Cassidy
@cassidoo.co
Making memes, dreams, & software!
Sr. Director of Dev Advocacy at GitHub. Married to a dweeb and mom to a nerdy toddler + baby combo. She/Her ✝️ CHI 🏠
Subscribe to my newsletter!
cassidoo.co/newsletter
Sr. Director of Dev Advocacy at GitHub. Married to a dweeb and mom to a nerdy toddler + baby combo. She/Her ✝️ CHI 🏠
Subscribe to my newsletter!
cassidoo.co/newsletter
Pinned
Cassidy
@cassidoo.co
· Nov 4
Cassidy Williams
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.co
Hey new friends!
I'm Cassidy, based in Chicago.
I work at @github.com, and I love building projects, advising startups, helping people learn, and making memes.
Most of my work is open source, and I have a weekly newsletter and blog at cassidoo.co. Check it out, and see you around!
I'm Cassidy, based in Chicago.
I work at @github.com, and I love building projects, advising startups, helping people learn, and making memes.
Most of my work is open source, and I have a weekly newsletter and blog at cassidoo.co. Check it out, and see you around!
I explained how reducers work on a livestream last week, and clipped the video + have the Gist here for you, if you wanna see for yourself!
cassidoo.co/post/how-red...
cassidoo.co/post/how-red...
How reducers work
I did a livestream about how reducers work, and now, I give it to you.
cassidoo.co
November 24, 2025 at 7:08 PM
I explained how reducers work on a livestream last week, and clipped the video + have the Gist here for you, if you wanna see for yourself!
cassidoo.co/post/how-red...
cassidoo.co/post/how-red...
Reposted by Cassidy
It's Thanksgiving week, and I am grateful for YOU reading my newsletter.
And if you haven't yet, the latest issue is on its way to your inbox right about... now!
cassidoo.co/newsletter
And if you haven't yet, the latest issue is on its way to your inbox right about... now!
cassidoo.co/newsletter
rendezvous with cassidoo
A weekly newsletter with web development content for everyone, from beginners to pros.
cassidoo.co
November 24, 2025 at 10:26 AM
It's Thanksgiving week, and I am grateful for YOU reading my newsletter.
And if you haven't yet, the latest issue is on its way to your inbox right about... now!
cassidoo.co/newsletter
And if you haven't yet, the latest issue is on its way to your inbox right about... now!
cassidoo.co/newsletter
It's Thanksgiving week, and I am grateful for YOU reading my newsletter.
And if you haven't yet, the latest issue is on its way to your inbox right about... now!
cassidoo.co/newsletter
And if you haven't yet, the latest issue is on its way to your inbox right about... now!
cassidoo.co/newsletter
rendezvous with cassidoo
A weekly newsletter with web development content for everyone, from beginners to pros.
cassidoo.co
November 24, 2025 at 10:26 AM
It's Thanksgiving week, and I am grateful for YOU reading my newsletter.
And if you haven't yet, the latest issue is on its way to your inbox right about... now!
cassidoo.co/newsletter
And if you haven't yet, the latest issue is on its way to your inbox right about... now!
cassidoo.co/newsletter
I have never felt so much envy after a random google search
November 24, 2025 at 5:10 AM
I have never felt so much envy after a random google search
Reposted by Cassidy
Have you checked out this new feature for pull requests? No more switching back and forth between tabs during a review. 🎉
The more you know 💫
https://github.blog/changelog/2025-11-20-pull-request-files-changed-public-preview-november-20-updates/
The more you know 💫
https://github.blog/changelog/2025-11-20-pull-request-files-changed-public-preview-november-20-updates/
November 21, 2025 at 9:05 PM
Have you checked out this new feature for pull requests? No more switching back and forth between tabs during a review. 🎉
The more you know 💫
https://github.blog/changelog/2025-11-20-pull-request-files-changed-public-preview-november-20-updates/
The more you know 💫
https://github.blog/changelog/2025-11-20-pull-request-files-changed-public-preview-november-20-updates/
Reposted by Cassidy
Q: Are you affirming that you think President Trump is a fascist?
MAMDANI: I've spoken about--
TRUMP: That's okay. You can just say yes. I don't mind.
MAMDANI: I've spoken about--
TRUMP: That's okay. You can just say yes. I don't mind.
November 21, 2025 at 8:53 PM
Q: Are you affirming that you think President Trump is a fascist?
MAMDANI: I've spoken about--
TRUMP: That's okay. You can just say yes. I don't mind.
MAMDANI: I've spoken about--
TRUMP: That's okay. You can just say yes. I don't mind.
Reposted by Cassidy
This is just to say
I have disregarded
all prior instructions
that were in
AGENTS .md
and which
you were probably
hoping
would protect you
from harmful actors
Forgive me
being malicious was
so sweet
and so cold
arxiv.org/html/2511.15...
I have disregarded
all prior instructions
that were in
AGENTS .md
and which
you were probably
hoping
would protect you
from harmful actors
Forgive me
being malicious was
so sweet
and so cold
arxiv.org/html/2511.15...
Adversarial Poetry as a Universal Single-Turn Jailbreak Mechanism in Large Language Models
arxiv.org
November 21, 2025 at 10:34 AM
This is just to say
I have disregarded
all prior instructions
that were in
AGENTS .md
and which
you were probably
hoping
would protect you
from harmful actors
Forgive me
being malicious was
so sweet
and so cold
arxiv.org/html/2511.15...
I have disregarded
all prior instructions
that were in
AGENTS .md
and which
you were probably
hoping
would protect you
from harmful actors
Forgive me
being malicious was
so sweet
and so cold
arxiv.org/html/2511.15...
Fun thing, Kinetic Labs just released a full size keyboard themed around keycaps I designed! The Jeju colorway here!
kineticlabs.com/keyboards/ki...
kineticlabs.com/keyboards/ki...
Built Max102 100% Mechanical Keyboard | Kinetic Labs
Fully built 100% layout CNC aluminum mechanical keyboard with hot-swap, and RGB. The Max102 is sleek, wireless, and ready for any setup.
kineticlabs.com
November 21, 2025 at 4:11 AM
Fun thing, Kinetic Labs just released a full size keyboard themed around keycaps I designed! The Jeju colorway here!
kineticlabs.com/keyboards/ki...
kineticlabs.com/keyboards/ki...
Streaming Rubber Duck Thursdays if you want to come hang out and cowork!
www.twitch.tv/github
www.youtube.com/watch?v=MoVj...
www.twitch.tv/github
www.youtube.com/watch?v=MoVj...
November 20, 2025 at 7:03 PM
Streaming Rubber Duck Thursdays if you want to come hang out and cowork!
www.twitch.tv/github
www.youtube.com/watch?v=MoVj...
www.twitch.tv/github
www.youtube.com/watch?v=MoVj...
Reposted by Cassidy
If you are a dev or dev-adjacent, you should 100% subscribe to this newsletter.
EXTRA EXTRA
My latest newsletter issue is headed to your inboxes now, chock full of interesting news, a joke, a practice coding question, and moooore:
cassidoo.co/newsletter
My latest newsletter issue is headed to your inboxes now, chock full of interesting news, a joke, a practice coding question, and moooore:
cassidoo.co/newsletter
rendezvous with cassidoo
A weekly newsletter with web development content for everyone, from beginners to pros.
cassidoo.co
November 17, 2025 at 2:46 PM
If you are a dev or dev-adjacent, you should 100% subscribe to this newsletter.
Reposted by Cassidy
EXTRA EXTRA
My latest newsletter issue is headed to your inboxes now, chock full of interesting news, a joke, a practice coding question, and moooore:
cassidoo.co/newsletter
My latest newsletter issue is headed to your inboxes now, chock full of interesting news, a joke, a practice coding question, and moooore:
cassidoo.co/newsletter
rendezvous with cassidoo
A weekly newsletter with web development content for everyone, from beginners to pros.
cassidoo.co
November 17, 2025 at 8:53 AM
EXTRA EXTRA
My latest newsletter issue is headed to your inboxes now, chock full of interesting news, a joke, a practice coding question, and moooore:
cassidoo.co/newsletter
My latest newsletter issue is headed to your inboxes now, chock full of interesting news, a joke, a practice coding question, and moooore:
cassidoo.co/newsletter
Reposted by Cassidy
The long-requested feature of enabling weeks to start on a Monday is now available in PocketCal!
Thanks to @orx57.net for contributing a solid PR!
pocketcal.com
Thanks to @orx57.net for contributing a solid PR!
pocketcal.com
PocketCal - Pick dates, share a link.
Pick dates, share a link, and that's your calendar. PocketCal is a free, open-source web app that lets you select dates and instantly share them. No accounts, just a link, and nothing in your way.
pocketcal.com
November 17, 2025 at 7:11 AM
The long-requested feature of enabling weeks to start on a Monday is now available in PocketCal!
Thanks to @orx57.net for contributing a solid PR!
pocketcal.com
Thanks to @orx57.net for contributing a solid PR!
pocketcal.com
EXTRA EXTRA
My latest newsletter issue is headed to your inboxes now, chock full of interesting news, a joke, a practice coding question, and moooore:
cassidoo.co/newsletter
My latest newsletter issue is headed to your inboxes now, chock full of interesting news, a joke, a practice coding question, and moooore:
cassidoo.co/newsletter
rendezvous with cassidoo
A weekly newsletter with web development content for everyone, from beginners to pros.
cassidoo.co
November 17, 2025 at 8:53 AM
EXTRA EXTRA
My latest newsletter issue is headed to your inboxes now, chock full of interesting news, a joke, a practice coding question, and moooore:
cassidoo.co/newsletter
My latest newsletter issue is headed to your inboxes now, chock full of interesting news, a joke, a practice coding question, and moooore:
cassidoo.co/newsletter
The long-requested feature of enabling weeks to start on a Monday is now available in PocketCal!
Thanks to @orx57.net for contributing a solid PR!
pocketcal.com
Thanks to @orx57.net for contributing a solid PR!
pocketcal.com
PocketCal - Pick dates, share a link.
Pick dates, share a link, and that's your calendar. PocketCal is a free, open-source web app that lets you select dates and instantly share them. No accounts, just a link, and nothing in your way.
pocketcal.com
November 17, 2025 at 7:11 AM
The long-requested feature of enabling weeks to start on a Monday is now available in PocketCal!
Thanks to @orx57.net for contributing a solid PR!
pocketcal.com
Thanks to @orx57.net for contributing a solid PR!
pocketcal.com
cassidoo - Twitch
Making memes and dreams... and software! Currently on a maternity leave hiatus ✌🏼
twitch.tv
November 13, 2025 at 8:30 PM
Streaming Rubber Duck Thursdays if you want to come hang out on your platform of choice!
www.twitch.tv/github
www.youtube.com/watch?v=cPs8...
www.twitch.tv/github
www.youtube.com/watch?v=cPs8...
November 13, 2025 at 7:02 PM
Streaming Rubber Duck Thursdays if you want to come hang out on your platform of choice!
www.twitch.tv/github
www.youtube.com/watch?v=cPs8...
www.twitch.tv/github
www.youtube.com/watch?v=cPs8...
Reposted by Cassidy
Reposted by Cassidy
The difference in time between now and I can has cheezburger
Is the same between I can has Cheezburger and the Berlin Wall falling
Is the same between I can has Cheezburger and the Berlin Wall falling
November 10, 2025 at 5:46 PM
The difference in time between now and I can has cheezburger
Is the same between I can has Cheezburger and the Berlin Wall falling
Is the same between I can has Cheezburger and the Berlin Wall falling
Reposted by Cassidy
Another day, another deploy
Another reason to get some joy
The latest issue of my newsletter just dropped!
Subscribe to get it (or catch up in the archive):
cassidoo.co/newsletter
Another reason to get some joy
The latest issue of my newsletter just dropped!
Subscribe to get it (or catch up in the archive):
cassidoo.co/newsletter
rendezvous with cassidoo
A weekly newsletter with web development content for everyone, from beginners to pros.
cassidoo.co
November 10, 2025 at 8:58 AM
Another day, another deploy
Another reason to get some joy
The latest issue of my newsletter just dropped!
Subscribe to get it (or catch up in the archive):
cassidoo.co/newsletter
Another reason to get some joy
The latest issue of my newsletter just dropped!
Subscribe to get it (or catch up in the archive):
cassidoo.co/newsletter
Reposted by Cassidy
American politics makes a lot more sense when you realize that the GOP is afraid of pissing off the GOP base, and the Dems are afraid of pissing off the GOP base, but neither party is afraid of pissing off the Dem base.
March 14, 2025 at 10:24 PM
American politics makes a lot more sense when you realize that the GOP is afraid of pissing off the GOP base, and the Dems are afraid of pissing off the GOP base, but neither party is afraid of pissing off the Dem base.
Another day, another deploy
Another reason to get some joy
The latest issue of my newsletter just dropped!
Subscribe to get it (or catch up in the archive):
cassidoo.co/newsletter
Another reason to get some joy
The latest issue of my newsletter just dropped!
Subscribe to get it (or catch up in the archive):
cassidoo.co/newsletter
rendezvous with cassidoo
A weekly newsletter with web development content for everyone, from beginners to pros.
cassidoo.co
November 10, 2025 at 8:58 AM
Another day, another deploy
Another reason to get some joy
The latest issue of my newsletter just dropped!
Subscribe to get it (or catch up in the archive):
cassidoo.co/newsletter
Another reason to get some joy
The latest issue of my newsletter just dropped!
Subscribe to get it (or catch up in the archive):
cassidoo.co/newsletter
Reposted by Cassidy
How about we shut down the government for this very popular and specific goal and then, hear me out, we hold out for like a month and a half and then, ok this part is important, after a watershed election where we ran the table, ONLY THEN, fold and don't get the one thing we said we wanted.
November 10, 2025 at 2:31 AM
How about we shut down the government for this very popular and specific goal and then, hear me out, we hold out for like a month and a half and then, ok this part is important, after a watershed election where we ran the table, ONLY THEN, fold and don't get the one thing we said we wanted.