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Installing OpenBSD on Linveo KVM VPS 2024-10-21 I recently came across an amazing deal for a VPS on Linveo. For just $15 a year they provide: AMD KVM 1GB 1024 MB RAM 1 CPU Core 25 GB NVMe SSD 2000 GB Bandwidth It’s a pretty great deal and I suggest you look more into it if you’re interested! But this post is more focused on setting up OpenBSD via the custom ISO option in the KVM dashboard. Linveo already provides several Linux OS options, along with FreeBSD by default (which is great!). Since there is no OpenBSD template we need to do things manually. Getting Started Once you have your initial VPS up and running, login to the main dashboard and navigate to the Media tab. Under CD/DVD-ROM you’ll want to click “Custom CD/DVD” and enter the direct link to the install76.iso: https://cdn.openbsd.org/pub/OpenBSD/7.6/amd64/install76.iso The "Media" tab of the Linveo Dashboard. Use the official ISO link and set the Boot Order to CD/DVD. Select “Insert”, then set your Boot Order to CD/DVD and click “Apply”. Once complete, Restart your server. Installing via VNC With the server rebooting, jump over to Options and click on “Browser VNC” to launch the web-based VNC client. From here we will boot into the OpenBSD installer and get things going! Follow the installer as you normally would when installing OpenBSD (if you’re unsure, I have a step-by-step walkthrough) until you reach the IPv4 selection. At this point you will want to input your servers IPv4 and IPv6 IPs found under your Network section of your dashboard. Next you will want to set the IPv6 route to first default listed option (not “none”). After that is complete, choose cd0 for your install media (don’t worry about http yet). Continue with the rest of the install (make users if desired, etc) until it tells you to reboot the machine. Go back to the Linveo Dashboard, switch your Boot Order back to “Harddrive” and reboot the machine directly. Booting into OpenBSD Load into the VNC client again. If you did everything correctly you should be greeted with the OpenBSD login prompt. There are a few tweaks we still need to make, so login as the root user. Remember how we installed our sets directly from the cd0? We’ll want to change that. Since we are running OpenBSD “virtually” through KVM, our target network interface will be vio0. Edit the /etc/hostname.vio0 file and add the following: dhcp !route add default <your_gateway_ip> The <your_gateway_ip> can be found under the Network tab of your dashboard. The next file we need to tweak is /etc/resolv.conf. Add the following to it: nameserver 8.8.8.8 nameserver 1.1.1.1 These nameservers are based on your selected IPs under the Resolvers section of Network in the Linveo dashboard. Change these as you see fit, so long as they match what you place in the resolve.conf file. Finally, the last file we need to edit is /etc/pf.conf. Like the others, add the following: pass out proto { tcp, udp } from any to any port 53 Final Stretch Now just reboot the server. Log back in as your desired user and everything should be working as expected! You can perform a simple test to check: ping openbsd.org This should work - meaning your network is up and running! Now you’re free to enjoy the beauty that is OpenBSD.
Vertical Tabs in Safari 2024-09-26 I use Firefox as my main browser (specifically the Nightly build) which has vertical tabs built-in. There are instances where I need to use Safari, such as debugging or testing iOS devices, and in those instances I prefer to have a similar experience to that of Firefox. Luckily, Apple has finally made it fairly straight forward to do so. Click the Sidebar icon in the top left of the Safari browser Right click and group your current tab(s) (I normally name mine something uninspired like “My Tabs” or simply “Tabs”) For an extra “clean look”, remove the horizontal tabs by right clicking the top bar, selected Customize Toolbar and dragging the tabs out When everything is set properly, you’ll have something that looks like this: One minor drawback is not having access to a direct URL input, since we have removed the horizontal tab bar altogether. Using a set of curated bookmarks could help avoid the need for direct input, along with setting our new tab page to DuckDuckGo or any other search engine.
Build and Deploy Websites Automatically with Git 2024-09-20 I recently began the process of setting up my self-hosted1 cgit server as my main code forge. Updating repos via cgit on NearlyFreeSpeech on its own has been simple enough, but it lacked the “wow-factor” of having some sort of automated build process. I looked into a bunch of different tools that I could add to my workflow and automate deploying changes. The problem was they all seemed to be fairly bloated or overly complex for my needs. Then I realized I could simply use post-receive hooks which were already built-in to git! You can’t get more simple than that… So I thought it would be best to document my full process. These notes are more for my future self when I inevitably forget this, but hopefully others can benefit from it! Before We Begin This “tutorial” assumes that you already have a git server setup. It shouldn’t matter what kind of forge you’re using, so long as you have access to the hooks/ directory and have the ability to write a custom post-receive script. For my purposes I will be running standard git via the web through cgit, hosted on NearlyFreeSpeech (FreeBSD based). Overview Here is a quick rundown of what we plan to do: Write a custom post-receive script in the repo of our choice Build and deploy our project when a remote push to master is made Nothing crazy. Once you get the hang of things it’s really simple. Prepping Our Servers Before we get into the nitty-gritty, there are a few items we need to take care of first: Your main git repo needs ssh access to your web hosting (deploy) server. Make sure to add your public key and run a connection test first (before running the post-receive hook) in order to approve the “fingerprinting”. You will need to git clone your main git repo in a private/admin area of your deploy server. In the examples below, mine is cloned under /home/private/_deploys Once you do both of those tasks, continue with the rest of the article! The post-receive Script I will be using my own personal website as the main project for this example. My site is built with wruby, so the build instructions are specific to that generator. If you use Jekyll or something similar, you will need to tweak those commands for your own purposes. Head into your main git repo (not the cloned one on your deploy server), navigate under the hooks/ directory and create a new file named post-receive containing the following: #!/bin/bash # Get the branch that was pushed while read oldrev newrev ref do branch=$(echo $ref | cut -d/ -f3) if [ "$branch" == "master" ]; then echo "Deploying..." # Build on the remote server ssh user@deployserver.net << EOF set -e # Stop on any error cd /home/private/_deploys/btxx.org git pull origin master gem install 'kramdown:2.4.0' 'rss:0.3.0' make build rsync -a build/* ~/public/btxx.org/ EOF echo "Build synced to the deployment server." echo "Deployment complete." fi done Let’s break everything down. First we check if the branch being pushed to the remote server is master. Only if this is true do we proceed. (Feel free to change this if you prefer something like production or deploy) if [ "$branch" == "master" ]; then Then we ssh into the server (ie. deployserver.net) which will perform the build commands and also host these built files. ssh user@deployserver.net << EOF Setting set -e ensures that the script stops if any errors are triggered. set -e # Stop on any error Next, we navigate into the previously mentioned “private” directory, pull the latest changes from master, and run the required build commands (in this case installing gems and running make build) cd /home/private/_deploys/btxx.org git pull origin master gem install 'kramdown:2.4.0' 'rss:0.3.0' make build Finally, rsync is run to copy just the build directory to our public-facing site directory. rsync -a build/* ~/public/btxx.org/ With that saved and finished, be sure to give this file proper permissions: chmod +x post-receive That’s all there is to it! Time to Test! Now make changes to your main git project and push those up into master. You should see the post-receive commands printing out into your terminal successfully. Now check out your website to see the changes. Good stuff. Still Using sourcehut My go-to code forge was previously handled through sourcehut, which will now be used for mirroring my repos and handling mailing lists (since I don’t feel like hosting something like that myself - yet!). This switch over was nothing against sourcehut itself but more of a “I want to control all aspects of my projects” mentality. I hope this was helpful and please feel free to reach out with suggestions or improvements! By self-hosted I mean a NearlyFreeSpeech instance ↩
“This Key is Useless Now. Discard?” 2024-08-28 The title of this article probably triggers nostalgic memories for old school Resident Evil veterans like myself. My personal favourite in the series (not that anyone asked) was the original, 1998 version of Resident Evil 2 (RE2). I believe that game stands the test of time and is very close to a masterpiece. The recent remake lost a lot of the charm and nuance that made the original so great, which is why I consistently fire up the PS1 version on my PS2 Slim. Resident Evil 2 (PS1) running on my PS2, hooked up to my Toshiba CRT TV. But the point of this post isn’t to gush over RE2. Instead I would like to discuss how well RE2 handled its interface and user experience across multiple in-game systems. HUD? What HUD? Just like the first Resident Evil that came before it, RE2 has no in-game HUD (heads-up display) to speak of. It’s just your playable character and the environment. No ammo-counters. No health bars. No “quest” markers. Nothing. This is how the game looks while you play. Zero HUD elements. The game does provide you with an inventory system, which holds your core items, weapons and notes you find along your journey. Opening up this sub-menu allows you to heal, reload weapons, combine objects or puzzle items, or read through previously collected documents. Not only is this more immersive (HUDs don’t exist for us in the real world, we need to look through our packs as well…) it also gets out of the way. The main inventory screen. Shows everything you need to know, only when you need it. (I can hear this screenshot...) I don’t need a visual element in the bottom corner showing me a list of “items” I can cycle through. I don’t want an ammo counter cluttering up my screen with information I only need to see in combat or while manually reloading. If those are pieces of information I need, I’ll explicitly open and look for it. Don’t make assumptions about what is important to me on screen. Capcom took this concept of less visual clutter even further in regards to maps and the character health status. Where We’re Going, We Don’t Need Roads Mini-Maps A great deal of newer games come pre-packaged with a mini-map on the main interface. In certain instances this works just fine, but most are 100% UI clutter. Something to add to the screen. I can only assume some devs believe it is “helpful”. Most times it’s simply a distraction. Thank goodness most games allow you to disable them. As for RE2, you collect maps throughout your adventure and, just like most other systems in the game, you need to consciously open the map menu to view them. You know, just like in real life. This creates a higher tension as well, since you need to constantly reference your map (on initial playthroughs) to figure out where the heck to go. You feel the pressure of someone frantically pulling out a physical map and scanning their surroundings. It also helps the player build a mental model in their head, thus providing even more of that sweet, sweet immersion. The map of the Raccoon City Police Station. No Pain, No Gain The game doesn’t display any health bar or player status information. In order to view your current status (symbolized by “Fine”, “Caution” or “Danger”) you need to open your inventory screen. From here you can heal yourself (if needed) and see the status type change in real-time. The "condition" health status. This is fine. But that isn’t the only way to visually see your current status. Here’s a scenario: you’re traveling down a hallway, turn a corner and run right into the arms of a zombie. She takes a couple good bites out of your neck before you push her aside. You unload some handgun rounds into her and down she goes. As you run over her body she reaches out and chomps on your leg as a final “goodbye”. You break free and move along but notice something different in your character’s movement - they’re holding their stomach and limping. Here we can see the character "Hunk" holding his stomach and limping, indicating an injury without the need for a custom HUD element. If this was your first time playing, most players would instinctively open the inventory menu, where their characters health is displayed, and (in this instance) be greeted with a “Caution” status. This is another example of subtle UX design. I don’t need to know the health status of my character until an action is required (in this example: healing). The health system is out of the way but not hidden. This keeps the focus on immersion, not baby-sitting the game’s interface. A Key to Every Lock Hey! This section is in reference to the title of the article. We made it! …But yes, discarding keys in RE2 is a subtle example of fantastic user experience. As a player, I know for certain this key is no longer needed. I can safely discard it and free up precious space from my inventory. There is also a sense of accomplishment, a feeling of “I’ve completed a task” or an internal checkbox being ticked. Progress has been made! Don’t overlook how powerful of a interaction this little text prompt is. Ask any veteran of the series and they will tell you this prompt is almost euphoric. The game's prompt asking if you'd like to discard a useless key. Perfection. Inspiring Greatness RE2 is certainly not the first or last game to implement these “minimal” game systems. A more “modern” example is Dead Space (DS), along with its very faithful remake. In DS the character’s health is displayed directly on the character model itself, and a similar inventory screen is used to manage items. An ammo-counter is visible but only when the player aims their weapon. Pretty great stuff and another masterpiece of survival horror. In Dead Space, the character's health bar is set as part of their spacesuit. The Point I guess my main takeaway is that designers and developers should try their best to keep user experience intuitive. I know that sounds extremely generic but it is a lot more complex than one might think. Try to be as direct as possible while remaining subtle. It’s a delicate balance but experiences like RE2 show us it is attainable. I’d love to talk more, but I have another play-through of RE2 to complete…
More in programming
I always had a diffuse idea of why people are spending so much time and money on amateur radio. Once I got my license and started to amass radios myself, it became more clear.
What does it mean when someone writes that a programming language is “strongly typed”? I’ve known for many years that “strongly typed” is a poorly-defined term. Recently I was prompted on Lobsters to explain why it’s hard to understand what someone means when they use the phrase. I came up with more than five meanings! how strong? The various meanings of “strongly typed” are not clearly yes-or-no. Some developers like to argue that these kinds of integrity checks must be completely perfect or else they are entirely worthless. Charitably (it took me a while to think of a polite way to phrase this), that betrays a lack of engineering maturity. Software engineers, like any engineers, have to create working systems from imperfect materials. To do so, we must understand what guarantees we can rely on, where our mistakes can be caught early, where we need to establish processes to catch mistakes, how we can control the consequences of our mistakes, and how to remediate when somethng breaks because of a mistake that wasn’t caught. strong how? So, what are the ways that a programming language can be strongly or weakly typed? In what ways are real programming languages “mid”? Statically typed as opposed to dynamically typed? Many languages have a mixture of the two, such as run time polymorphism in OO languages (e.g. Java), or gradual type systems for dynamic languages (e.g. TypeScript). Sound static type system? It’s common for static type systems to be deliberately unsound, such as covariant subtyping in arrays or functions (Java, again). Gradual type systems migh have gaping holes for usability reasons (TypeScript, again). And some type systems might be unsound due to bugs. (There are a few of these in Rust.) Unsoundness isn’t a disaster, if a programmer won’t cause it without being aware of the risk. For example: in Lean you can write “sorry” as a kind of “to do” annotation that deliberately breaks soundness; and Idris 2 has type-in-type so it accepts Girard’s paradox. Type safe at run time? Most languages have facilities for deliberately bypassing type safety, with an “unsafe” library module or “unsafe” language features, or things that are harder to spot. It can be more or less difficult to break type safety in ways that the programmer or language designer did not intend. JavaScript and Lua are very safe, treating type safety failures as security vulnerabilities. Java and Rust have controlled unsafety. In C everything is unsafe. Fewer weird implicit coercions? There isn’t a total order here: for instance, C has implicit bool/int coercions, Rust does not; Rust has implicit deref, C does not. There’s a huge range in how much coercions are a convenience or a source of bugs. For example, the PHP and JavaScript == operators are made entirely of WAT, but at least you can use === instead. How fancy is the type system? To what degree can you model properties of your program as types? Is it convenient to parse, not validate? Is the Curry-Howard correspondance something you can put into practice? Or is it only capable of describing the physical layout of data? There are probably other meanings, e.g. I have seen “strongly typed” used to mean that runtime representations are abstract (you can’t see the underlying bytes); or in the past it sometimes meant a language with a heavy type annotation burden (as a mischaracterization of static type checking). how to type So, when you write (with your keyboard) the phrase “strongly typed”, delete it, and come up with a more precise description of what you really mean. The desiderata above are partly overlapping, sometimes partly orthogonal. Some of them you might care about, some of them not. But please try to communicate where you draw the line and how fuzzy your line is.
(Last week's newsletter took too long and I'm way behind on Logic for Programmers revisions so short one this time.1) In classical logic, two operators F/G are duals if F(x) = !G(!x). Three examples: x || y is the same as !(!x && !y). <>P ("P is possibly true") is the same as ![]!P ("not P isn't definitely true"). some x in set: P(x) is the same as !(all x in set: !P(x)). (1) is just a version of De Morgan's Law, which we regularly use to simplify boolean expressions. (2) is important in modal logic but has niche applications in software engineering, mostly in how it powers various formal methods.2 The real interesting one is (3), the "quantifier duals". We use lots of software tools to either find a value satisfying P or check that all values satisfy P. And by duality, any tool that does one can do the other, by seeing if it fails to find/check !P. Some examples in the wild: Z3 is used to solve mathematical constraints, like "find x, where f(x) >= 0. If I want to prove a property like "f is always positive", I ask z3 to solve "find x, where !(f(x) >= 0), and see if that is unsatisfiable. This use case powers a LOT of theorem provers and formal verification tooling. Property testing checks that all inputs to a code block satisfy a property. I've used it to generate complex inputs with certain properties by checking that all inputs don't satisfy the property and reading out the test failure. Model checkers check that all behaviors of a specification satisfy a property, so we can find a behavior that reaches a goal state G by checking that all states are !G. Here's TLA+ solving a puzzle this way.3 Planners find behaviors that reach a goal state, so we can check if all behaviors satisfy a property P by asking it to reach goal state !P. The problem "find the shortest traveling salesman route" can be broken into some route: distance(route) = n and all route: !(distance(route) < n). Then a route finder can find the first, and then convert the second into a some and fail to find it, proving n is optimal. Even cooler to me is when a tool does both finding and checking, but gives them different "meanings". In SQL, some x: P(x) is true if we can query for P(x) and get a nonempty response, while all x: P(x) is true if all records satisfy the P(x) constraint. Most SQL databases allow for complex queries but not complex constraints! You got UNIQUE, NOT NULL, REFERENCES, which are fixed predicates, and CHECK, which is one-record only.4 Oh, and you got database triggers, which can run arbitrary queries and throw exceptions. So if you really need to enforce a complex constraint P(x, y, z), you put in a database trigger that queries some x, y, z: !P(x, y, z) and throws an exception if it finds any results. That all works because of quantifier duality! See here for an example of this in practice. Duals more broadly "Dual" doesn't have a strict meaning in math, it's more of a vibe thing where all of the "duals" are kinda similar in meaning but don't strictly follow all of the same rules. Usually things X and Y are duals if there is some transform F where X = F(Y) and Y = F(X), but not always. Maybe the category theorists have a formal definition that covers all of the different uses. Usually duals switch properties of things, too: an example showing some x: P(x) becomes a counterexample of all x: !P(x). Under this definition, I think the dual of a list l could be reverse(l). The first element of l becomes the last element of reverse(l), the last becomes the first, etc. A more interesting case is the dual of a K -> set(V) map is the V -> set(K) map. IE the dual of lived_in_city = {alice: {paris}, bob: {detroit}, charlie: {detroit, paris}} is city_lived_in_by = {paris: {alice, charlie}, detroit: {bob, charlie}}. This preserves the property that x in map[y] <=> y in dual[x]. And after writing this I just realized this is partial retread of a newsletter I wrote a couple months ago. But only a partial retread! ↩ Specifically "linear temporal logics" are modal logics, so "eventually P ("P is true in at least one state of each behavior") is the same as saying !always !P ("not P isn't true in all states of all behaviors"). This is the basis of liveness checking. ↩ I don't know for sure, but my best guess is that Antithesis does something similar when their fuzzer beats videogames. They're doing fuzzing, not model checking, but they have the same purpose check that complex state spaces don't have bugs. Making the bug "we can't reach the end screen" can make a fuzzer output a complete end-to-end run of the game. Obvs a lot more complicated than that but that's the general idea at least. ↩ For CHECK to constraint multiple records you would need to use a subquery. Core SQL does not support subqueries in check. It is an optional database "feature outside of core SQL" (F671), which Postgres does not support. ↩
Omarchy 2.0 was released on Linux's 34th birthday as a gift to perhaps the greatest open-source project the world has ever known. Not only does Linux run 95% of all servers on the web, billions of devices as an embedded OS, but it also turns out to be an incredible desktop environment! It's crazy that it took me more than thirty years to realize this, but while I spent time in Apple's walled garden, the free software alternative simply grew better, stronger, and faster. The Linux of 2025 is not the Linux of the 90s or the 00s or even the 10s. It's shockingly more polished, capable, and beautiful. It's been an absolute honor to celebrate Linux with the making of Omarchy, the new Linux distribution that I've spent the last few months building on top of Arch and Hyprland. What began as a post-install script has turned into a full-blown ISO, dedicated package repository, and flourishing community of thousands of enthusiasts all collaborating on making it better. It's been improving rapidly with over twenty releases since the premiere in late June, but this Version 2.0 update is the biggest one yet. If you've been curious about giving Linux a try, you're not afraid of an operating system that asks you to level up and learn a little, and you want to see what a totally different computing experience can look and feel like, I invite you to give it a go. Here's a full tour of Omarchy 2.0.
In 2020, Apple released the M1 with a custom GPU. We got to work reverse-engineering the hardware and porting Linux. Today, you can run Linux on a range of M1 and M2 Macs, with almost all hardware working: wireless, audio, and full graphics acceleration. Our story begins in December 2020, when Hector Martin kicked off Asahi Linux. I was working for Collabora working on Panfrost, the open source Mesa3D driver for Arm Mali GPUs. Hector put out a public call for guidance from upstream open source maintainers, and I bit. I just intended to give some quick pointers. Instead, I bought myself a Christmas present and got to work. In between my university coursework and Collabora work, I poked at the shader instruction set. One thing led to another. Within a few weeks, I drew a triangle. In 3D graphics, once you can draw a triangle, you can do anything. Pretty soon, I started work on a shader compiler. After my final exams that semester, I took a few days off from Collabora to bring up an OpenGL driver capable of spinning gears with my new compiler. Over the next year, I kept reverse-engineering and improving the driver until it could run 3D games on macOS. Meanwhile, Asahi Lina wrote a kernel driver for the Apple GPU. My userspace OpenGL driver ran on macOS, leaving her kernel driver as the missing piece for an open source graphics stack. In December 2022, we shipped graphics acceleration in Asahi Linux. In January 2023, I started my final semester in my Computer Science program at the University of Toronto. For years I juggled my courses with my part-time job and my hobby driver. I faced the same question as my peers: what will I do after graduation? Maybe Panfrost? I started reverse-engineering of the Mali Midgard GPU back in 2017, when I was still in high school. That led to an internship at Collabora in 2019 once I graduated, turning into my job throughout four years of university. During that time, Panfrost grew from a kid’s pet project based on blackbox reverse-engineering, to a professional driver engineered by a team with Arm’s backing and hardware documentation. I did what I set out to do, and the project succeeded beyond my dreams. It was time to move on. What did I want to do next? Finish what I started with the M1. Ship a great driver. Bring full, conformant OpenGL drivers to the M1. Apple’s drivers are not conformant, but we should strive for the industry standard. Bring full, conformant Vulkan to Apple platforms, disproving the myth that Vulkan isn’t suitable for Apple hardware. Bring Proton gaming to Asahi Linux. Thanks to Valve’s work for the Steam Deck, Windows games can run better on Linux than even on Windows. Why not reap those benefits on the M1? Panfrost was my challenge until we “won”. My next challenge? Gaming on Linux on M1. Once I finished my coursework, I started full-time on gaming on Linux. Within a month, we shipped OpenGL 3.1 on Asahi Linux. A few weeks later, we passed official conformance for OpenGL ES 3.1. That put us at feature parity with Panfrost. I wanted to go further. OpenGL (ES) 3.2 requires geometry shaders, a legacy feature not supported by either Arm or Apple hardware. The proprietary OpenGL drivers emulate geometry shaders with compute, but there was no open source prior art to borrow. Even though multiple Mesa drivers need geometry/tessellation emulation, nobody did the work to get there. My early progress on OpenGL was fast thanks to the mature common code in Mesa. It was time to pay it forward. Over the rest of the year, I implemented geometry/tessellation shader emulation. And also the rest of the owl. In January 2024, I passed conformance for the full OpenGL 4.6 specification, finishing up OpenGL. Vulkan wasn’t too bad, either. I polished the OpenGL driver for a few months, but once I started typing a Vulkan driver, I passed 1.3 conformance in a few weeks. What remained was wiring up the geometry/tessellation emulation to my shiny new Vulkan driver, since those are required for Direct3D. Et voilà, Proton games. Along the way, Karol Herbst passed OpenCL 3.0 conformance on the M1, running my compiler atop his “rusticl” frontend. Meanwhile, when the Vulkan 1.4 specification was published, we were ready and shipped a conformant implementation on the same day. After that, I implemented sparse texture support, unlocking Direct3D 12 via Proton. …Now what? Ship a great driver? Check. Conformant OpenGL 4.6, OpenGL ES 3.2, and OpenCL 3.0? Check. Conformant Vulkan 1.4? Check. Proton gaming? Check. That’s a wrap. We’ve succeeded beyond my dreams. The challenges I chased, I have tackled. The drivers are fully upstream in Mesa. Performance isn’t too bad. With the Vulkan on Apple myth busted, conformant Vulkan is now coming to macOS via LunarG’s KosmicKrisp project building on my work. Satisfied, I am now stepping away from the Apple ecosystem. My friends in the Asahi Linux orbit will carry the torch from here. As for me? Onto the next challenge!
