Developer Summit ’25 Day 1 Session 3

Recursion often feels complex to engineers, but once it clicks, it opens up an entirely new way of solving problems. This talk will start with a brief explanation of recursion including how it works under the hood in JavaScript and how to avoid stack overflow issues. From there, we will go through real-world examples by comparing iterative and recursive approaches and demonstrate how recursion can help cleaner and more readable code. We will also see examples where recursion is the more suitable or even necessary approach.

Text inputs, checkboxes, radio buttons, sliders… Form controls have been part of the web since the beginning, but styling them can still feel like a battle. If you’ve spent time struggling to figure out countless lines of CSS to make them look right, or rebuilt native elements from scratch because they weren’t customizable enough, you’re not alone. In this session, we’ll explore why HTML form controls have been so hard to style — and introduce upcoming improvements that will make them easier to customize, using only the power of CSS. You’ll also get a peek at how form controls have evolved, and how the new enhancements fit into the broader web ecosystem. If you’ve ever struggled with form controls, this talk will give you practical insight and a glimpse of what’s next.

Scrolling has come a long way since the concept originated in ancient Egypt. In this talk, we’ll blast through the evolution of scrollytelling — from JavaScript hacks to modern, declarative CSS magic. You’ll learn how scroll-timeline, view-timeline, and scroll-state queries unlock rich, interactive storytelling with minimal CSS and no scripting.