💡Recent insight: gaslighting @claudeai seems to improve code quality >90% of the time. “You overengineered this, there is a simpler way” “There is a smaller delta that buys us most of the benefits” “There is a more elegant way” “This is not architecturally coherent” …before I even read its code. 😆

Implementing `polygon(round)` was a challenging yet incredibly rewarding process. We received tremendous support from the Blink CSS, Paint, Opera and Skia teams. It’s finally set to debut in Chrome 150! groups.google.com/a/chromium…

Before we claim that LLMs generate bad frontend code, we should establish the frame of reference. Bad compared to what? Many of these discussions compare LLMs against some idealized standard of “perfect” frontend code, forgetting the realities of most human-authored code that came before them. In my experience, LLMs produce *far* better code than the average frontend developer, just not better than the superstar top 1% dev.

Is it just me or did @claudeai get less competent lately? Terrible overengineering, poor abstractions, missing the point entirely, and all of that with terrible latency. A shadow of its former self! It’s starting to remind me of Codex back in Feb (no idea what it's like now). Nothing new installed, no new config. @DmitrySharabin noticed the same thing. Today, he switched back to Opus 4.6, in hopes. I’m holding back to see how his experiment goes before switching myself, but it’s driving me insane.

Thrilled this is now out, keeping quiet has been SO HARD! 🤐 I’ve had the opportunity to contribute to this project as a domain expert consultant over the past few months, and have seen firsthand the level of thoughtfulness and genuine care for developers and the web platform that has gone into it. ❤️ It’s still very early days, but I’m really proud to have played a small part, and excited for what's next. Looking forward to seeing what folks build with it!

The current state of AccentColor/AccentColorText: 4 browsers, 4 different color pairs From left to right: Chrome 148 (stable), Chrome 150 (canary), Safari, Firefox. - No browser uses the accent-color property for it (Sep 2025 spec change) - Chrome: had removed support, re-adding w/ with a hardcoded blue and automatic AccentColorText - Safari: hardcoded blue, always black text (?) If so, yikes. - Firefox: actual OS accent color, automatic AccentColorText Why would all browsers not use the real OS accent color? Fingerprinting concerns. Up to you whether this is a reasonable tradeoff. 🤷🏽‍♀️

🚨 What are some modern web platform (CSS, HTML, JS) features that you wish your AI agent utilized, but doesn't (or gets them wrong)? I’ll go first: - CSS: lh unit, trig functions, nesting - HTML: inert attribute - JS: Object.groupBy(), Regex lookbehind, regex named groups, RegExp.escape()

🤩 Turns out *both* Chrome & Safari quietly implemented calc(length/length) last year and it's reached 80% market share! Testcase: codepen.io/leaverou/pen/ByQy… caniuse: caniuse.com/mdn-css_types_ca… Sadly, @janeori's atan2 hack won't work in Firefox as a fallback dev.to/janeori/css-type-cast…

Our implementation has been merged into Chrome Canary; please enable the `enable-experimental-web-platform-features` flag . Enjoy it! 🔥🔥 codepen.io/yisi/pen/NPRLEQN

I and @imCGQAQ are currently working on implementing the CSS `polygon() round` keyword in Chrome. This is one of my favorite CSS features! Thanks to @LeaVerou for bringing it to CSS. The CodePen link is coming soon.

Thank you all for voting! Thanks to your input we managed to reverse the resolution that forced all mixins to be scoped — sibling and ancestor rules will no longer be silently dropped from mixins. 🎉 Relevant WG resolution: github.com/w3c/csswg-drafts/… My slides: webplatform.design/talks/mix…

This ended up being such a useful lil' utility I just published a package with it so others can enjoy hassle-free #JS symbols by the truckload! npmjs.com/package/get-symbol…

Looks like there's a bug with @X polls right now (e.g. I see 0 votes although I know people who have voted). Hopefully votes are still stored and will eventually be counted! I set up a poll here if you want to make sure your vote is counted: github.com/LeaVerou/blog/dis… Or on Mastodon: front-end.social/@leaverou/1…

🚨 Want mixins in CSS? Help the @csswg by telling us what feels natural to you! Look at the code in the screenshot. What resulting widths would you find least surprising? A: All get 100px B: div gets 100px, div > h2 gets 200px, div p gets 300px C: div gets 100px, div > h2 gets 200px, div p gets no width D: div and div > h2 get 100px, div p gets no width Poll in next tweet! Please answer based on what feels natural to you, not what the current proposal says.

Folks don’t want to hear this, but my guess is, in a year, you won’t look at the code your agent writes at all. Doing so would be both beyond your ability and pointless.

After 16 years of using git, it finally happened: I came across a use case for using git to track changes to the .git directory itself. 🥲 (If you guessed that AI agents had a hand in this …you’d have guessed right)

This is great for consumers, but as a library author where do you put skills that teach @claudeai (and other agents) how to use your library effectively? Have we converged to a standard location yet? Does Claude read .claude or CLAUDE.md from node_modules?

I've had to add a CLAUDE .md rule that cli commands should never be chained, only single commands, 1 at a time.

Claude: I can understand complex architectures in minutes and write highly maintainable code in a fraction of the time it would have taken a human! Also Claude: Um, how do I put this. I know you gave me permission to run a bunch of terminal commands, but I need you to approve this one manually because ampersands are hard.

There are currently two mature @TC39 proposals for the low-level functionality that would make it possible to declare *any* file type as a dependency: 1. Import text (Stage 3 as of last week!): github.com/tc39/proposal-imp… 2. Import bytes (Stage 2.7): github.com/tc39/proposal-imp… Perhaps we should push for these to get implemented *first* instead of ad hoc types for every possible type of dependency (CSS modules, HTML modules, etc), which doesn’t scale. Especially Import bytes, which is the root of them all: Even Import text can be trivially implemented on top of it via `new TextDecoder("utf-8").decode(bytes);`