JetBrains JavaScript Day 2025

Ant Man is stuck in The Quantum Realm, and the only way to get out is by using (you guessed it) Quantum Algorithms! We’re stuck up here in the non-Quantum Realm, so we have to help Ant Man and his friends with the best tool we have - JavaScript!

JavaScript fatigue is real! In multiple ways...

Are you tired of slow builds, long feedback loops and the endless debate over which tools to use? Then this talk is for you.

We will look into modern JavaScript tooling that not only "just works" but is also fast. From Vite as shared infrastructure of the web, to Rolldown, a Rust-based bundler which will be used by Vite in the future to the lower levels with Oxc - the Oxidation JavaScript compiler.

After this talk you will have a better understanding of the tools and how they can improve your development workflow right after your talk - without choice fatigue.

Modern monorepo tooling must go beyond traditional build orchestration to create a cohesive developer experience. Learn how Nx's powerful terminal UI, deep editor integrations, and AI-agent compatibility work together to transform the way teams work with large-scale JavaScript projects.

We are entering a new era of user interaction. It's being built right before our very eyes and changing rapidly. As crazy as it sounds, soon each one of us will get our own Jarvis capable of performing actually useful tasks for us with a completely different user interaction mechanism than we're used to.

But someone's gotta give Jarvis the tools to perform these tasks, and that's where we come in.

In this talk, Kent will show how this AI assistant user interaction model is shaping out to be, help us catch the vision of what this future could look like, and our role in it.

Signals and fine-grained reactivity have recently become staples in modern JavaScript frameworks. However, 9 years ago, when Ryan Carniato created SolidJS, the blueprint for the modern framework, that was not the case at all. Today more developers use Signals than ever before, but we are only at the beginning of the journey. Join Ryan as he looks to the future of fine-grained reactivity, web development, and explores what lies beyond Signals.

Server-side rendering with micro-frontends presents unique architectural challenges, and in this talk, attendees will dive deep into server-side composition patterns for micro-frontends, exploring Astro.js server islands and Next.js multi-zones. Drawing from real-world experience helping global enterprises migrate to micro-frontends across industries, Luca will share battle-tested patterns that lead to successful implementations, including insights from five years of helping customers. Considering the amount of teams currently implementing micro-frontends and many using Next.js, this session is designed for frontend engineers who want to learn what works and what doesn't when combining SSR with micro-frontend architectures in enterprise environments.

Transparent communication is hard and frankly, we're not always great at it. We know you have questions about WebStorm's performance, pricing decisions, feature priorities, and the bugs that drive you crazy, but we rarely address them with the honesty they deserve. This talk changes that by giving you direct, unfiltered answers and a behind-the-scenes look at how we actually make product decisions, while also addressing the misconceptions and biases that might be keeping you from giving WebStorm a fair shot.

Bun is a fast, modern JavaScript runtime. Powered by JavaScriptCore and written in Zig, it combines performance optimizations with built-in tools like a bundler, test runner, and package manager. This talk explores how Bun achieves its speed and what it unlocks for developers today.

Lots of people contribute to open source projects, like Angular, but very few people are maintainers. So what's that like? Learn about all the ins and outs of how decisions are made for big open source projects. You'll get to merge this knowledge upstream when Jessica shares her experiences.