Runtime Error: Writing JS Libraries in the Age of Fragmentation
Building for the web used to mean fighting browser quirks. Now, it's runtime quirks. Node.js, Deno, Bun, Cloudflare Workers, Edge runtimes, React Native, they all run JavaScript, sort of. Each comes with its own gotchas.
Throw in ESM vs CJS, native TypeScript vs compiled JS, export maps, bundlers, and half-supported compatibility layers, and you’ve got a new kind of chaos.
In this talk, I’ll share the challenges we faced building the OpenAI Agents SDK and how we navigated the messy modern JS landscape.
About Dominik Kundel
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I LOVE CascadiaJS. Incredible conference in a beautiful city with solid lineups, wonderful staff, and just the right amount of silly. Also @crtr0 at karaoke. 💙
— Josh Goldberg 🦋 (@JoshuaKGoldberg) June 22, 2024
Congrats & thanks again for such a wonderful time! https://t.co/3jhkI8O6Su
I 💚 CascadiaJS bc it feels like the cool, cult classic of JS events.
— Michelle Bakels (@MichelleBakels) March 28, 2025
It’s got everything — a dedicated fan base of 10+ years, close family vibes, long held traditions (the best karaoke!), sublime locale, and a flair for the atypical/creative conf sessions.
Def apply + attend! https://t.co/yqrEbh0icL
The reason why @CascadiaJS is one of my favorite conferences is because you can truly feel the passion and care that everyone puts into it. There's a real sense of community, it's amazing 🙌👏💜
— Charlie Gerard (@devdevcharlie) September 2, 2022
Once again, @CascadiaJS did not disappoint—I love that we have a community-focused conference right in the PNW. It's always inspiring to hear about what people are making, stretch my perspective, and meet new friends.
— Mark Palfreeman 🪐 (@markpalfreeman) September 3, 2022
Also Sunriver resort was awesome 🤘#CascadiaJS pic.twitter.com/SKlPeHibHE
Happy 10th Birthday @CascadiaJS, and thanks to @crtr0 and @carrie_k for shepherding this amazing conference! Can't wait for #CascadiaJS 2024! pic.twitter.com/Pu8p0oewer
— Jeremy's got a #NewThing 🇺🇲🇺🇦 (@IAmJerdog) September 2, 2022
On my way out of @CascadiaJS, feeling grateful for the work that @crtr0, his family, the staff and volunteers, sponsors, speakers, and all put into this family reunion.
— Tejas Kumar (@TejasKumar_) September 3, 2022
Some wonderful memories were made, and the combination of nature and lovely people made it so special. pic.twitter.com/F4JC0318pe
Wow, what a week at @CascadiaJS! Our team thoroughly enjoyed connecting with other engineers, learning from various talks, & experiencing beautiful Sunriver, OR. We wanted to thank everyone who helped organize this event; it was spectacular, and we cannot wait to be back in 2024. pic.twitter.com/vCO33rBTFa
— Formidable, Now Nearform (@FormidableLabs) September 6, 2022
I'm absolutely blown away by how much @cartwr and the entire team @CascadiaJS lifts up and highlights the people who contribute to and make this conference so special. This is what a conf that focuses on community looks like! 🌲 #cjs19 pic.twitter.com/Yh0CdOzVyx
— Divya (@shortdiv) November 9, 2019
I absolutely LOVED MCing @CascadiaJS! This was such a well organized conference, huge kudos to the speakers, the organizers, the sponsors, and of course the audience + community for making it great. It was a pleasure!! #cjs20 pic.twitter.com/EhqjhYJEVY
— Cassidy (@cassidoo) September 3, 2020
Attended #CascadiaJS last week! Awesome speakers/workshops and very well done virtual/hybrid experience! Can't recommend it enough for developers no matter where they are in their coding journey! 🖥️🌲#webdevelopment #javascript #CascadiaJS2021 #PNW pic.twitter.com/imknQzJmBZ
— Nathan Pickard (@NathanPickard) November 8, 2021
Had an amazing time at @CascadiaJS. See you next year! pic.twitter.com/eJYIkqHVMf
— Treasure Porth (@treasureporth) November 13, 2019
I was honored to participate in #CascadiaJS again this year. I've been so impressed again with all the creativity and effort the organizers, speakers, and community puts into making it a uniquely fun event. ✨ pic.twitter.com/x0byI4utED
— Nicole Oliver (@nixcodes) November 5, 2021
Huge shoutout to the @CascadiaJS organizers for a truly unique experience that went above and beyond anything I could have imagined. You could really feel their passion for the community and the time, attention, and care they put into every single aspect. THANK YOU!! ❤️🌲 #cjs20 pic.twitter.com/5NH2FVfMA2
— Rachael Thomas (@rachael_codes) September 3, 2020
Yeah, tonight was great. #CascadiaJS pic.twitter.com/4hHgTP46fg
— Jessica West (@jessicaewest) November 5, 2021
Awesome @CascadiaJS afterparty at the @LivingComputers
— Welling Guzmán (@wellingguzman) November 17, 2018
I had so much fun. #CJS18 pic.twitter.com/xUiF2iupz6
I can't thank @crtr0, the @CascadiaJS team, and the conference sponsors enough for the opportunity to attend #cascadiajs! Everyone was so encouraging and welcoming, I'm thrilled to bring back what I learned to @MakeThinkCode & @pnca. pic.twitter.com/5hVyhcmyUL
— meganmckissack (@meganmckissack) November 19, 2018