Web Performance Special — with Harry Roberts & Leaning Technologies

Join us this May for a special Leeds JS event focused entirely on web performance — one of the most critical (and often overlooked) aspects of modern web development.
We’re thrilled to welcome Harry Roberts (csswizardry.com), an award-winning web performance consultant and international speaker. Harry has worked with organisations like Google, the BBC, and the Financial Times to diagnose and fix real-world performance issues, helping teams build faster, more efficient websites.

Expect deep, practical insights into:

• Diagnosing real-world performance bottlenecks
• Building faster, more resilient frontends
• Making performance a core part of your engineering culture

We’ll also be joined by a Developer Relations expert from Leaning Technologies, bringing a unique perspective on high-performance web apps, WebAssembly, and pushing the limits of what’s possible in the browser.

⚡ Whether you’re a frontend engineer, full-stack dev, or just performance-curious, this session will give you actionable techniques you can apply immediately.

Agenda (approx):

• Welcome & intros
• Talk: Ana Gabriela Reyna Flores Leaning Technologies DevRel
• Talk: Harry Roberts — Build for the Web, Build on the Web, Build With the Web
• Q&A + community discussion
• Networking & drinks 🍻

Build for the Web, Build on the Web, Build With the Web

Every layer of abstraction made in the browser moves you further from the platform, ties you further into framework lock-in, and moves you further away from fast.
By using progressive enhancement, you can opt into browser-native features that are usually faster, more accessible, more secure, and—perhaps most importantly to the business—maintained by someone else.

The beauty of opting into web platform features as they become available is that your site becomes contextual. The same codebase adapts into its environment, playing to its strengths, rather than trying to build and ship your own environment from the ground up. Meet your users where they are.