Schedule

Thanks to Expo Router it's easier than ever to build a beautiful app that runs on iOS, Android, and web. With the addition of AI tooling, it's now easier to build an app than it is to deploy one, but it doesn't have to be. Learn about how we've improved Expo Router and how we're making it easier to ship apps everywhere.

React Compiler was introduced back in 2024 as a way to automatically handle performance optimizations in your apps—but how does it work? In this talk, I’ll walk you through some of React Compiler’s internals. We’ll explore its full process, from parsing to Abstract Syntax Tree (AST) transformation, along with its key technologies, benefits, trade-offs, and a practical example of how it transforms your code to prevent unnecessary re-renders.The good news: you (luckily) don’t need to master its internals to integrate it into your codebase. That said, a solid grasp of its internals will significantly enhance your ability to apply the optimization techniques it unlocks!

In this talk, we will explore how to offload work to large language models and automate away most "busy work" in order to maximize and enhance productivity on a daily basis. We will do so mainly by exploring how LLMs can callfunctions.

Lynx, a new cross-platform stack adopted by the TikTok app that empowers teams to ship truly native UIs to mobile and web from a single codebase using their existing web skills like CSS and React, has recently been open sourced.In this talk, we'll explore what makes Lynx familiar and what sets it apart from other cross-platform technologies; we’ll take a closer look at its dual-threaded design, and how that enables Lynx's instant launches and silky-smooth interactions, plus a sneak peak at what's next for Lynx.

Discover how we tackled the common challenges of a large E2E test suite and made our React codebase easier to refactor.In the past year, we went from zero to 20,000 lines of Playwright tests, pushing its capabilities beyond basic end-to-end testing. This talk will explore the challenges we encountered as we scaled our Playwright setup and how we solved them, thanks to the robust ecosystem and team creativity.The talk covers:- Testing approaches and where common tools fit on the testing pyramid- Challenges scaling E2E test suites: performance, flakiness, ownership, mocking and more- How we solved these challenges to unblock refactoring a large React codebase- Advanced Playwright tips and tricks

Metaframeworks: you're probably using one already and may or may not love the experience - but what if I told you they aren’t rocket science?In this talk, we’re ditching the buzzwords and over-complication to build one from scratch—yes, you heard that right.Armed with Vite, Vinxi, Nitro, a pinch of vanilla JavaScript, and a healthy dose of curiosity, we’ll piece together the routing, rendering, and all the essentials you’ve been letting metaframeworks handle for you.Expect aa crash course in understanding the tech you use every day. By the end, you might just be asking: Should I just roll one myself? Aand no, you shouldn't. But it's sure fun building one and understanding what makes them tick, no?

Choosing the best framework is tough, isn't it? We've got Next.js, Remix, and a bunch of others thrown into the mix. So, let's keep it real in this talk—I'll be comparing three of the big contenders: Next.js, Remix, and one surprise package.We'll be looking at some key stuff like Data fetching, Routing, SEO, Performance, Server-side Rendering, and more. Think of it like a friendly showdown where these frameworks go head-to-head in a fair and square matchup.We'll dish out points and see who comes out on top, highlighting which framework rocks for different uses and helping you out with your next project.

Module Federation lets you organize code into federated modules, dynamically loaded at runtime within a host application—a core mechanism behind Super Apps. On the web, this is typically handled with Webpack.Now, with Re.Pack as a Metro alternative, React Native supports it too. This allows existing native Super Apps to transition to React Native and enables truly cross-platform modules, letting developers use React and JavaScript without concern for where modules run.In this talk, we’ll explore these possibilities, best practices and real-world examples to help you build efficient, cross-platform Super Apps.

Website performance significantly impacts user experience, often leading to frustration and anger when pages are slow or unresponsive. Beyond psychological effects, poor performance can increase usage costs and modern websites require a nuanced approach to capture continuous user interactions.This session explores behaviors like rage clicks and cursor thrashing, emphasizing metrics that reflect user emotions and overall satisfaction. We'll discuss the complexities of performance measurement, highlighting the need to look beyond single metrics. Ideal for those interested in understanding the business impact of site performance and the biases affecting user perceptions.

At JavaScript Mastery, we've built a scalable learning platform to serve millions of developers worldwide—and the process came with its own unique challenges and takeaways. Traditional learning platforms suffer from rigid structures, low retention, and scalability bottlenecks, so we set out to create a flexible, high-performance system that could grow with our audience.In this talk, I'll break down how we engineered a dynamic MDX-based content system with React, enabling seamless integration of videos, interactive coding, and AI-powered quizzes.I’ll dive into:React Server Components & streaming rendering for a 40% performance boostNext.js-driven SEO strategies that tripled organic trafficData-driven engagement techniques that significantly improved retentionScaling lessons from serving a global developer audienceThis is a real-world case study of the engineering decisions, challenges, and optimizations that took our platform from an idea to a widely adopted learning ecosystem. Whether you're scaling an LMS or any content-driven application, these insights will help you build, optimize, and grow your own platforms effectively."

Can we apply the lessons of CSS to JavaScript?While working on StyleX we use compilation and the technique Atomic CSS to create a more efficient system. Having small atomic CSS rules maximizes re-usability and dramatically reduces the size of the CSS at scale. A powerful compiler, makes the process automatic and frees from having to think custom DSLs. Can we do the same for JavaScript?

Use React principles beyond React projects! Come to this talk to learn how to apply componentization, declarative programming, and reusability to general front-end JavaScript tasks. Elevate your skills and create scalable, maintainable codebases irrespective of the framework or library you choose.