Cassidy Williams
Cassidy Williams — Senior Director of Developer Advocacy at GitHub
I'm Cassidy Williams, a software engineer, mom, and overall nerd in Chicago. I write about tech, projects, and whatever else I'm thinking about!
cassidoo.coThere's no joy in it. There's no 'YAY I am a GENIUS because I FIGURED IT OUT' feeling. It's just there. It's boring.
Cassidy's blog refuses to stay in a lane. A post about CSS sits next to an essay on Mary Cassatt's paintings. A technical guide is followed by Chicago restaurant recommendations. Posts are short, funny, and unpolished in the best way — she writes like early blogging felt, before personal sites became personal brands. Her annual Blogvent challenge (a post every day in December) is a burst of creative energy worth following along with.
Written by Cassidy Williams since 2009.
Occasional
Publishes a few times per month
14
Independent Blog
English
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Making art with CSS gradients and corner-shape and skew, oh my
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 was interesting combining the wavy gradients with CSS skew and corner-shape for some diagonal lines. I admit I didn’t do this in the most efficient way, but it was fun! I recorded a video of myself going from sketch to Pen, check it out: There was defi...
How passkeys work
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. They’re fully attached to your device of choice (phone, computer, Yubikey, etc). When you’re about to log in to a website with a passkey for the first time, your device makes two keys: a public key for the website that’s safe to share, and a private key that never...
I am making videos again!
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 the early 2000s, I was making videos. But, I’ve not really been consistent about it. I didn’t make many videos regularly in high school and college (outside of some lip sync videos I’ll let you find on your own, heh). The most consistent I’ve been was when I got...
Improving my newsletter's open rate the hard(er) way
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 was. A friend of mine suggested I ask people to respond to the email on occasion to help improve its reputation with Gmail/spam filters. When I did that this past month, my inbox was flooded with responses. I lost count of them if I’m being honest, but there were h...
Making interesting borders with CSS corner-shape
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 corner-shape beveled and rounded navbar by Cassidy (@cassidoo) on CodePen. I remember in the olden days (as in like… 10 years ago, as evidenced by this old Pen of mine), making beveled corners involved a bunch of pseudo-elements and triangles to fake a b...
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