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Kamal 2: Thou need not PaaS

from David Heinemeier Hansson [alt+shift+b] in programming

Kamal was our ticket out of the cloud. A simple tool for deploying containerized applications onto our own hardware, without the need for the complexity of something like Kubernetes. Kamal 2 is a huge leap forward for that tool, and it has just shipped.  Now you can deploy multiple applications to the same server, and you can have SSL certificates automatically provisioned via Let's Encrypt. A big compression in complexity, especially when just getting started. Because Kamal isn't just for high-end cloud exits where applications rely on an entire fleet of machines. It's also an excellent option for running a bunch of smaller apps on a single server. Imagine just how you can run on one of those amazing Hetzner EPYC 9454 boxes with 96 threads and 256GB of RAM that they sell for $220/month!  Our move out of the cloud would not has been nearly as smooth or as fast without Kamal. And I'm thrilled we can share such a tool with everyone else who might want to reconsider the cost of Platform-as-a-Service setups. Kamal works great whether you're starting on a cheap $5 VPS, moving onto a fleet of cloud VMs, using dedicated-but-managed servers, or running your own hardware entirely. In fact, it's chief mission is to allow you to move through all those stages of a production deployment without onerous migration costs or delays. We can't have competition in the cloud as long as folks are locked into proprietary or overly-complicated setups that makes moving from one vendor to another a huge hassle and expense. If this sounds at all appetizing, checkout the new Kamal 2 demo, which shows how to deploy a simple Go application (Kamal isn't just for Rails!), how to add another Rails app on the same box, and how to move that Rails app onto a three-machine Hetzner cloud setup. All in under half an hour. Enjoy Kamal 2!
3rd Oct 2024

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More from David Heinemeier Hansson

Pay yourself first

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.

4th Oct 2025 • 27 votes
Thrice charmed at Rails World

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!

6th Sep 2025 • 38 votes
Omarchy is on the move

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.

5th Aug 2025 • 50 votes
Get in losers, we're moving to Linux!

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!

3rd Jul 2025 • 75 votes
Omarchy: Bottling that inspiration before it spoils

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!

2nd Jun 2025 • 75 votes

More in programming

Not everybody is an AI expert - and that’s fine

This post was previously published through my newsletter on November 9, 2026. From time to time, I will republish newsletter issues on my blog here if I think people (and search engines) might benefit from it. If you want to read everything I’ve written once it is posted, I recommend signing up for the newsletter. If you’re doing anything to stay on top of what is happening in the world of software testing and test automation, like browsing or even posting on LinkedIn, which I stopped doing for the foreseeable future, or reading blog posts - my preferred way of keeping up these days, and I highly recommend Dawid Dylowicz’s excellent Software Testing Weekly aggregator mailing list if you prefer longer-form reading, too you’d be thinking that AI has consumed our entire field, and that everybody (or at least those who post or write in public) is an AI expert these days. The reality, though, is far from that. Yes, some people use a lot of AI, even when I would only call a small fraction of them ‘experts’. I definitely do not classify myself as an ‘AI expert’, by the way. A much larger group uses AI on a less frequent basis, and they’re getting some value out of it. Sometimes more, sometimes less. That’s the group I’m probably in. And then there’s a group of people who haven’t really been using a lot of AI at all so far, beyond maybe the odd prompt to ChatGPT or Claude. I don’t have the actual numbers, but I suspect that this group is a lot larger than you would think from browsing your feed or surfing the blogosphere. You just don’t see them, because they’re typically not the people who do a lot of work in public. A few weeks ago, I started working with a small group of testers to teach them how to use AI in their daily work. This work covers both test automation as well as broader software testing tasks, as some of them contribute to automation on a daily basis, but not all of them do. I’m working with them one day per week, on average, for three months, and we’re making small steps towards making AI a more prominent tool in their tool belt. So, what are we working on right now? I’m pulling ideas from my ‘Valuable Feedback, Fast with AI’ course, and so far, we’ve spent some time setting up Claude, going over some important concepts such as context windows, models, tokens, and (of course!) the probabilistic nature of LLMs, and what that means for the results they provide. We have gone through several initial conversations, using Claude to learn more about and review specific user stories, which was an excellent segue into using talking about MCPs and setting up a connection to both Jira and Confluence using the Atlassian MCP. Last week, we also started experimenting with writing straightforward skills to make it easier for Claude to repeat certain actions in a structured way. These actions ranged from reviewing stories and acceptance criteria to refactoring small chunks of code in their (Robot Framework-based) test automation suite. What I loved about this is the avalanche of ideas that popped up in their heads when they saw how easy it was to use Claude. We made a short to-do list of ideas to try out for the next couple of weeks, and I’m looking forward to seeing them getting more confident around using Claude. One thing I have noticed is that their level of comfort around using AI varies quite a bit. Some of them are naturally quite cautious, which means they’ll ask ‘can we really do this?’ and ‘should we really do this?’ frequently before even submitting a single prompt. This is a good habit, I think, but we’ll have to do some work to get them more comfortable with using LLMs, without losing too much of that caution. Others in the group are the opposite: I need to hold them back a little, because otherwise they’ll create a beautiful mess within days, simply because they see so many opportunities to use Claude in their work. That, too, isn’t inherently bad, but I do want to teach them not just how to get the most out of an LLM, but also (more so) how to use AI prudently. Over the next couple of months, we’ll dive deeper into writing better prompts, creating and structuring skills, better context management, and creating and using agents, and probably a few more things, too. I’m looking forward to seeing these people grow more comfortable around using AI in their daily work, and figuring out where AI genuinely adds value and where it doesn’t in their own context. Is there a deeper message in this newsletter? Maybe not, and I’m just happy to tell you about this project, and how it is a great example of a what I call ‘corporate mentoring’, a very efficient way of teaching a small group of engineers new skills, within their own context. But maybe it’s also to show you that, despite what you might see on the Internet, especially those places featuring a lot of self-congratulation (I’m looking at you, LinkedIn), not everybody out there is an AI expert. At least not yet. So, if you feel like you’re ‘behind’ simply because you’re not running at least 17 agents continuously, creating 5400 merge requests per day, know that you’re not alone. Quite far from it, I would say.

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