Summary of the trip to the US

Feb 15th, 2024

In the months of October and November 2023 together with Johannes Schickling and Mirela Prifti we traveled to the United States to meet with interesting folks and to hold a meetup in San Francisco.

First of all I want to thank my travel companions. They made such a trip far more fun and interesting than it would have been without and made it possible to organize the meetup in the best possible way.

Starting with the meetup, it was held in the beautiful office space of Amplify Partners that offered to host us free of charge. We would like to thank them as it would have been much harder to reach the same quality without such an offer.

The meetup was highly participated and filled up with incredibly interesting folks such as Shawn Wang, Theo Browne, Dominik Tornow, David Siegel, Tim Suchanek, Marie Schneegans and many more. The vibe was positive and we had lots of fun eating pizza and drinking sparkling water (and beer).

We had 3 talks:

  • opening the evening was myself (Michael Arnaldi) talking about “The Why” of Effect
  • followed by Johannes Schickling that spoke about his experience of building Overtone with Effect
  • closing with Thomas Ballinger from Convex that talked about how some of their customers are using Effect together with Convex.

We learned a lot from the meetup, personally received valuable feedback on my talk from Theo (that I thank immensely) and most importantly we learned to bring with us recording equipment, the reason why you won’t find high quality recordings.

Apart from the meetup we met with a lot of interesting people that we would like to thank for their time and insights provided.

Key takeaways from meetings were:

  • The Effect learning curve is becoming more approachable, but it is still a bit steep.
  • Observability is something everyone wants but it is hard to get. Effect can help there.
  • The problems that Effect resolves are real and huge in production, but it is hard to see them at first unless you’ve experienced them before.
  • TypeScript is becoming the de-facto preferred language for development of backend systems, not only frontends, Effect fits perfectly in that spot.
  • Integrations (and by consequence Workflows) are a huge pain point where the reliability aspects of Effect can be key.

Following the minutes from the meetings:

  • Maxwell Brown: The one and only! We shared a nice dinner in NJ and discussed the future of Effect together.
  • Kelley Mak: GP at Work-Bench in NY. We had a great chat and Kelley will help us organize an OSS founders dinner in Queens themed around Asian Food next time we’ll visit.
  • Jamie Turner: CEO of Convex. We discussed everything related to building and scaling devtools.
  • Thomas Ballinger: Senior Developer at Convex. We discussed how some of their users are using Effect and what benefits we could gain from a deeper integration
  • David Khourshid: CEO of Stately and Author of XState. We discussed the orthogonal benefits of statecharts and effect systems and how to make the learning curve of such complex systems easier to grasp. We also “stole” from David a lot of insights into the peculiarities of building open-source-first companies.
  • Jarred Sumner: CEO of Oven and Author of Bun. We discussed with Jarred the importance of JavaScript as a backend language and the future of the ecosystem. We learned from Jarred a great deal of insight about making tools that people like.
  • Jake Cooper: CEO of Railway. We discussed every possible topic related to building and scaling cloud products, we gained an immense amount of insights about what kind of services are best to be deployed in Railway (or similar) as opposed to serverless and we found common ground in thinking that workflow-like systems (such as the ones we will be able to build thanks to Effect Cluster) would be perfect for such platforms.
  • Christian Glassiognon: Founder of We learned from Christian the challenges of building database tooling and discussed how Effect could help some of them, we shared with Christian some insights about building in the open source and shared a great sandwich (described as the best and most expensive sandwich to be found in SF).
  • Dominik Tornow: CEO of Resonate and former Principal at Temporal. We discussed every aspect of durable computing, a topic for which we all share a lot of love. We gained some insights about how to build and scale such systems and what the future will look like with durable continuations available in almost every language.
  • Josh Curl: Founder and CTO of We discussed with Josh the challenges of building integrated systems that have to talk to many different sources and discussed how Effect could help solving some of their problems
  • Tanishq Kancharla: Full-Stack Developer. We discussed with Tanishq the challenges of learning Effect and learned a great deal of insight about the importance of choosing proper naming conventions
  • Shawn Wang: The one and only Swyx. We learned from Swyx a lot of insights about AI and Workflows and about the DevRel aspects of making a technology known. We discussed everything related to building companies from scratch and the challenges that we all face as founders.
  • Guillermo Rauch: CEO of Vercel and Author of Next.js. It is hard to describe in a few words the depth of the conversation we had with Guillermo, we expected everything but “It makes total sense” as a reaction when we showed the prototype integration between Effect and RSC through Next.js, we share with Guillermo the same vision of what we would like code to look like in the not-to-far future, namely we deeply agree on blurring the boundaries between frontend and backend and about the importance of observability and testability at scale, almost as a “joke” (but not too much) it was even mentioned that something like Next.js and RSC in the future should be built on top of Effect (not that it is realistic or planned in any way).
  • Cheng Lou: Software Engineer at Midjourney. Cheng is a pioneer of effect systems and language design, we discussed with Cheng every aspect of effect systems including the challenges and potential drawbacks that they bring. We had a glimpse about some of the things that Cheng is working on and they are absolutely mind-blowing. I had the pleasure of witnessing Full Self Drive when Cheng offered to take me back home.
  • Brian Douglas: CEO of Open Sauced and former Director of Developer Advocacy at Github. We discussed with Brian everything about open source and developer advocacy, learned tons of insights on what matters when running a successful open source project.
  • Theo Browne & Mark R. Florkowski: CEO & CTO of We learned a lot from Theo and Mark on what matters when making tools for the mass and how to make them popular. We discussed with them some of the challenges that they currently face with UploadThing (absolutely the best name) and how Effect could help them. Johannes went on to start a hacking session to potentially use Effect in their codebase.
  • Tom Preston-Werner: Founder and Former CEO of Github, Author of Redwood and a pioneer of the open source. We discussed everything related to open-source and open-source first companies, frameworks and the future of development, shared a great lunch and discussed among other things the importance of taking care of the environment.
  • Jason Laster: CEO of, we had a nice “DevTools” dinner with Jason and other devtools founders, we learned from Jason the challenges of building tools for debugging and got a glimpse into what the future of debugging could look like.