Jeremy Keith
adactio.com.web.brid.gy
Jeremy Keith
@adactio.com.web.brid.gy
Making websites. Writing books. Hosting a podcast. Speaking at events. Living in Brighton. Working at Clearleft. Playing music. Taking photos. Answering email.
Installing web apps
Safari, Chrome, and Edge all allow you to install websites as though they’re apps. On mobile Safari, this is done with the “Add to home screen” option that’s buried deep in the “share” menu, making it all but useless. On the desktop, this is “Add to dock” in Safari, or “Install” in Chrome or Edge. Firefox doesn’t offer this functionality, which as a shame. Firefox is my browser of choice but they decided a while back to completely abandon progressive web apps (though they might reverse that decision soon). Anyway, being able to install websites as apps is fantastic! I’ve got a number of these “apps” in my dock: Mastodon, Bluesky, Instagram, The Session, Google Calendar, Google Meet. They all behave just like native apps. I can’t even tell which browser I used to initially install them. If you’d like to prompt users to install your website as an app, there’s not much you can do other than show them how to do it. But that might be about to change… I’ve been eagerly watching the proposal for a Web Install API. This would allow authors to put a button on a page that, when clicked, would trigger the installation process (the user would still need to confirm this, of course). Right now it’s a JavaScript API called `navigator.install`, but there’s talk of having a declarative version too. Personally, I think this would be an ideal job for an invoker command. Making a whole new `install` element seems ludicrously over-engineered to me when `button invoketarget="share"` is right there. Microsoft recently announced that they’d be testing the JavaScript API in an origin trial. I immediately signed up The Session for the trial. Then I updated the site to output the appropriate HTTP header. You still need to mess around in the browser configs to test this locally. Go to `edge://flags` or `chrome://flags/` and search for ‘Web App Installation API’, enable it and restart. I’m now using this API on the homepage of The Session. Unsurprisingly, I’ve wrapped up the functionality into an HTML web component that I call `button-install`. Here’s the code. You use it like this: <button-install> <button>Install the app</button> </button-install> Use whatever text you like inside the button. I wasn’t sure whether to keep the `button` element in the regular DOM or generate it in the Shadow DOM of the custom element. Seeing as the button requires JavaScript to do anything, the Shadow DOM option would make sense. As Tess put it, Shadow DOM is for hiding your shame—the bits of your interface that depend on JavaScript. In the end I decided to stick with a regular `button` element within the custom element, but I take steps to remove it when it’s not necessary. There’s a potential issue in having an element that could self-destruct if the browser doesn’t cut the mustard. There might be a flash of seeing the button before it gets removed. That could even cause a nasty layout shift. So far I haven’t seen this problem myself but I should probably use something like Scott’s CSS in reverse: fade _in_ the button with a little delay (during which time the button might end up getting removed anyway). My `connectedCallback` method starts by finding the button nested in the custom element: class ButtonInstall extends HTMLElement { connectedCallback () { this.button = this.querySelector('button'); … } customElements.define('button-install', ButtonInstall); If the `navigator.install` method doesn’t exist, remove the button. if (!navigator.install) { this.button.remove(); return; } If the current `display-mode` is `standalone`, then the site has already been installed, so remove the button. if (window.matchMedia('(display-mode: standalone)').matches) { this.button.remove(); return; } As an extra measure, I could also use the `display-mode` media query in CSS to hide the button: @media (display-mode: standalone) { button-install button { display: none; } } If the button has survived these tests, I can wire it up to the `navigator.install` method: this.button.addEventListener('click', async (ev) => { await navigator.install(); }); That’s all I’m doing for now. I’m not doing any `try`/`catch` stuff to handle all the permutations of what might happen next. I just hand it over to the browser from there. Feel free to use this code if you want. Adjust the code as needed. If your manifest file says `display: fullscreen` you’ll need to change the test in the JavaScript accordingly. Oh, and make sure your site already has a manifest file that has an `id` field in it. That’s required for `navigator.install` to work.
adactio.com
November 29, 2025 at 12:23 PM
Belfast TradFest back in July.
November 28, 2025 at 11:37 AM
Today was my last working day for 2025. I’m off until January. Christmas starts now!
November 27, 2025 at 5:29 PM
Wednesday session
November 27, 2025 at 12:15 AM
Why use React?
This isn’t a rhetorical question. I genuinely want to know why developers choose to build websites using React. There are many possible reasons. Alas, none of them relate directly to user experience, other than a trickle-down justification: happy productive developers will make better websites. Citation needed. It’s also worth mentioning that some people don’t _choose_ to use React, but its use is mandated by their workplace (like some other more recent technologies I could mention). By my definition, this makes React enterprise software in this situation. My definition of enterprise software is any software that you use but that you yourself didn’t choose. ### Inertia By far the most common reason for choosing React today is inertia. If it’s what you’re comfortable with, you’d need a really compelling reason _not_ to use it. That’s generally the reason behind usage mandates too. If we “standardise” on React, then it’ll make hiring more straightforward (though the reality isn’t quite so simple, as the React ecosystem has mutated and bifurcated over time). And you know what? Inertia is a perfectly valid reason to choose a technology. If time is of the essence, and you know it’s going to take you time to learn a new technology, it makes sense to stick with what you know, even if it’s out of date. This isn’t just true of React, it’s true of any tech stack. This would all be absolutely fine if React weren’t a framework that gets executed in browsers. Any client-side framework is a tax on the end user. They have to download, parse, and execute the framework in order for you to benefit. But maybe React doesn’t need to run in the browser at all. That’s the promise of server-side rendering. ### The front end There used to be a fairly clear distinction between front-end development and back-end development. The front end consisted of HTML, CSS, and client-side JavaScript. The back end was anything you wanted as long as it could spit out those bits of the front end: PHP, Ruby, Python, or even just a plain web server with static files. Then it became possible to write JavaScript on the back end. Great! Now you didn’t need to context-switch when you were scripting for the client or the server. But this blessing also turned out to be a bit of a curse. When you’re writing code for the back end, some things matter more than others. File size, for example, isn’t really a concern. Your code can get really long and it probably won’t slow down the execution. And if it does, you can always buy your way out of the problem by getting a more powerful server. On the front end, your code should have different priorities. File size matters, especially with JavaScript. The code won’t be executed on your server. It’s executed on all sorts of devices on all sorts of networks running all sorts of browsers. If things get slow, you can’t buy your way out of the problem because you can’t buy every single one of your users a new device and a new network plan. Now that JavaScript can run on the server as well as the client, it’s tempting to just treat the code the same. It’s the same language after all. But the context really matters. Some JavaScript that’s perfectly fine to run on the server can be a resource hog on the client. And this is where it gets interesting with React. Because most of the things people like about React still apply on the back end. ### React developers When React first appeared, it was touted as front-end tool. State management and a near-magical virtual DOM were the main selling points. Over time, that’s changed. The claimed speed benefits of the virtual DOM turned out to be just plain false. That just left state management. But by that time, the selling points had changed. The component-based architecture turned out to be really popular. Developers liked JSX. A lot. Once you got used to it, it was a neat way to encapsulate little bits of functionality into building blocks that can be combined in all sorts of ways. For the longest time, I didn’t realise this had happened. I was still thinking of React as being a framework like jQuery. But React is a framework like Rails or Django. As a developer, it’s where you do all your work. Heck, it’s pretty much your identity. But whereas Rails or Django run on the back end, React runs on the front end …except when it doesn’t. JavaScript can run on the server, which means React can run on the server. It’s entirely possible to have your React cake and eat it. You can write all of your code in React without serving up a single line of React to your users. That’s true in theory. The devil is in the tooling. ### Priorities Next.js and Nuxt allow you to write in React and do server-side rendering. But they really, really want to output React to the client as well. By default, you get the dreaded hydration pattern—do all the computing on the server in JavaScript (yay!), serve up HTML straight away (yay! yay!) …and then serve up all the same JavaScript that’s on the server anyway (ya—wait, what?). It’s possible to get those tools to skip that last step, but it’s not easy. You’ll be battling them every step of the way. Astro takes a very different approach. It will do everything it can to keep the client-side JavaScript to a minimum. Developers get to keep their beloved JSX authoring environment without penalising users. Alas, the collective inertia of the “modern” development community is bound up in the React/Next/Vercel ecosystem. That’s a shame, because Astro shows us that it doesn’t have to be this way. Switching away from using React on the front end doesn’t mean you have to switch away from using React on the back end. ### Why use React? The titular question I asked is too broad and naïve. There are plenty of reasons to use React, just as there are plenty of reasons to use Wordpress, Eleventy, or any other technology that works on the back end. If it’s what you like or what you’re comfortable with, that’s reason enough. All I really care about is the front end. I’m not going to pass judgment on anyone’s choice of server-side framework, as long as it doesn’t impact what you can do in the client. Like Harry says: > …if you’re going to use one, I shouldn’t be able to smell it. Here’s the question I should be asking: Why use React _in the browser_? Because if the reason you’re using React is cultural—the whole team works in JSX, it makes hiring easier—then there’s probably no need to make your users download React. If you’re making a single-page app, then …well, the first thing you should do is ask yourself if it really needs to be a single-page app. They should be the exception, not the default. But if you’re determined to make a single-page app, then I can see why state management becomes very important. In that situation, try shipping Preact instead of React. As a developer, you’ll almost certainly notice no difference, but your users will appreciate the refreshing lack of bloat. Mostly though, I’d encourage you to investigate what you can do with vanilla JavaScript in the browser. I totally get why you’d want to hold on to React as an authoring environment, but don’t let your framework limit what you can do on the front end. If you use React on the client, you’re not doing your users any favours. You can continue to write in React. You can continue to use JSX. You can continue to hire React developers. But keep it on your machine. For your users, make the most of what web browsers can do. Once you keep React on the server, then a whole world of possibilities opens up on the client. Web browsers have become incredibly powerful in what they offer you. Don’t let React-on-the-client hold you back. And if you want to know more about what web browsers are capable of today, come to Web Day Out in Brighton on Thursday, 12th March 2026.
adactio.com
November 26, 2025 at 12:42 PM
Reading The Bloody Chamber And Other Stories by Angela Carter.
November 25, 2025 at 12:21 PM
Thursday session
November 21, 2025 at 9:27 AM
Manuel Matuzovič is speaking at Web Day Out
The line-up for Web Day Out is now complete! The final speaker to be added to the line-up is the one and only Manuel Matuzovič. You may know Manuel from his superb Web Accessibility Cookbook (full disclosure: I had the honour of writing the foreword to that book). Or perhaps you’re familiar with the crimes against markup that he documents at HTMHell. But at Web Day Out, he’s going to be talking about CSS. The past few years have seen a veritable explosion in CSS capabilities. It’s one thing to hear about all the new stuff in CSS, but how do you actually start using it? You may need to unlearn what you have previously learned. That’s what Manuel’s talk will be covering: > Manuel built a new project from scratch with modern CSS and questioned every line of code he wrote. > > In this talk, he presents what he has learned and encourages you to review your best practices. You can see why I’m so excited about this—it’s _perfect_ for the agenda of Web Day Out: > Do you feel like you’re missing out on some of the latest advances in HTML, CSS, and JavaScript APIs? Web Day Out is your chance to get up to speed on what matters. There’ll be eight brilliant speakers for your entertainment: 1. Jemima Abu 2. Rachel Andrew 3. Jake Archibald 4. Aleth Gueguen 5. Manuel Matuzovič 6. Lola Odelola 7. Harry Roberts 8. Richard Rutter You won’t want to miss this, so get your ticket now for the ludicrously reasonable price of just £225+VAT! See you in Brighton on 12 March 2026!
adactio.com
November 20, 2025 at 2:56 PM
Wednesday session
November 19, 2025 at 8:51 PM
Never mind Cloudflare; the electricity has gone out in our street.

It’s actually kinda nice, playing mandolin by candlelight.
November 18, 2025 at 9:27 PM
The premature sheen
I find Brian Eno to be a fascinating chap. His music isn’t my cup of tea, but I really enjoy hearing his thoughts on art, creativity, and culture. I’ve always loved this short piece he wrote about singing with other people. I’ve passed that link onto multiple people who have found a deep joy in singing with a choir: > Singing aloud leaves you with a sense of levity and contentedness. And then there are what I would call “civilizational benefits.” When you sing with a group of people, you learn how to subsume yourself into a group consciousness because a capella singing is all about the immersion of the self into the community. That’s one of the great feelings — to stop being me for a little while and to become us. That way lies empathy, the great social virtue. Then there’s the whole Long Now thing, a phrase that originated with him: > I noticed that this very local attitude to space in New York paralleled a similarly limited attitude to time. Everything was exciting, fast, current, and temporary. Enormous buildings came and went, careers rose and crashed in weeks. You rarely got the feeling that anyone had the time to think two years ahead, let alone ten or a hundred. Everyone seemed to be passing through. It was undeniably lively, but the downside was that it seemed selfish, irresponsible and randomly dangerous. I came to think of this as “The Short Now”, and this suggested the possibility of its opposite - “The Long Now”. I was listening to my Huffduffer feed recently, where I had saved yet another interview with Brian Eno. Sure enough, there was plenty of interesting food for thought, but the bit that stood out to me was relevant to, of all things, prototyping: > I have an architect friend called Rem Koolhaas. He’s a Dutch architect, and he uses this phrase, “the premature sheen.” In his architectural practice, when they first got computers and computers were first good enough to do proper renderings of things, he said everything looked amazing at first. > > You could construct a building in half an hour on the computer, and you’d have this amazing-looking thing, but, he said, “It didn’t help us make good buildings. It helped us make things that looked like they might be good buildings.” > > I went to visit him one day when they were working on a big new complex for some place in Texas, and they were using matchboxes and pens and packets of tissues. It was completely analog, and there was no sense at all that this had any relationship to what the final product would be, in terms of how it looked. > > It meant that what you were thinking about was: How does it work? What do we want it to be like to be in that place? You started asking the important questions again, not: What kind of facing should we have on the building or what color should the stone be? I keep thinking about that insight: “It didn’t help us make good buildings. It helped us make things that looked like they might be good buildings.” Substitute the word “buildings” for whatever output is supposedly being revolutionised by generative models today. Websites. Articles. Public policy.
adactio.com
November 18, 2025 at 11:06 AM
Front page of the BBC right now.
November 18, 2025 at 8:22 AM
Reading The Country Girls by Edna O’Brien.
November 16, 2025 at 11:31 AM
Closing out #ffconf with Erika’s chickens.
November 14, 2025 at 5:34 PM
Closing out #ffconf with Erica’s chickens.
November 14, 2025 at 5:29 PM
Kicking off #ffconf!
November 14, 2025 at 9:53 AM
I’m definitely going to be sent on a side quest.
November 13, 2025 at 5:51 PM
> Technology isn’t destiny, no matter how inexorable its evolution may seem; the way its capabilities are used is as much a matter of cultural choice and historical accident as politics is, or fashion.

— M. Mitchell Waldrop
November 13, 2025 at 5:32 PM
> All I’ve ever wanted from life is a genuinely great SVG vector illustration of a pelican riding a bicycle.

– Simon Willison
November 13, 2025 at 5:25 PM
Hanging out with Coco.
November 13, 2025 at 12:51 PM
Tuesday session
November 11, 2025 at 9:31 PM
Gatehouse
November 10, 2025 at 11:27 PM
Dan, Sue, and Jessica on Brighton beach.
November 9, 2025 at 9:53 AM