Full Width 
Shortcuts 
Sign Up 
Log In 
Articles 
Reading List More from David Heinemeier Hansson
There'll always be more emails in need of reply, more meetings to attend, and more updates to read. A person can fill the entire workweek with these tasks over and over again. But to stay sane and sharp, you must pay yourself first by doing the work that actually means something to you. I feel this acutely as someone responsible to employees, customers, followers, and readers. I could do nothing all day but check up on projects, people, and posts, but my brain would quickly check out if it was just doing that. So quite frequently, I just don't. Don't check in, don't check up, and instead dive into the work that checks my own intellectual boxes. Programming for the love of it. Experimenting for the hell of it. Researching for the fun of it. In another age, I might have been tempted to apologize for such privilege, but screw that. Privilege is wonderful. You should do your best to earn more of it. Even if you have to carve it out of the bare rocks around you. Ironically, the best way to do that is also to choose to always pay yourself first, however little at first. By solving your own problems, tickling your own interests, chasing your own curiosity. That's where you'll find the motivation to elevate your talent. To turn interest into competency. And once you've developed some competency, you'll be rewarded with more privilege to build it further. This is the virtuous circle of merit. There'll always be an endless list of work that could be done. You'll never get through it all and onto your own priorities, if you continue to put them at the bottom.
The first Rails World in Amsterdam was a roaring success back in 2023. Tickets sold out in 45 minutes, the atmosphere was electric, and The Rails Foundation set a new standard for conference execution in the Ruby community. So when we decided to return to the Dutch Capital for the third edition of the conference this year, the expectations were towering. And yet, Amanda Perino, our executive director and event organizer extraordinaire, managed to outdo herself, and produced an even better show this year. The venue we returned to was already at capacity the first time around, but Amanda managed to fit a third more attendees by literally using slimmer chairs! And I didn't hear any complaints the folks who had to sit a little closer together in order for more people to enjoy the gathering. The increased capacity didn't come close to satisfy the increased demand, though. This year, tickets sold out in less than two minutes. Crazy. But for the 800+ people who managed to secure a pass, I'm sure it felt worth the refresh-the-website scramble to buy a ticket. And, as in years past, Amanda's recording crew managed to turn around post-production on my keynote in less than 24 hours, so anyone disappointed with missing out on a ticket could at least be in the loop on all the awesome new Rails stuff we were releasing up to and during the conference. Every other session was recorded too, and will soon be on the Rails YouTube channel. You can't stream the atmosphere, the enthusiasm, and the genuine love of Ruby on Rails, though. I was once again blown away by just how many incredible people and stories we have in this ecosystem. From entrepreneurs who've built million (or billion!) dollar businesses on Rails, to programmers who've been around the framework for decades, to people who just picked it up this year. It was a thrill to meet all of them, to take hundreds of selfies, and to talk about Ruby, Rails, and the Omarchy expansion pack for hours on the hallway track! I've basically stopped doing prepared presentations at conferences, but Rails World is the one exception. I really try my best to put on a good show, present the highlights of what we've been working on in the past year at 37signals, and transfer the never-ending enthusiasm I continue to feel for this framework, this programming language, and this ecosystem. True, I may occasionally curse that commitment in the weeks leading up to the conference, but the responsibility is always rewarded during and after the execution with a deep sense of satisfaction. Not everyone is so lucky as I've been to find their life's work early in their career, and see it continue to blossom over the decades. I'm eternally grateful that I have. Of course, there's been ups and downs over the years — nothing is ever just a straight line of excitement up and to the right! — but we're oh-so-clearly on the up-up-up part of that curve at the moment. I don't know whether it's just the wind or the whims, but Rails is enjoying an influx of a new generation of programmers at the moment. No doubt it helps when I get to wax poetically about Ruby for an hour with Lex Fridman in front of an audience of millions. No doubt Shopify's continued success eating the world of ecommerce helps. No doubt the stability, professionalism, and execution from The Rails Foundation is an aid. There are many auxiliary reasons why we're riding a wave at the moment, but key to it all is also that Ruby on Rails is simply really, really good! Next year, with RailsConf finished, it's time to return to the US. Amanda has picked a great spot in Austin, we're planning to dramatically expand the capacity, but I also fully expect that demand will continue to rise, especially in the most prosperous and successful market for Rails. Thanks again to all The Rails Foundation members who believed in the vision for a new institution back in 2022. It looks like a no-brainer to join such a venture now, given the success of Rails World and everything else, but it actually took guts to sign on back then. I approached quite a few companies at that time who could see the value, but couldn't find the courage to support our work, as our industry was still held hostage to a band of bad ideas and terrible ideologies. All that nonsense is thankfully now long gone in the Rails world. We're enjoying a period of peak unity, excitement, progress, and determination to continue to push for end-to-end problem solving, open source, and freedom. I can't tell you how happy it makes me feel when I hear from yet another programmer who credits Ruby on Rails with finding joy and beauty in the writing web applications because of what I started over 22 years ago. It may sound trite, but it's true: It's an honor and a privilege. I hope to carry this meaningful burden for as long as my intellectual legs still let me stand. See you next year in Austin? I hope so!
Omarchy has been improving at a furious pace. Since it was first released on June 26, I've pushed out 18(!) new releases together with a rapidly growing community of collaborators, users, and new-to-Linux enthusiasts. We have about 3,500 early adopters on the Omarchy Discord, 250 pull requests processed, and one heck of an awesome Arch + Hyprland Linux environment to show for it! The latest release is 1.11.0, and it brings an entirely overhauled control menu to the experience. Now everything is controlled through a single, unified system that makes it super fast to operate Omarchy's settings and options through the keyboard. It's exactly the kind of hands-off-the-mouse operation that I've always wanted, and with Linux, I've been able to build it just to my tastes. It's a delight. There's really something special going on in Linux at the moment. Arch has been around for twenty years, but with Hyprland on top, it's been catapulted in front of an entirely new audience. Folks who'd never thought that open source could be able to deliver a desktop experience worth giving up Windows or macOS for. Of course, Linux isn't for everyone. It's still an adventure! An awesome, teach-you-about-computers adventure, but not everyone is into computer adventures. Plenty of people are content with a computer appliance where they never have to look under the hood. All good. Microsoft and Apple have those people covered. But the world is a big place! And in that big place, there are a growing number of computer enthusiasts who've grown very disillusioned with both Microsoft and Apple. Folks who could be enticed to give Linux a look, if the barrier was a little lower and the benefits a little clearer. Those are the folks I'm building Omarchy for.
I've never seen so many developers curious about leaving the Mac and giving Linux a go. Something has really changed in the last few years. Maybe Linux just got better? Maybe powerful mini PCs made it easier? Maybe Apple just fumbled their relationship with developers one too many times? Maybe it's all of it. But whatever the reason, the vibe shift is noticeable. This is why the future is so hard to predict! People have been joking about "The Year of Linux on the Desktop" since the late 90s. Just like self-driving cars were supposed to be a thing back in 2017. And now, in the year of our Lord 2025, it seems like we're getting both! I also wouldn't underestimate the cultural influence of a few key people. PewDiePie sharing his journey into Arch and Hyprland with his 110 million followers is important. ThePrimeagen moving to Arch and Hyprland is important. Typecraft teaching beginners how to build an Arch and Hyprland setup from scratch is important (and who I just spoke to about Omarchy). Gabe Newell's Steam Deck being built on Arch and pushing Proton to over 20,000 compatible Linux games is important. You'll notice a trend here, which is that Arch Linux, a notoriously "difficult" distribution, is at the center of much of this new engagement. Despite the fact that it's been around since 2003! There's nothing new about Arch, but there's something new about the circles of people it's engaging. I've put Arch at the center of Omarchy too. Originally just because that was what Hyprland recommended. Then, after living with the wonders of 90,000+ packages on the community-driven AUR package repository, for its own sake. It's really good! But while Arch (and Hyprland) are having a moment amongst a new crowd, it's also "just" Linux at its core. And Linux really is the star of the show. The perfect, free, and open alternative that was just sitting around waiting for developers to finally have had enough of the commercial offerings from Apple and Microsoft. Now obviously there's a taste of "new vegan sees vegans everywhere" here. You start talking about Linux, and you'll hear from folks already in the community or those considering the move too. It's easy to confuse what you'd like to be true with what is actually true. And it's definitely true that Linux is still a niche operating system on the desktop. Even among developers. Apple and Microsoft sit on the lion's share of the market share. But the mind share? They've been losing that fast. The window is open for a major shift to happen. First gradually, then suddenly. It feels like morning in Linux land!
Over the years, I've learned not to question inspiration. To simply let it drive when it shows up with a full tank. Quite often, I don't exactly know where we're going or even why we're going, but it's repeatedly taken me to just the right place at just the right time, so now I just hop in and say: Let's go! Case in point: Arch + Hyprland. It's been over a year since I created Omakub to smooth out my own exit path from macOS to Linux, and in the process, helped thousands of others enjoy a beautiful, preconfigured, and relatively familiar desktop experience with Ubuntu. And I continue to think this is an excellent choice for Linux, especially for first-time Mac and Windows defectors. But this weekend, I just happened to be home alone, and the hype around Arch + Hyprland got the better of me. While Ubuntu is all about being a friendly place for newcomers to Linux, Arch + Hyprland is the exact opposite: It's Linux on hard mode! At least that's the reputation, and there's certainly something to that. The Arch ISO literally just dumps you into a terminal with scarcely any direction. Just getting on the Wi-Fi requires learning the arcane command-line options for the iwctl terminal configurator. But besides iwctl, it's actually not that bad anymore. We now have a cheat code for installing Arch in the form of archinstall. It's a terminal interface for getting all the bits like picking a disk and creating the first user done in the correct order, without having to set aside an entire evening just to get the OS installed. So it didn't take long to get Arch up and running. That doesn't get you much further, though! By default, Arch is about as minimal as it gets. There's no default graphical interface. There are no niceties. Not even wget or curl by default! It really is just a bare-bones installation of Linux. But on the other hand, Arch is blessed with the AUR — a Wikipedia-style, community-maintained package management system that seems to have literally every piece of software ever released on Linux, and always in the latest version. A quarter of Omakub is trying to work around the fact that helpful tools like Alacritty or LazyGit or whatever rarely have official packages for Ubuntu, so you're left doing a lot of manual scripting to get everything a developer would want from a modern Linux setup. Not so with the AUR! So that's Arch. But Hyprland is even more hilarious. It's a tiling window manager with something as rare in the Linux world as a keen focus on aesthetics! It looks like it was written by visual artists rather than neckbeards. And it's at the core of the modern r/unixporn Linux ricing subculture. That's not the funny part, though. The funny part is how ridiculously atomized the entire thing is. Hyprland comes with absolutely nothing out of the box. No login screen, no menu bar, no notification system, no file manager, no visual settings application. Just a text-based configuration file, a wiki, and an outline on a map for how to design your own adventure. This means that if you're interested in running Hyprland, and you intend to set it all up from scratch, you're probably signing up for at least a good 10+ hours — just to install and configure everything! Now, there are some precompiled setup scripts out there already, but most of them still require you to do a ton of manual legwork before you reach that beautiful summit of a complete system. So while the downside of Arch + Hyprland is that literally every last detail requires you to make a choice and a config file to move on, it's also its upside: you can change EVERYTHING! And the core window tiling magic of Hyprland is one of the most intoxicating ways of using a computer that I've ever experienced. It looks amazing; it feels amazing (if you prefer using a keyboard instead of a mouse!). I've poured hours and hours into this quest over the weekend, and yet I'm still not even done with my first Arch + Hyprland build! My login screen looks like shit. I haven't decided on a final menu bar configuration. But what is working — the basic tiling flow and look — is so nice that the inspiration keeps driving the project forward. Which, of course, I've already decided to codify. I'm not going through all this work to set up a beautiful, preconfigured, fully-functional, out-of-the-box Arch + Hyprland combo and then not share it with anyone who's curious (and might not have 10–20 hours for this kind of side quest available in their schedule). So of course I registered a domain and found a way to draw some ASCII art: Omarchy is on the way!
More in programming
As with my last post on AI, let me open with a statement: Just because most people hold AI a certain way, doesn’t mean that we always must, either now or in the future. As I noted in that piece, and my shades of gray post, I am well aware — and agree with — … Continue reading Must we always use LLMs this way? →
TokyoDev has grown substantially over the past few years. We’ve expanded our community, dramatically increased the scope and frequency of our events, and have curated a library of articles for international developers. Despite all that, the way we run the business hasn’t changed much. I’ve continued to coordinate most of these activities myself, making the final decisions and keeping everything connected. In short, TokyoDev cannot run without my daily input. That approach worked well when TokyoDev was smaller, but it’s increasingly limiting how much we can accomplish. To help the business grow further, I wanted to find someone to take over some of my responsibilities and bring a fresh perspective. This is a significant step for me personally, as while I have worked with many contractors over the years, I have never actually hired a regular employee. Most importantly, I wanted to ensure that this person was someone I could trust to understand what TokyoDev stands for, and to make decisions in line with our philosophy. So I’m happy to announce that Scott Rothrock is joining TokyoDev full time as our Head of Operations. About Scott Scott has lived in Japan for nearly 20 years and has worked as a software engineer in multiple industries and environments, including small Japanese-owned businesses, overseas employers, and international companies based in Japan. Until the end of October 2026, he was the head of the Japan Markets team at Kraken Technologies, where he led an international team of software engineers in delivering complicated, regulated products on strict timelines for Japanese electricity and gas retailers, while also ensuring compliance with evolving organizational and global standards. He’s made a name for himself both inside and outside Japan as a kind, effective mentor who can cultivate great engineers and leaders. Scott’s previous role in TokyoDev Some of you may already know Scott in another capacity, as he has been involved with TokyoDev since 2022. He began as a community volunteer and later became our community manager, which also included responsibilities such as managing our article pipeline from submission to publishing. When I created TokyoDev’s Discord, I had no previous experience running an online community. Scott joined soon after I started and began helping other members, stepping in when people behaved inappropriately, and configuring our roles and permissions and safety features. I was impressed by his initiative and asked him to become an official moderator in January 2023. Outside of his role as a moderator, Scott has always pushed TokyoDev to grow; for example, he arranged internet events such as livestreamed AMAs and interviews. He organized TokyoDev’s first meetup as a volunteer in February 2023, which taught me that there was interest in TokyoDev events outside of the internet. By the end of 2023, I had brought him on as our part-time community manager. What I saw throughout his tenure was that Scott continued to take initiative in expanding TokyoDev. Scott was one of our first external contributors, writing about his experience living with a disability in Japan. He encouraged me to expand and refine both our editing and submission processes so that we could reach out to even more contributors and platform their perspectives. The editorial team now consists of him and Rebecca Callahan, and they’ve had a hand in every article that TokyoDev has published. In other words, since 2022, Scott has shown that he cares about TokyoDev as much as I do. He is invested in what we do and why we do it, and shares my vision for what TokyoDev can become. What changes now Scott’s experiences as an engineer, a mentor, and a leader make me confident that, as our Head of Operations, he will continue to help TokyoDev mature. A big part of what has made TokyoDev successful is that I see the software developers who use our site as my peers and genuinely want to help them. Scott shares that perspective, and will join me in ensuring that TokyoDev remains true to its principles while we grow. So what changes in the short term? Nothing dramatic. I will teach Scott about managing TokyoDev as a business, and he will document our processes and products as a part of that learning. He will also look for areas of improvement while ensuring that we remain compliant with regulations and labor law. Over time, I will hand over some other responsibilities. I will continue to run TokyoDev, but TokyoDev will become less dependent on me for its day-to-day operations. Long term, I’m excited about what this will enable us to do. TokyoDev has always been about helping international software developers build successful careers in Japan, and bringing Scott on full time puts us in a much better position to continue doing that. We look forward to writing the next chapter of TokyoDev together.
Kidz Fun Art is a drawing, colouring and animation app for kids that I’ve been building since 2021. It runs in the browser also as a simple wrapper app on iOS, iPadOS and Windows. It wasn’t getting a great click through rate on Google, even for people who directly searched for it. So, for two days I took a hard look at how fast it loads and how search engines see it. It wasn’t flattering. This post covers what I found, what I changed and what the graphs say now. Short version: on a simulated slow phone, the homepage’s Largest Contentful Paint got about 2.6× faster (15.9 s to 6.1 s) and its first load is about 82% smaller (4.2 MB to 0.75 MB). I also fixed a set of SEO mistakes that are, frankly, embarrassing to write down. I’ll write them down anyway. Part 1: Google had no idea what the site was for I started by reading 16 months of Google Search Console data. 9,380 clicks in total. About 9,200 came from people who had typed “kidz fun art” or a close spelling. People searching for what the app actually does (“coloring app for kids”, “ai art for kids”, “make a comic book”) sent the site 164 clicks. In 16 months. Total. When there was a relevant page, Google ranked it well. The site was #1 for things like “drawing app for kids ipad” and a German query that means “paint by numbers app without ads”. There just weren’t many relevant pages. Then I looked at the code, and the cause was obvious. The homepage <title> was “Kidz Fun Art” in all 12 languages. That’s a fine name, and a terrible title. It tells a search engine nothing. The homepage’s first <h1> was the pricing table’s “Choose your experience”. I was, in effect, telling Google that the most important thing on my homepage was the checkout. Every blog post had the same meta description: a generic line about “news, updates, tips”. Each post’s front matter already had a perfectly good excerpt field that nobody read. Blog posts had two <h1>s: the site header and the post title. There was no structured data at all. The sitemap that redirected every single URL This one stings. The sitemap is the one file whose whole job is to say “here are my URLs, please index them”. Mine listed 17 URLs, and every one of them redirected. The sitemap build used an environment variable that resolved to kidzfun.art. The site lives on www.kidzfun.art, so every URL got a 308. Only the English blog posts were listed. The other 11 languages appeared only as hreflang alternates, which pointed at redirecting URLs too. There were no <link rel="canonical"> tags on any page and no hreflang in the page <head>. Google was left to guess which URL was the real one, and it guessed wrong a lot. What I changed: The sitemap is now built on https://www.kidzfun.art, with 204 URLs: every home page, blog index, blog post, About page and gallery page, in all 12 languages. Each one lists all of its language alternates plus an x-default. A shared SeoLinks component adds an absolute canonical (www, no query string) and the full hreflang set to every public page. The ?v= cache-busting URLs that had been showing up as duplicates now canonicalise to the clean URL. /xx/blog/yy/... URLs, which returned a 500 in production (oops), now 308 to /blog/yy/.... Login, account, debug, export and embed pages send X-Robots-Tag: noindex, follow from next.config.js, so they stop using up crawl budget. robots.txt now mentions the sitemap. Novel idea. Why Google skipped half the site Search Console’s Pages report had 93 of 174 known pages not indexed. Every reason on that list traces back to the mistakes above: “Page with redirect” (22): that sitemap, plus internal links to the non-www host. “Duplicate without user-selected canonical” (18): I hadn’t selected any canonicals. Fair cop. “Crawled, currently not indexed” (39): mostly translated posts that Google reached through redirecting URLs, plus thin pages like /login. “Discovered, currently not indexed” (12): Google found these and decided they weren’t worth a visit. With no sitemap entry and no hreflang, I hadn’t given it a reason to. On-page fixes Titles and descriptions: Each blog post got its own seoTitle and description, in all 12 languages. The meta description now comes from the post’s excerpt, which is what that field was for all along. The About pages take their title and description from their own localized Markdown. They had been sharing an English title and a generic description. One <h1> per page: A # heading inside a post’s Markdown now renders as an <h2>, so the post title is the only <h1>. The About page opts back in with a keepH1 prop. Its Markdown heading is the page title. This fix arrived in two parts. The first part left the About page with zero <h1>s. I noticed, eventually. Structured data and social tags: JSON-LD for the home page (the app), blog posts (articles) and the embedded videos. Open Graph and X/Twitter tags on every public page, so shared links get a proper card. A real 404 for deleted gallery images: The AI gallery shows a friendly “AI Artwork Not Found” page when an image has been deleted. It used to return 200 OK, which Google calls a “soft 404” and dislikes. It now returns a 404 with noindex, and a 503 if the Firestore lookup itself fails, so a database hiccup tells crawlers “come back later” rather than “this is gone”. Part 2: Making the homepage fast The homepage is the app. It works offline, so every dialog (save, stickers, colouring pages, “get an adult”, “no wifi”) is server-rendered into the HTML up front. That’s a deliberate trade-off, and I kept it because I want new users to be able to immediately be able to start drawing as soon as they launch the app. What I hadn’t thought about was what it meant for the network. What the homepage downloaded before the app could start I measured the live site with a Lighthouse-style mobile profile: slow 4G (1.6 Mbps, 150 ms latency), 4× CPU slowdown, empty cache. First load: 4.5 MB over 198 requests. The homepage HTML alone was 358 KB, with about 77 <img> tags in hidden dialogs. The browser dutifully fetched every one of those images. The script that starts the app (main.min.js, 191 KB) sat at the very end of the document, so the browser found it last and gave it whatever bandwidth was left. The app script finished arriving at about 14 seconds. The CPU was not the problem. Every long task was under 300 ms. This was purely about bandwidth and request order. I had built a very polite queue and put my own app at the back of it. Watch the queue The waterfall is a simplified illustration. The milestone times (first paint, LCP, load) are measured: slow 4G + 4× CPU, local production build, median of 3 runs. My Largest Contentful Paint was the “Contact support” link The canvas doesn’t count toward LCP, and the toolbar buttons are small. So on a slow load the largest thing painted was… the loading dialog. The loading dialog fades in its “Taking a while? Contact support” text after 5 to 7.5 seconds. On a slow connection, that text became the page’s LCP element, at 15.9 s. I was measuring my page speed by how long it took to suggest the user complain about my page speed. There’s a lesson in there somewhere. The fix wasn’t to change the dialog. It was to make the app start sooner, so it paints before that text ever appears. What I changed Preload the app script. I added <link rel="preload" as="script"> in <head> for main.min.js and errorHandler.min.js. The <script> tags stay where they were, so execution order doesn’t change. The browser just starts fetching them before any image. This one line did more than anything else on this list. It’s a little humbling. Turn the three dialog GIFs into MP4s. Three animated GIFs: an arrow pushing pictures into a tablet (927 KB), a dancing rainbow pencil (650 KB) and a paper plane (305 KB). That’s 1.9 MB of decoration in dialogs most visitors never open on their first visit. I re-encoded them with ffmpeg: H.264 High profile, -preset veryslow -crf 20, yuv420p, +faststart, constant frame rate taken from each GIF’s frame delay. The commands are committed as scripts/gif-to-mp4.sh. The result is 130 KB in total, with SSIM between 0.988 and 0.993 against the originals. The pencil needed tpad=stop_mode=clone:stop_duration=0.2, because ffmpeg’s GIF reader drops the final 250 ms hold and the dance lost its big finish. The new <video autoplay loop muted playsinline> tags render at exactly the same size and class as the old <img> tags. Alt text moved to aria-label. Locked colouring thumbnails were full-size PNGs. In the colouring page picker, locked pages used the full-size colouring PNG as their background image, inlined into the HTML. That came to about 1.3 MB on every first visit, to draw thumbnails in a dialog that was closed. They now use the small image, set when the picker opens, like the unlocked ones always did. Sticker thumbnails wait their turn. I tried loading="lazy" first. It didn’t help: Chrome fetched the images before the stylesheet that hides the dialogs had arrived, so as far as it knew they were visible. Sticker thumbnails and the media library’s YouTube thumbnail now use data-deferred-src. They load 3 seconds after the load event, or as soon as their dialog opens, whichever comes first. The service worker preload starts after load. The offline preload queue (about 2 MB of colouring pages and stickers) used to start while the page was still loading and compete with it. Now it starts after the load event. Same files, same offline result, no fighting for bandwidth. Analytics is async. Nothing waited for it, so nothing needed to block on it. Cache headers. /images/*: max-age=86400, stale-while-revalidate=604800. It had been max-age=0, so every image was re-checked on every visit. Versioned /js, /css and /addToHomescreen files are immutable for a year in production. Offline still has to work Offline support is a core feature, so “just don’t download it” was never an option. Some of the changes above put it at risk, and a couple of things turned up along the way: Safari plays video from byte ranges. Safari requests video with Range: bytes=.... Answer that with a full cached response and the video won’t play. The service worker now answers Range requests from its cache with a proper 206 Partial Content slice (lib/util/rangeResponse.ts, with unit tests). First-visit gap: on a first visit the service worker isn’t controlling the page yet, so dialog images only reached the offline cache on the second online visit. The page’s own dialog images and videos now go to the front of the offline preload queue on the first visit. I nearly downloaded my whole site, 12 times over. The service worker cached every <link href> it found in the page. The new SEO work had just added canonical and hreflang <link>s pointing at all 12 localized homepages. So every new visitor would have downloaded about 12 extra homepages, in languages they don’t speak, “for offline use”. I caught it before production. The service worker now skips rel=canonical and rel=alternate. Safari stopped the service worker mid-download. The old preload queue ran on timers after the request had been answered. Safari considers an idle service worker fair game, so it stopped it after the first few images. The page now sends images in batches of 10, and the service worker caches each batch before it replies. A page lock-up I’d never noticed. resizeDialog added a new “image loaded” listener every time the window resized. With lots of images loading at once, the listeners multiplied until the page locked up. It now attaches one listener per image, which, in hindsight, is how many it needed. Part 3: The blog Blog index cards used the full 1920 px screenshots as covers, up to 500 KB each, in a box about 200 px wide. Each card was a little billboard, shrunk down by the browser on every visit. Covers now go through next/image with sizes that match the actual card widths, so the browser gets a resized WebP. The first few cards get priority. The rest load lazily. The first sizes hint was too small at some widths and made covers blurry. It now matches the real card widths, up to about 630 px between 769 px and 1028 px wide. Post pages: The cover image gets fetchpriority="high", and images further down the post load lazily. Five images were recompressed in place, keeping the same filenames and dimensions. The PNGs came out about 4× smaller and the JPEGs about 40% smaller. I deleted a 1.1 MB cover.png that nothing referenced. All 12 translations of that post used cover.jpg. The PNG had just been sitting in public/ taking up space. Results on the slow 4G profile: /blog LCP went from 13.3 s to 1.8 s. A typical post went from 3.9 s to 1.7 s. The gallery didn’t get faster, on purpose. It got a 5-minute edge cache and a cached Firestore image count, which fixed its slow server responses. I decided not to change its 20 full-size PNG thumbnails, so its lab LCP barely moved (8.4 s to 8.6 s). That’s a choice, and the chart owns it. Part 4: Lighthouse homework After the speed work went live I ran Lighthouse on the production homepage (mobile) and cleaned up what it flagged. Performance stayed in the low 70s, so I have some more work to do, but it’s moved nicely in the right direction. Part 5: Telling the search engines Fixing the site is half the job. The other half is getting crawlers to come back and notice. Google Search Console: Resubmitted the www sitemap. Clicked “Validate fix” on “Duplicate without user-selected canonical” and on the redirect errors. Requested indexing for the main language homepages and the top blog posts. The quota is about 10 a day, so it’ll take a few days. Wrote down a baseline from the Performance report, so in 4 to 8 weeks I can tell whether any of this worked. Bing Webmaster Tools: Submitted all 204 sitemap URLs through URL Submission. The daily quota is 10,000, so no trickle-feeding needed. Bing’s index also feeds DuckDuckGo and several AI search tools, so it’s cheap extra reach. Most of Bing’s “SEO recommendations” pointed at old ?v= URLs and old titles. They’ll clear as Bing recrawls. What I’m not watching: the Lighthouse score. Google ranks on real-user Chrome data (the Chrome UX Report): a rolling 28-day window, judged at the 75th percentile. So the honest answer to “did it work?” is “ask me in a month”. How I kept from breaking things The app has hundreds of unit and integration tests, all of which still pass (even though they do take over 30 minutes to run). I also manually regression tested all the riskiest changes. Hopefully I don’t make things worse before they get better… Lessons, mostly at my own expense Read your own sitemap. Actually open it and click a URL. Mine had been quietly redirecting for who knows how long. <link rel="preload"> for the script that boots your app is the cheapest big win there is. Browsers fetch resources in the order they find them. If your app script is at the bottom of a 358 KB document full of images, it really is last in line. Check what your LCP element actually is before you try to make it faster. Mine was a “Contact support” link. GIF is an image format from 1987 that I was using as a video format. A real video codec beats it by an order of magnitude at the same quality. try/catch doesn’t catch promise rejections. I knew that. My code didn’t. Every <link> you add to <head> is something your service worker might decide to download. Speed scores are for diagnosis. Rankings come from real users. Fix what the lab finds, then wait for the field data. Epilogue You’re still here? Wow. Cool. After all this, I’m hoping that users notice nothing other than quicker app start times. I’m looking forward to keeping an eye on traffic and retention in the coming weeks. Wish me luck!
Five months ago, we rebuilt our warehouse on DuckDB instead of ClickHouse. We did it because a shared ClickHouse cluster couldn't handle hours-long…
