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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 ↩
Burning & Playing PS2 Games without a Modded Console 2024-09-02 Important: I do not support pirating or obtaining illegal copies of video games. This process should only be used to copy your existing PS2 games for backup, in case of accidental damage to the original disc. Requirements Note: This tutorial is tailored towards macOS users, but most things should work similar on Windows or Linux. You will need: An official PS2 game disc (the one you wish to copy) A PS2 Slim console An Apple device with a optical DVD drive (or a portable USB DVD drive) Some time and a coffee! (or tea) Create an ISO Image of Your PS2 Disc: Insert your PS2 disc into your optical drive. Open Disk Utility (Applications > Utilities) In Disk Utility, select your PS2 disc from the sidebar Click on the File menu, then select New Image > Image from [Disc Name] Choose a destination to save the ISO file and select the format as DVD/CD Master Name your file and click Save. Disk Utility will create a .cdr file, which is essentially an ISO file Before we move on, we will need to convert that newly created cdr file into ISO. Navigate to the directory where the .cdr file is located and use the hdiutil command to convert the .cdr file to an ISO file: hdiutil convert yourfile.cdr -format UDTO -o yourfile.iso You’ll end up with a file named yourfile.iso.cdr. Rename it by removing the .cdr extension to make it an .iso file: mv yourfile.iso.cdr yourfile.iso Done and done. Getting Started For Mac and Linux users, you will need to install Wine in order to run the patcher: # macOS brew install wine-stable # Linux (Debian) apt install wine Clone & Run the Patcher Clone the FreeDVDBoot ESR Patcher: git clone https://git.sr.ht/~bt/fdvdb-esr Navigate to the cloned project folder: cd /path/to/fdvdb-esr The run the executable: wine FDVDB_ESR_Patcher.exe Now you need to select your previously cloned ISO file, use the default Payload setting and then click Patch!. After a few seconds your file should be patched. Burning Our ISO to DVD It’s time for the main event! Insert a blank DVD-R into your disc drive and mount it. Then right click on your patched ISO file and run “Burn Disk Image to Disc...". From here, you want to make sure you select the slowest write speed and enable verification. Once the file is written to the disc and verified (verification might fail - it is safe to ignore) you can remove the disc from the drive. Before Playing the Game Make sure you change the PS2 disc speed from Standard to Fast in the main “Browser” setting before you put the game into your console. After that, enjoy playing your cloned PS2 game!
“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…
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I’ve never published an essay quite like this. I’ve written about my life before, reams of stuff actually, because that’s how I process what I think, but never for public consumption. I’ve been pushing myself to write more lately because my co-authors and I have a whole fucking book to write between now and October. […]
Less known desktop UI frameworks Writing desktop software is hard. The UI technologies of Windows or MacOS are awful compared to web technology. What can trivially be done with HTML/CSS/JavaScript in few minutes can take hours using Windows’s win32 APIs or Mac’s Cocoa. That’s why the default technology for desktop apps, especially cross-platform, is Electron: a Chrome browser combined with Node runtime. The problem is that it’s bloaty: each app is a unique build of Chrome with a little bit of application code. Chrome is over 100MB so many apps ship less than 1MB of code in a 100M wrapper. People tried to address the problem of poor OS APIs by writing UI frameworks, often meant to be cross-platform. You’ve heard about QT, GTK, wxWindows. The problem with those is that they are also old, their APIs are not the greatest either and they are bloaty as well. There just doesn’t seem to be a good option. Writing your own framework seems impossible due to the size of task. But is it? I’ll show a couple of less-known UI frameworks written mostly be a single person, often done simply to enable writing an application. SWELL in WDL WDL is interesting. Justin Frankel, the guy who created Winamp, has a repository of C++ code he uses in different projects. After selling Winamp to AOL, a side quest of writing file sharing application, getting fired from AOL for writing file sharing application, he started a company building Reaper a digital audio workstation software for Windows. Winamp is a win32 API program and so is Reaper. At some point Justin decided to make a Mac version but by then he had a lot of code heavily using win32 APIs. So he did what anyone in his position would: he implemented win32 APIs for Mac OS and Linux and called it SWELL - Simple Windows Emulation Layer. Ok, actually no-one else would do it. It was an insane idea but it worked. It’s important to not over-state SWELL capabilities. It’s not Wine. You can’t take any win32 program and recompile for Mac with SWELL. Frankel is insanely pragmatic and so is his code. SWELL only implements the subset of APIs he uses in Reaper. At the same time Reaper is a big app so if SWELL works for Reaper, it could work for your app. WDL is open-source using permissive MIT license. Sublime Text For a few years Sublime Text was THE programmer’s editor. It was written by a single developer in C++ and he wrote a custom UI toolkit for it. Not open source but its existence shows it can be done. RAD Debugger RAD Debugger is an open-source Windows debugger for C/C++ apps written in C by mostly a single person. It implements a custom UI framework based on 3D renderer. The UI is integral part of the the app but the code is well structured so you probably can take just their UI / render code and use it in your own C / C++ app. Currently the app / UI is only for Windows but it’s designed to be cross-platform and they are working on porting the renderer to Mac OS / Linux. They use permissive MIT license and everything is written in C. Dear ImGUI Dear ImGui is a newer cross-platform, UI framework in C++. Open source, permissive MIT license. Written by mostly a single person. Ghostty Ghostty is a cross-platform terminal emulator and UI. It’s written in Zig by mostly a single person and uses it’s own low-level GPU renderer for the UI. You too can write your own UI framework At first the idea of writing your own UI framework seems impossibly daunting. What I’m hoping to show is that if you’re ambitious enough it’s possible to build cross platform desktop apps that are not just bloated 100MB Chrome wrappers around few kilobytes of custom code. I’m not saying it’s a simple thing, just that enough people did it that it’s possible. It shouldn’t be necessary but both Microsoft and Apple have tragically dropped the ball on providing decent, high-performance UI libraries for their OS. Microsoft even writes their own apps, like Teams, in web technologies. Thanks to open source you’re not at the staring line. You can just use Dear ImGUI or WDL’s SWELL. Or you can extract the UI code from RAD Debugger or Ghostty (if you write in Zig). Or you can look at how their implementation to speed up your own design and implementation.
I released Logic for Programmers exactly one year ago today. It feels weird to celebrate the anniversary of something that isn't 1.0 yet, but software projects have a proud tradition of celebrating a dozen anniversaries before 1.0. I wanted to share about what's changed in the past year and the work for the next six+ months. The Road to 0.1 I had been noodling on the idea of a logic book since the pandemic. The first time I wrote about it on the newsletter was in 2021! Then I said that it would be done by June and would be "under 50 pages". The idea was to cover logic as a "soft skill" that helped you think about things like requirements and stuff. That version sucked. If you want to see how much it sucked, I put it up on Patreon. Then I slept on the next draft for three years. Then in 2024 a lot of business fell through and I had a lot of free time, so with the help of Saul Pwanson I rewrote the book. This time I emphasized breadth over depth, trying to cover a lot more techniques. I also decided to self-publish it instead of pitching it to a publisher. Not going the traditional route would mean I would be responsible for paying for editing, advertising, graphic design etc, but I hoped that would be compensated by much higher royalties. It also meant I could release the book in early access and use early sales to fund further improvements. So I wrote up a draft in Sphinx, compiled it to LaTeX, and uploaded the PDF to leanpub. That was in June 2024. Since then I kept to a monthly cadence of updates, missing once in November (short-notice contract) and once last month (Systems Distributed). The book's now on v0.10. What's changed? A LOT v0.1 was very obviously an alpha, and I have made a lot of improvements since then. For one, the book no longer looks like a Sphinx manual. Compare! Also, the content is very, very different. v0.1 was 19,000 words, v.10 is 31,000.1 This comes from new chapters on TLA+, constraint/SMT solving, logic programming, and major expansions to the existing chapters. Originally, "Simplifying Conditionals" was 600 words. Six hundred words! It almost fit in two pages! The chapter is now 2600 words, now covering condition lifting, quantifier manipulation, helper predicates, and set optimizations. All the other chapters have either gotten similar facelifts or are scheduled to get facelifts. The last big change is the addition of book assets. Originally you had to manually copy over all of the code to try it out, which is a problem when there are samples in eight distinct languages! Now there are ready-to-go examples for each chapter, with instructions on how to set up each programming environment. This is also nice because it gives me breaks from writing to code instead. How did the book do? Leanpub's all-time visualizations are terrible, so I'll just give the summary: 1180 copies sold, $18,241 in royalties. That's a lot of money for something that isn't fully out yet! By comparison, Practical TLA+ has made me less than half of that, despite selling over 5x as many books. Self-publishing was the right choice! In that time I've paid about $400 for the book cover (worth it) and maybe $800 in Leanpub's advertising service (probably not worth it). Right now that doesn't come close to making back the time investment, but I think it can get there post-release. I believe there's a lot more potential customers via marketing. I think post-release 10k copies sold is within reach. Where is the book going? The main content work is rewrites: many of the chapters have not meaningfully changed since 1.0, so I am going through and rewriting them from scratch. So far four of the ten chapters have been rewritten. My (admittedly ambitious) goal is to rewrite three of them by the end of this month and another three by the end of next. I also want to do final passes on the rewritten chapters; as most of them have a few TODOs left lying around. (Also somehow in starting this newsletter and publishing it I realized that one of the chapters might be better split into two chapters, so there could well-be a tenth technique in v0.11 or v0.12!) After that, I will pass it to a copy editor while I work on improving the layout, making images, and indexing. I want to have something worthy of printing on a dead tree by 1.0. In terms of timelines, I am very roughly estimating something like this: Summer: final big changes and rewrites Early Autumn: graphic design and copy editing Late Autumn: proofing, figuring out printing stuff Winter: final ebook and initial print releases of 1.0. (If you know a service that helps get self-published books "past the finish line", I'd love to hear about it! Preferably something that works for a fee, not part of royalties.) This timeline may be disrupted by official client work, like a new TLA+ contract or a conference invitation. Needless to say, I am incredibly excited to complete this book and share the final version with you all. This is a book I wished for years ago, a book I wrote because nobody else would. It fills a critical gap in software educational material, and someday soon I'll be able to put a copy on my bookshelf. It's exhilarating and terrifying and above all, satisfying. It's also 150 pages vs 50 pages, but admittedly this is partially because I made the book smaller with a larger font. ↩
Translating user interface of SumatraPDF SumatraPDF is the best PDF/eBook/Comic Book viewer for Windows. It’s small, fast, full of features, free and open-source. It became popular enough that it made sense to translate the UI for non-English users. Currently we support 72 languages. This article describes how I designed and implemented a translation system in SumatraPDF, a native win32 C++ Windows application. Hard things about translating the UI There are 2 hard things about translating an application code for translation system (extracting strings to translate, translate strings from English to user’s language) translating them into many languages Extracting strings to translate from source code Currently there are 381 strings in SumatraPDF subject to translation. It’s important that the system requires the least amount of effort when adding new strings to translate. Every string that needs to be translated is marked in .cpp or .h file with one of two macros: _TRA("Rename") _TRN("Open") I have a script that extracts those strings from source files. Mine is written in Go but it could just as well be Python or JavaScript. It’s a simple regex job. _TR stands for “translation”. _TRA(s) expands into const char* trans::GetTranslation(const char* str) function which returns str translated to current UI language. We auto-detect language at startup based on Windows settings and allow the user to explicitly set UI language. For English we just return the original string. If a string to be translated is e.g. a part of const char* array[], we can’t use trans::GetTranslation(). For cases like that we have _TRN() which expands to English string. We have to write code to translate it at some point. Adding new strings is therefore as simple as wrapping them in _TRA() or _TRN() macros. Translating strings into many languages Now that we’ve extracted strings to be translated, we need to translate them into 72 languages. SumatraPDF is a free, open-source program. I don’t have a budget to hire translators. I don’t have a budget, period. The only option was to get help from SumatraPDF users. It was vital to make it very easy for users to send me translations. I didn’t want to ask them, for example, to download some translation software. Design and implementation of AppTranslator web app I couldn’t find a really simple software for crowd sourcing translations so I wrote my own: https://github.com/kjk/apptranslator You can see it in action: https://www.apptranslator.org/app/SumatraPDF I designed it to be generic but I don’t think anyone else is using it. AppTranslator is simple. Per https://tools.arslexis.io/wc/: 4k lines of Go server code 451 lines of html code a single dependency: bootstrap CSS framework (the project is old) It’s simple because I don’t want to spend a lot of time writing translation software. It’s just a side project in service of the goal of translating SumatraPDF. Login is exclusively via GitHub. It doesn’t even use a database. Like in Redis, changes are stored as a series of operations in an append-only log. We keep the whole state in memory and re-create it from the log at startup. Main operation is translate a string from English to language X represented as [kOpTranslation, english string, language, translation, user who provided translation]. When user provides a translation in the web UI, we send an API call to the server which appends the translation operation to the log. Simple and reliable. Because the code is written in Go, it’s very fast and memory efficient. When running it uses mere megabytes of RAM. It can comfortably run on the smallest 256 MB VPS server. I backup the log to S3 so if the server ever fails, I can re-install the program on a new server and re-download the translations from S3. I provide RSS feed for each language so that people who provide translations can monitor for new strings to be translated. Sending strings for translation and receiving translations So I have a web app for collecting translations and a script that extracts strings to be translated from source code. How do they connect? AppTranslator has an API for submitting the current set of strings to be translated in the simplest possible format: a line for each string (I ensure there are no newlines in the string itself by escaping them with \n) API is password protected because only I can submit the strings. The server compares the strings sent with the current set and records a difference in the log. It also sends a response with translations. Again the simplest possible format: AppTranslator: SumatraPDF 651b739d7fa110911f25563c933f42b1d37590f8 :%s annotation. Ctrl+click to edit. am:%s մեկնաբանություն: Ctrl+քլիք՝ խմբագրելու համար: ar:ملاحظة %s. اضغط Ctrl للتحرير. az:Qeyd %s. Düzəliş etmək üçün Ctrl+düyməyə basın. As you can see: a string to translate is on a line starting with : is followed by translations of that strings in the format: ${lang}: ${translation} An optimization: 651b739d7fa110911f25563c933f42b1d37590f8 is a hash of this response. If I submit this hash with my request and translations didn’t change on the server, the response is empty. Implementing C++ part of translation system So now I have a text file with translation downloaded from the server. How do I get a translation in my C++ code? As with everything in SumatraPDF, I try to do things in a simple and efficient way. The whole Translation.cpp is only 239 lines of code. The core of translation system is const char* trans::GetTranslation(const char* s); function. I embed the translations in exact the same format as received from AppTranslator in the executable as data file in resources. If the UI language is English, we do nothing. trans::GetTranslation() returns its argument. When we switch the language, we load the translations from resources and build an index: an array of English strings an array of corresponding translations Both arrays use my own StrVec class optimized for storing an array of strings. To find a translation we scan the first array to find an index of the string and return translation from the second array, at the same index. Linear scan seems like it would be slow but it isn’t. Resizing dialogs I have a few dialogs defined in SumatraPDF.rc file. The problem with dialogs is that position of UI elements is fixed. A translated string will almost certainly have a different size than the English string which will mess up fixed layout. Thankfully someone wrote DialogSizer that smartly resizes dialogs and solves this problem. The evolution of a solution No AppTranslator My initial implementation was simpler. I didn’t yet have AppTranslator so I stored the strings in a text file in repository in the same format as what I described above. People would download it, make changes using a text editor and send me the file via email which I would then checkin. It worked for a while but it became worse over time. More strings, more languages created more work for me to manually manage e-mail submissions. I decided to automate the process. Code generation My first implementation of C++ side used code generation instead of embedding the text file in resources. My Go script would generate C++ source code files with static const char* [] arrays. This worked well but I decided to improve it further by making the code use the text file with translations embedded in the app. The main motivation for the change was to open a possibility of downloading latest translations from the server to fix the problem of translations not being all ready when I build the release executable. I haven’t done that yet but it’s now easier to implement given that the format of strings embedded in the exe is the same as the one I can download from AppTranslator. Only utf-8 SumatraPDF started by using both WCHAR* Unicode strings and char* utf8 strings. For that reason the translation system had to support returning translation in both WCHAR* and char* version. Over time I refactored the code to use mostly utf8 and at some point I no longer needed to support WCHAR* version. That made the code even smaller and reduced memory usage. The experience I’m happy how things turned out. AppTranslator proved to be reliable and hassle free. It runs for many years now and collected 35440 string translations from users. I automated everything so that all I need to do is to periodically re-run the script that extracts strings from source code, uploads them to AppTranslator and downloads latest translations. One problem is that translations are not always ready in time for release so I make a release and then people start translating strings added since last release. I’ve considered downloading the latest translations from the server, in addition to embedding them in an executable at the time of building the app. Would I do the same today? While AppTranslator is reliable and doesn’t require on-going work, it would be better to not have to run a server at all. The world has changed since I started SumatraPDF. Namely: people are comfortable using GitHub and you can edit files directly in GitHub UI. It’s not a great experience but it works. One option would be to generate a translation text file for each language, in this format: :first untranslated string :second untranslated string :first translated string translation of first string :second translated string translation of second string Untranslated strings are listed at the top, to make it easier to find. A link would send a translator directly to edit this file in GitHub UI. When translator saves translations, it creates a PR for me to review and merge. The roads not taken But why did you re-invent everything? You should do X instead. All other X that I know about suck. Using per-language .rc resource files Traditional way of localizing / translating Window GUI apps is to store all strings and dialog definitions in an .rc file. Each language gets its own .rc file (or files) and the program picks the right resource based on a language. This doesn’t solve the 2 hard problems: having an easy way to add strings for translations having an easy way for users to provide translations XML horror show There was a dark time when the world was under the iron grip of XML fanaticism. Everything had to be an XML file even when it was the worst possible solution for the problem. XML doesn’t solve the 2 hard problems and a string storage format is an absolute nightmare for human editing. GNU gettext There’s a C library gettext that uses .po files. This is much saner solution than XML horror show. .po files are relatively simple text format. The code is already written. Warning: tooting my own horn. My format is better. It’s easier for people to edit, it’s easier to write code to parse it. This looks like many times more than 239 lines of code. Ok, gettext probably does a bit more than my code, but clearly nothing than I need. It also doesn’t solve the 2 hard problems. I would still have to write code to extract strings from source code and build a way to allow users to translate them easily.
