DMs, and emails in general saying that people have discovered my work not via traditional SEO, but via LLMs and AI tools like ChatGPT, Claude, Perplexity, and even GitHub Copilot. So, I...
I made a game called Code Wave for the recently completed GitHub Game Off 2025! I really enjoy game development, but don’t get to do it often. When I saw that the theme this year for the Game Off was WAVES, I thought that it would be fun...
My mom taught art appreciation when I was growing up, and I love looking at different artists’ works over time and remembering what I was taught as a kid, and seeing things through a different lens as an adult. My latest rabbit hole has...
In case you missed it, I have a little AI Manifesto here on this blog. I do use AI for work, and often shill AI for work, and use it often on side projects. That being said, I really care about using AI as a tool, rather than a...
I gave a short talk today to some students at Haverford College and Bryn Mawr College about AI, a career in tech, networking, and getting jobs in general! My friends Lilly and Johnson from FSH Tech are teaching a J-Term course at these...
Wow. 2025 is done. It’s been… a lot? A lot. It’s been a lot. Similar to my 2024 recap, I’ve got a lot to write before midnight strikes, so let’s get into it. Work things! I’m still working at GitHub! This year my team was a content...
It’s been a hectic, busy month, truly so so busy, but I blogged every day for Blogvent! In case you missed it, my goal was to blog daily in December. I missed it! No you didn’t! Check out alllll the posts here: Automatically mark pull...
It’s Blogvent, day 23, where I blog daily in December! This month I went to the GitHub office in San Francisco and met up with some coworkers and put together some videos for work. While working on other content, we got a lot of b-roll...