The Path to Performance // Speaker Deck

The Great CSS Expansion | Butler’s Log

Web development follows a familiar cycle. First we glue together a solution with whatever we have — JavaScript, image hacks, Flash, anything. Then the platform matures, and CSS or HTML eventually makes that same workaround native. Rounded corners, custom fonts, smooth scrolling, sticky positioning: all of these started as JavaScript-heavy hacks before CSS turned them into a single declaration.

We are in another one of those transition moments. A new wave of long-requested CSS features is finally landing, and many of them are explicitly designed to replace patterns that used to require JavaScript. Not as approximations — as first-class platform primitives that handle the edge cases, run in the right thread, and need zero dependencies.

NoLoJS: Reducing the JS Workload with HTML and CSS - Web Performance Calendar

You might not need (much) JavaScript for these common interface patterns.

While we all love the power and flexibility JS provides, we should also respect it, and our users, by limiting its use to only what it needs to do.

Yes! Client-side JavaScript should do what only client-side JavaScript can do.

Write Code That Runs in the Browser, or Write Code the Browser Runs - Jim Nielsen’s Blog

So instead of asking yourself, “How can I write code that does what I want?” Consider asking yourself, “Can I write code that ties together things the browser already does to accomplish what I want (or close enough to it)?”

I’m more proud of these 128 kilobytes than anything I’ve built since | by Mike Hall | Jul, 2025 | Medium

I don’t normally link to articles on Medium—I respect you too much—and I do wish this were written on Mike Hall’s own site, but this is just too good not to share.

And don’t dismiss this as a nostalgiac case study from the past:

At no point did the constraints make the product feel compromised. Users on modern devices got a smooth experience and instant feedback, while those on older devices got fast, reliable functionality. Users on feature phones got the same core experience without the bells and whistles.

The constraints forced us to solve problems in ways we wouldn’t have considered otherwise. Without those constraints, we could have just thrown bytes at the problem, but with them every feature had to justify itself. Core functionality had to work everywhere, and without JavaScript crutches proper markup became essential.

This experience changed how I approach design problems. Constraints aren’t a straitjacket, keeping us from doing our best work; they are the foundation that makes innovation possible. When you have to work within severe limitations, you find elegant solutions that scale beyond those limitations.

CSS { In Real Life } | Web Sustainability and the Ethical Dilemma

But is it always the case that faster websites are greener websites? We reluctantly have to consider another facet: if making a website for a car manufacturer faster leads to an increase in the number of cars sold, can we really say that our website is greener?

This is very timely for me, given that Clearleft is currently engaged on a project that’s making me decidedly queasy for this exact reason—the success metrics of the project would be net negative for the world.