Static Analysis for Ruby with Jake Zimmerman

Dynamic languages like Ruby, Python, and JavaScript determine the types of variables at runtime rather than at compile time. This flexibility allows for rapid development and concise code, but it also makes it harder to catch certain classes of bugs before execution. Type checkers for dynamic languages add structure and safety without compromising their expressive power. Sorbet is a static type checker developed by the Stripe team and designed specifically for Ruby. The motivation behind Sorbet stemmed from the growing complexity of production Ruby applications, where developers needed stronger guarantees and more scalable code quality tools than dynamic typing alone could offer. Jake Zimmerman is a software engineer at Stripe and leads development on Sorbet. He joins the podcast with Josh Goldberg to discuss his background, the challenges of typing in Ruby, the motivation behind Sorbet, its architecture, performance optimizations, and more. This episode is hosted by Josh Goldberg, an independent full time open source developer. Josh works on projects in the TypeScript ecosystem, most notably TypeScript ESLint, a powerful static analysis toolset for JavaScript and TypeScript. He is also the author of the O'Reilly Learning TypeScript book, a Microsoft MVP for developer technologies and a cofounder of SquiggleComp, a conference for excellent web developer tooling. Find Josh on Blue Sky, Fostodon, and .com as Joshua k Goldberg. With me today is Jake Zimmerman, developer at Stripe on Sorbet and Ruby Infrastructure. Jake, welcome to Software Engineering Daily. Awesome. Thanks for having me, Josh. We're really excited. You do a lot of really interesting work, and you have a long history of very fascinating blog posts. But before we get into Sorbet and type checking in Ruby, can you tell us how did you get into tech? Oh, sure. It's a long story. It goes back all the way to seventh grade. My school had a elective for computer science and an elective for, like, mechanical engineering. I took both of them, and I liked the software side of computer science more. So, yeah, I've been working on tech stuff basically since middle school and, yeah, then all through college. And so it's kind of been a very long love of mine. And in university, based on your website, you were involved in student groups, and you took quite a few interesting classes. Was there anything that jumped out to you then that's now relevant to your work on survey today? Yeah. I think the thing that's relevant today is how much being a teaching assistant in college feels like helping out with the onboarding program in industry. There's a lot of overlap in terms of just trying to come up with exciting ways to keep people engaged because the people who started your company are similarly kind of, like, checked out in the first week where there's just so much going on, so much to learn, and you kinda wanna give them all the tools that they need for their job, but you recognize that they're not gonna remember …