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Last week, Plaid announced laying off 20% of its workforce (260 people). Today I signed my termination agreement, which makes this week my last week as part of Plaid’s infrastructure team. Kelly Sikkema Moving forward While being laid off and having to leave a very talented team is never a happy moment, I have decided to use the time ahead of me as an opportunity to focus on personal growth and figure out were I want my career to go next. I will not be seeking new full-time employment immediately. First, I want to get back into actually building things by myself. My programming skills and technology knowledge has immensely increased since I left college. Since then, I have not had the time and energy to get into serious side projects. I intend to use the next few months to fix that, although I am not sure exactly what form my new projects will take. Second, I need some time to explore infrastructure tooling outside of kubernetes. I enjoy working with kubernetes, but I am also...
over a year ago

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More from Alice GG

Building a container orchestrator

Kubernetes is not exactly the most fun piece of technology around. Learning it isn’t easy, and learning the surrounding ecosystem is even harder. Even those who have managed to tame it are still afraid of getting paged by an ETCD cluster corruption, a Kubelet certificate expiration, or the DNS breaking down (and somehow, it’s always the DNS). Samuel Sianipar If you’re like me, the thought of making your own orchestrator has crossed your mind a few times. The result would, of course, be a magical piece of technology that is both simple to learn and wouldn’t break down every weekend. Sadly, the task seems daunting. Kubernetes is a multi-million lines of code project which has been worked on for more than a decade. The good thing is someone wrote a book that can serve as a good starting point to explore the idea of building our own container orchestrator. This book is named “Build an Orchestrator in Go”, written by Tim Boring, published by Manning. The tasks The basic unit of our container orchestrator is called a “task”. A task represents a single container. It contains configuration data, like the container’s name, image and exposed ports. Most importantly, it indicates the container state, and so acts as a state machine. The state of a task can be Pending, Scheduled, Running, Completed or Failed. Each task will need to interact with a container runtime, through a client. In the book, we use Docker (aka Moby). The client will get its configuration from the task and then proceed to pull the image, create the container and start it. When it is time to finish the task, it will stop the container and remove it. The workers Above the task, we have workers. Each machine in the cluster runs a worker. Workers expose an API through which they receive commands. Those commands are added to a queue to be processed asynchronously. When the queue gets processed, the worker will start or stop tasks using the container client. In addition to exposing the ability to start and stop tasks, the worker must be able to list all the tasks running on it. This demands keeping a task database in the worker’s memory and updating it every time a task change’s state. The worker also needs to be able to provide information about its resources, like the available CPU and memory. The book suggests reading the /proc Linux file system using goprocinfo, but since I use a Mac, I used gopsutil. The manager On top of our cluster of workers, we have the manager. The manager also exposes an API, which allows us to start, stop, and list tasks on the cluster. Every time we want to create a new task, the manager will call a scheduler component. The scheduler has to list the workers that can accept more tasks, assign them a score by suitability and return the best one. When this is done, the manager will send the work to be done using the worker’s API. In the book, the author also suggests that the manager component should keep track of every tasks state by performing regular health checks. Health checks typically consist of querying an HTTP endpoint (i.e. /ready) and checking if it returns 200. In case a health check fails, the manager asks the worker to restart the task. I’m not sure if I agree with this idea. This could lead to the manager and worker having differing opinions about a task state. It will also cause scaling issues: the manager workload will have to grow linearly as we add tasks, and not just when we add workers. As far as I know, in Kubernetes, Kubelet (the equivalent of the worker here) is responsible for performing health checks. The CLI The last part of the project is to create a CLI to make sure our new orchestrator can be used without having to resort to firing up curl. The CLI needs to implement the following features: start a worker start a manager run a task in the cluster stop a task get the task status get the worker node status Using cobra makes this part fairly straightforward. It lets you create very modern feeling command-line apps, with properly formatted help commands and easy argument parsing. Once this is done, we almost have a fully functional orchestrator. We just need to add authentication. And maybe some kind of DaemonSet implementation would be nice. And a way to handle mounting volumes…

3 days ago 7 votes
Discord considered harmful

In the past few years, social media use has gained a bad reputation. More or less everyone is now aware that TikTok is ruining your attention span, and Twitter is radicalizing you into extreme ideologies. But, despite its enormous popularity amongst technology enthusiasts, there’s not a lot of attention given to Discord. I personally have been using Discord so much for so long that the majority of my social circle is made of people I met through the platform. I even spent two years of my life helping run the infrastructure behind the most popular Bot available on Discord. In this article, I will try to give my perspective on Discord, why I think it is harmful, and what can we do about it. appshunter.io A tale of two book clubs To explain my point of view about Discord, I will compare the experience between joining a real-life book-club, and one that communicates exclusively through Discord. This example is about books, but the same issues would apply if it was a community talking about investing, knitting, or collecting stamps. As Marshall McLuhan showed last century, examining media should be done independently of their content. In the first scenario, we have Bob. Bob enjoys reading books, which is generally a solitary hobby. To break this solitude, Bob decides to join a book club. This book club reunites twice a month in a library where they talk about a new book each time. In the second scenario, we have Alice. Alice also likes books. Alice also wants to meet fellow book lovers. Being a nerd, Alice decides to join a Discord server. This server does not have fixed meeting times. Most users simply use the text channels to talk about what they are reading anytime during the day. Crumbs of Belongingness In Bob’s book club, a session typically lasts an hour. First, the librarian takes some time to welcome everyone and introduce newcomers. After, that each club member talks about the book they were expected to read. They can talk about what they liked and disliked, how the book made them feel, and the chapters they found particularly noteworthy. Once each member had the time to talk about the book, they vote on the book they are going to read for the next date. After the session is concluded, some members move to the nearest coffeehouse to keep talking. During this session of one hour, Bob spent around one hour socializing. The need for belongingness that drove Bob to join this book club is fully met. On Alice’s side, the server is running 24/7. When she opens the app, even if there are sometimes more than 4000 members of her virtual book club online, most of the time, nobody is talking. If she was to spend an entire hour staring at the server she might witness a dozen or so messages. Those messages may be part of small conversations in which Alice can take part. Sadly, most of the time they will be simple uploads of memes, conversations about books she hasn’t read, or messages that do not convey enough meaning to start a conversation. In one hour of constant Discord use, Alice’s need for socializing has not been met. Susan Q Yin The shop is closed Even if Bob’s library is open every day, the book club is only open for a total of two hours a month. It is enough for Bob. Since the book club fulfills his need, he doesn’t want it to be around for longer. He has not even entertained the thought of joining a second book club, because too many meetings would be overwhelming. For Alice, Discord is always available. No matter if she is at home or away, it is always somewhere in her phone or taskbar. At any moment of the day, she might notice a red circle above the icon. It tells her there are unread messages on Discord. When she notices that, she instinctively stops her current task and opens the app to spend a few minutes checking her messages. Most of the time those messages do not lead to a meaningful conversation. Reading a few messages isn’t enough to meet her need for socialization. So, after having scrolled through the messages, she goes back to waiting for the next notification. Each time she interrupts her current task to check Discord, getting back into the flow can take several minutes or not happen at all. This can easily happen dozens of times a day and cost Alice hundreds of hours each month. Book hopping When Bob gets home, the club only requires him to read the next book. He may also choose to read two books at the same time, one for the book club and one from his personal backlog. But, if he were to keep his efforts to a strict minimum, he would still have things to talk about in the next session. Alice wants to be able to talk with other users about the books they are reading. So she starts reading the books that are trending and get mentionned often. The issue is, Discord’s conversation are instantaneous, and instantaneity compresses time. A book isn’t going to stay popular and relevant for two whole weeks, if it manages to be the thing people talk about for two whole days, it’s already great. Alice might try to purchase and read two to three books a week to keep up with the server rythm. Even if books are not terribly expensive, this can turn a 20 $/month hobby into a 200 $/month hobby. In addition to that, if reading a book takes Alice on average 10 hours, reading 3 books a week would be like adding a part-time job to her schedule. All this, while being constantly interrupted by the need to check if new conversations have been posted to the server. visnu deva Quitting Discord If you are in Alice’s situation, the solution is quite simple: use Discord less, ideally not at all. On my side, I’ve left every server that is not relevant to my current work. I blocked discord.com from the DNS of my coding computer (using NextDNS) and uninstalled the app from my phone. This makes the platform only usable as a direct messaging app, exclusively from my gaming device, which I cannot carry with me. I think many people realize the addictive nature of Discord, yet keep using the application all the time. One common objection to quitting the platform, is that there’s a need for an alternative: maybe we should go back to forums, or IRC, or use Matrix, etc… I don’t think any alternative internet chat platform can solve the problem. The real problem is that we want to be able to talk to people without leaving home, at any time, without any inconvenience. But what we should do is exactly that, leave home and join a real book club, one that is not open 24/7, and one where the members take the time to listen to each other. In the software community, we have also been convinced that every one of our projects needs to be on Discord. Every game needs a server, open-source projects offer support on Discord, and a bunch of AI startups even use it as their main user interface. I even made a server for Dice’n Goblins. I don’t think it’s really that useful. I’m not even sure it’s that convenient. Popular games are not popular because they have big servers, they have big servers because they are popular. Successful open-source projects often don’t even have a server.

2 weeks ago 13 votes
Thoughts on releasing our first indie game

Two weeks ago we released Dice’n Goblins, our first game on Steam. This project allowed me to discover and learn a lot of new things about game development and the industry. I will use this blog post to write down what I consider to be the most important lessons from the months spent working on this. The development started around 2 years ago when Daphnée started prototyping a dungeon crawler featuring a goblin protagonist. After a few iterations, the game combat started featuring dice, and then those dice could be used to make combos. In May 2024, the game was baptized Dice’n Goblins, and a Steam page was created featuring some early gameplay screenshots and footage. I joined the project full-time around this period. Almost one year later, after amassing more than 8000 wishlists, the game finally released on Steam on April 4th, 2025. It was received positively by the gaming press, with great reviews from PCGamer and LadiesGamers. It now sits at 92% positive reviews from players on Steam. Building RPGs isn’t easy As you can see from the above timeline, building this game took almost two years and two programmers. This is actually not that long if you consider that other indie RPGs have taken more than 6 years to come out. The main issue with the genre is that you need to create a believable world. In practice, this requires programming many different systems that will interact together to give the impression of a cohesive universe. Every time you add a new system, you need to think about how it will fit all the existing game features. For example, players typically expect an RPG to have a shop system. Of course, this means designing a shop non-player character (or building) and creating a UI that is displayed when you interact with it. But this also means thinking through a lot of other systems: combat needs to be changed to reward the player with gold, every item needs a price tag, chests should sometimes reward the player with gold, etc… Adding too many systems can quickly get into scope creep territory, and make the development exponentially longer. But you can only get away with removing so much until your game stops being an RPG. Making a game without a shop might be acceptable, but the experience still needs to have more features than “walking around and fighting monsters” to feel complete. RPGs are also, by definition, narrative experiences. While some games have managed to get away with procedurally generating 90% of the content, in general, you’ll need to get your hands dirty, write a story, and design a bunch of maps. Creating enough content for a game to fit 12h+ without having the player go through repetitive grind will by itself take a lot of time. Having said all that, I definitely wouldn’t do any other kind of games than RPGs, because this is what I enjoy playing. I don’t think I would be able to nail what makes other genres fun if I don’t play them enough to understand what separates the good from the mediocre. Marketing isn’t that complicated Everyone in the game dev community knows that there are way too many games releasing on Steam. To stand out amongst the 50+ games coming out every day, it’s important not only to have a finished product but also to plan a marketing campaign well in advance. For most people coming from a software engineering background, like me, this can feel extremely daunting. Our education and jobs do not prepare us well for this kind of task. In practice, it’s not that complicated. If your brain is able to provision a Kubernetes cluster, then you are most definitely capable of running a marketing campaign. Like anything else, it’s a skill that you can learn over time by practicing it, and iteratively improving your methods. During the 8 months following the Steam page release, we tried basically everything you can think of as a way to promote the game. Every time something was having a positive impact, we would do it more, and we quickly stopped things with low impact. The most important thing to keep in mind is your target audience. If you know who wants the game of games you’re making, it is very easy to find where they hang out and talk to them. This is however not an easy question to answer for every game. For a long while, we were not sure who would like Dice’n Goblins. Is it people who like Etrian Odyssey? Fans of Dicey Dungeons? Nostalgic players of Paper Mario? For us, the answer was mostly #1, with a bit of #3. Once we figured out what was our target audience, how to communicate with them, and most importantly, had a game that was visually appealing enough, marketing became very straightforward. This is why we really struggled to get our first 1000 wishlists, but getting the last 5000 was actually not that complicated. Publishers aren’t magic At some point, balancing the workload of actually building the game and figuring out how to market it felt too much for a two-person team. We therefore did what many indie studios do, and decided to work with a publisher. We worked with Rogue Duck Interactive, who previously published Dice & Fold, a fairly successful dice roguelike. Without getting too much into details, it didn’t work out as planned and we decided, by mutual agreement, to go back to self-publishing Dice’n Goblins. The issue simply came from the audience question mentioned earlier. Even though Dice & Fold and Dice’n Goblins share some similarities, they target a different audience, which requires a completely different approach to marketing. The lesson learned is that when picking a publisher, the most important thing you can do is to check that their current game catalog really matches the idea you have of your own game. If you’re building a fast-paced FPS, a publisher that only has experience with cozy simulation games will not be able to help you efficiently. In our situation, a publisher with experience in roguelikes and casual strategy games wasn’t a good fit for an RPG. In addition to that, I don’t think the idea of using a publisher to remove marketing toil and focus on making the game is that much of a good idea in the long term. While it definitely helps to remove the pressure from handling social media accounts and ad campaigns, new effort will be required in communicating and negotiating with the publishing team. In the end, the difference between the work saved and the work gained might not have been worth selling a chunk of your game. Conclusion After all this was said and done, one big question I haven’t answered is: would I do it again? The answer is definitely yes. Not only building this game was an extremely satisfying endeavor, but so much has been learned and built while doing it, it would be a shame not to go ahead and do a second one.

2 months ago 30 votes
Writing GDScript with Neovim

Neovim is by far my favorite text editor. The clutter-free interface and keyboard-only navigation are what keep me productive in my daily programming. In an earlier post, I explained how I configure it into a minimalist development environment. Today, I will show you how to use it with Godot and GDScript. Configure Godot First, we need to tell Godot to use nvim as a text editor instead of the built-in one. Open Godot, and head to Editor Settings > General > Text Editor > External. There, you will need to tick the box Use external editor, indicate your Neovim installation path, and use --server /tmp/godothost --remote-send "<C-\><C-N>:n {file}<CR>{line}G{col}|" as execution flags. While in the settings, head to Network > Language Server and note down the remote port Godot is using. By default, it should be 6005. We will need that value later. Connecting to Godot with vim-godot Neovim will be able to access Godot features by using a plugin called vim-godot. We will need to edit the nvim configuration file to install plugins and configure Neovim. On Mac and Linux, it is located at ~/.config/nvim/init.vim I use vim-plug to manage my plugins, so I can just add it to my configuration like this: call plug#begin('~/.vim/plugged') " ... Plug 'habamax/vim-godot' " ... call plug#end() Once the configuration file is modified and saved, use the :PlugInstall command to install it. You’ll also need to indicate Godot’s executable path. Add this line to your init.vim: let g:godot_executable = '/Applications/Godot.app/Contents/MacOS/Godot' For vim-godot to communicate with the Godot editor, it will need to listen to the /tmp/godothost file we configured in the editor previously. To do that, simply launch nvim with the flag --listen /tmp/godothost. To save you some precious keypress, I suggest creating a new alias in your bashrc/zshrc like this: alias gvim="nvim --listen /tmp/godothost" Getting autocompletion with coc.nvim Godot ships with a language server. It means the Godot editor can provide autocompletion, syntax highlighting, and advanced navigation to external editors like nvim. While Neovim now has built-in support for the language server protocol, I’ve used the plugin coc.nvim to obtain these functionalities for years and see no reason to change. You can also install it with vim-plug by adding the following line to your plugin list: Plug 'neoclide/coc.nvim', {'branch':'release'} Run :PlugInstall again to install it. You’ll need to indicate the Godot language server address and port using the command :CocConfig. It should open Coc’s configuration file, which is a JSON file normally located at ~/.config/nvim/coc-settings.json. In this file enter the following data, and make sure the port number matches the one located in your editor: { "languageserver": { "godot": { "host": "127.0.0.1", "filetypes": ["gdscript"], "port": 6005 } } } I recommend adding Coc’s example configuration to your init.vim file. You can find it on GitHub. It will provide you with a lot of useful shortcuts, such as using gd to go to a function definition and gr to list its references. Debugging using nvim-dap If you want to use the debugger from inside Neovim, you’ll need to install another plugin called nvim-dap. Add the following to your plugins list: Plug 'mfussenegger/nvim-dap' The plugin authors suggest configuring it using Lua, so let’s do that by adding the following in your init.vim: lua <<EOF local dap = require("dap") dap.adapters.godot = { type = "server", host = "127.0.0.1", port = 6006, } dap.configurations.gdscript = { { type = "godot", request = "launch", name = "Launch scene", project = "${workspaceFolder}", launch_scene = true, }, } vim.api.nvim_create_user_command("Breakpoint", "lua require'dap'.toggle_breakpoint()", {}) vim.api.nvim_create_user_command("Continue", "lua require'dap'.continue()", {}) vim.api.nvim_create_user_command("StepOver", "lua require'dap'.step_over()", {}) vim.api.nvim_create_user_command("StepInto", "lua require'dap'.step_into()", {}) vim.api.nvim_create_user_command("REPL", "lua require'dap'.repl.open()", {}) EOF This will connect to the language server (here on port 6005), and allow you to pilot the debugger using the following commands: :Breakpoint to create (or remove) a breakpoint :Continue to launch the game or run until the next breakpoint :StepOver to step over a line :StepInto to step inside a function definition :REPL to launch a REPL (useful if you want to examine values) Conclusion I hope you’ll have a great time developing Godot games with Neovim. If it helps you, you can check out my entire init.vim file on GitHub gist.

8 months ago 76 votes
Stuff I've been working on

It’s been around 2 years that I’ve had to stop with my long-term addiction to stable jobs. Quite a few people who read this blog are wondering what the hell exactly I’ve been doing since then so I’m going to update all of you on the various projects I’ve been working on. Meme credit: Fabian Stadler Mikochi Last year, I created Mikochi, a minimalist remote file browser written in Go and Preact. It has slowly been getting more and more users, and it’s now sitting at more than 200 GitHub stars and more than 6000 Docker pulls. I personally use it almost every day and it fits my use case perfectly. It is basically feature-complete so I don’t do too much development on it. I’ve actually been hoping users help me solve the few remaining GitHub issues. So far it happened twice, a good start I guess. Itako You may have seen a couple of posts on this blog regarding finance. It’s a subject I’ve been trying to learn more about for a while now. This led me to read some excellent books including Nassim Taleb’s Fooled by Randomness, Robert Shiller’s Irrational Exuberance, and Robert Carver’s Smart Portfolios. Those books have pushed me toward a more systematic approach to investing, and I’ve built Itako to help me with that. I’ve not talked about it on this blog so far, but it’s a SaaS software that gives clear data visualizations of a stock portfolio performance, volatility, and diversification. It’s currently in beta and usable for free. I’m quite happy that there are actually people using it and that it seems to work without any major issues. However, I think making it easier to use and adding a couple more features would be necessary to make it into a commercially viable product. I try to work on it when I find the time, but for the next couple of months, I have to prioritize the next project. Dice’n Goblins I play RPGs too much and now I’m even working on making them. This project was actually not started by me but by Daphnée Portheault. In the past, we worked on a couple of game jams and produced Cosmic Delusion and Duat. Now we’re trying to make a real commercial game called Dice’n Goblins. The game is about a Goblin who tries to escape from a dungeon that seems to grow endlessly. It’s inspired by classic dungeon crawlers like Etrian Odyssey and Lands of Lore. The twist is that you have to use dice to fight monsters. Equipping items you find in the dungeon gives you new dice and using skills allows you to change the dice values during combat (and make combos). We managed to obtain a decent amount of traction on this project and now it’s being published by Rogue Duck Interactive. The full game should come out in Q1 2025, for PC, Mac, and Linux. You can already play the demo (and wishlist the game) on Steam. If you’re really enthusiastic about it, don’t hesitate to join the Discord community. Technically it’s quite a big change for me to work on game dev since I can’t use that many of the reflexes I’ve built while working on infra subjects. But I’m getting more and more comfortable with using Godot and figuring out all the new game development related lingo. It’s also been an occasion to do a bit of work with non-code topics, like press relations. Japanese Something totally not relevant to tech. Since I’ve managed to reach a ‘goed genoeg’ level of Dutch, I’ve also started to learn more Japanese. I’ve almost reached the N4 level. (By almost I mean I’ve failed but it was close.) A screenshot from the Kanji Study Android App I’ve managed to learn all the hiraganas, katakanas, basic vocabulary, and grammar. So now all I’ve left to do is a huge amount of immersion and grind more kanjis. This is tougher than I thought it would be but I guess it’s fun that I can pretend to be studying while playing Dragon Quest XI in Japanese.

9 months ago 97 votes

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15 hours ago 3 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!

9 hours ago 2 votes
All about Svelte 5 snippets

Snippets are a useful addition to Svelte 5. I use them in my Svelte 5 projects like Edna. Snippet basics A snippet is a function that renders html based on its arguments. Here’s how to define and use a snippet: {#snippet hello(name)} <div>Hello {name}!</div> {/snippet} {@render hello("Andrew")} {@render hello("Amy")} You can re-use snippets by exporting them: <script module> export { hello }; </script> {@snippet hello(name)}<div>Hello {name}!</div>{/snippet} Snippets use cases Snippets for less nesting Deeply nested html is hard to read. You can use snippets to extract some parts to make the structure clearer. For example, you can transform: <div> <div class="flex justify-end mt-2"> <button onclick={onclose} class="mr-4 px-4 py-1 border border-black hover:bg-gray-100" >Cancel</button > <button onclick={() => emitRename()} disabled={!canRename} class="px-4 py-1 border border-black hover:bg-gray-50 disabled:text-gray-400 disabled:border-gray-400 disabled:bg-white default:bg-slate-700" >Rename</button > </div> into: {#snippet buttonCancel()} <button onclick={onclose} class="mr-4 px-4 py-1 border border-black hover:bg-gray-100" >Cancel</button > {/snippet} {#snippet buttonRename()}...{/snippet} To make this easier to read: <div> <div class="flex justify-end mt-2"> {@render buttonCancel()} {@render buttonRename()} </div> </div> snippets replace default <slot/> In Svelte 4, if you wanted place some HTML inside the component, you used <slot />. Let’s say you have Overlay.svelte component used like this: <Overlay> <MyDialog></MyDialog> </Overlay> In Svelte 4, you would use <slot /> to render children: <div class="overlay-wrapper"> <slot /> </div> <slot /> would be replaced with <MyDialog></MyDialog>. In Svelte 5 <MyDialog></MyDialog> is passed to Overlay.svelte as children property so you would change Overlay.svelte to: <script> let { children } = $props(); </script> <div class="overlay-wrapper"> {@render children()} </div> children property is created by Svelte compiler so you should avoid naming your own props children. snippets replace named slots A component can have a default slot for rendering children and additional named slots. In Svelte 5 instead of named slots you pass snippets as props. An example of Dialog.svelte: <script> let { title, children } = $props(); </script> <div class="dialog"> <div class="title"> {@render title()} </div> {@render children()} </div> And use: {#snippet title()} <div class="fancy-title">My fancy title</div> {/snippet} <Dialog title={title}> <div>Body of the dialog</div> </Dialog> passing snippets as implicit props You can pass title snippet prop implicitly: <Dialog> {#snippet title()} <div class="fancy-title">My fancy title</div> {/snippet} <div>Body of the dialog</div> </Dialog> Because {snippet title()} is a child or <Dialog>, we don’t have to pass it as explicit title={title} prop. The compiler does it for us. snippets to reduce repetition Here’s part of how I render https://tools.arslexis.io/ {#snippet row(name, url, desc)} <tr> <td class="text-left align-top" ><a class="font-semibold whitespace-nowrap" href={url}>{name}</a> </td> <td class="pl-4 align-top">{@html desc}</td> </tr> {/snippet} {@render row("unzip", "/unzip/", "unzip a file in the browser")} {@render row("wc", "/wc/", "like <tt>wc</tt>, but in the browser")} It saves me copy & paste of the same HTML and makes the structure more readable. snippets for recursive rendering Sometimes you need to render a recursive structure, like nested menus or file tree. In Svelte 4 you could use <svelte:self> but the downside of that is that you create multiple instances of the component. That means that the state is also split among multiple instances. That makes it harder to implement functionality that requires a global view of the structure, like keyboard navigation. With snippets you can render things recursively in a single instance of the component. I used it to implement nested context menus. snippets to customize rendering Let’s say you’re building a Menu component. Each menu item is a <div> with some non-trivial children. To allow the client of Menu customize how items are rendered, you could provide props for things like colors, padding etc. or you could allow ultimate flexibility by accepting an optional menuitem prop that is a snippet that renders the item. You can think of it as a headless UI i.e. you provide the necessary structure and difficult logic like keyboard navigation etc. and allow the client lots of control over how things are rendered. snippets for library of icons Before snippets every SVG Icon I used was a Svelte component. Many icons means many files. Now I have a single Icons.svelte file, like: <script module> export { IconMenu, IconSettings }; </script> {#snippet IconMenu(arg1, arg2, ...)} <svg>... icon svg</svg> {/snippet}} {#snippet IconSettings()} <svg>... icon svg</svg> {/snippet}}

yesterday 2 votes
Logical Quantifiers in Software

I realize that for all I've talked about Logic for Programmers in this newsletter, I never once explained basic logical quantifiers. They're both simple and incredibly useful, so let's do that this week! Sets and quantifiers A set is a collection of unordered, unique elements. {1, 2, 3, …} is a set, as are "every programming language", "every programming language's Wikipedia page", and "every function ever defined in any programming language's standard library". You can put whatever you want in a set, with some very specific limitations to avoid certain paradoxes.2 Once we have a set, we can ask "is something true for all elements of the set" and "is something true for at least one element of the set?" IE, is it true that every programming language has a set collection type in the core language? We would write it like this: # all of them all l in ProgrammingLanguages: HasSetType(l) # at least one some l in ProgrammingLanguages: HasSetType(l) This is the notation I use in the book because it's easy to read, type, and search for. Mathematicians historically had a few different formats; the one I grew up with was ∀x ∈ set: P(x) to mean all x in set, and ∃ to mean some. I use these when writing for just myself, but find them confusing to programmers when communicating. "All" and "some" are respectively referred to as "universal" and "existential" quantifiers. Some cool properties We can simplify expressions with quantifiers, in the same way that we can simplify !(x && y) to !x || !y. First of all, quantifiers are commutative with themselves. some x: some y: P(x,y) is the same as some y: some x: P(x, y). For this reason we can write some x, y: P(x,y) as shorthand. We can even do this when quantifying over different sets, writing some x, x' in X, y in Y instead of some x, x' in X: some y in Y. We can not do this with "alternating quantifiers": all p in Person: some m in Person: Mother(m, p) says that every person has a mother. some m in Person: all p in Person: Mother(m, p) says that someone is every person's mother. Second, existentials distribute over || while universals distribute over &&. "There is some url which returns a 403 or 404" is the same as "there is some url which returns a 403 or some url that returns a 404", and "all PRs pass the linter and the test suites" is the same as "all PRs pass the linter and all PRs pass the test suites". Finally, some and all are duals: some x: P(x) == !(all x: !P(x)), and vice-versa. Intuitively: if some file is malicious, it's not true that all files are benign. All these rules together mean we can manipulate quantifiers almost as easily as we can manipulate regular booleans, putting them in whatever form is easiest to use in programming. Speaking of which, how do we use this in in programming? How we use this in programming First of all, people clearly have a need for directly using quantifiers in code. If we have something of the form: for x in list: if P(x): return true return false That's just some x in list: P(x). And this is a prevalent pattern, as you can see by using GitHub code search. It finds over 500k examples of this pattern in Python alone! That can be simplified via using the language's built-in quantifiers: the Python would be any(P(x) for x in list). (Note this is not quantifying over sets but iterables. But the idea translates cleanly enough.) More generally, quantifiers are a key way we express higher-level properties of software. What does it mean for a list to be sorted in ascending order? That all i, j in 0..<len(l): if i < j then l[i] <= l[j]. When should a ratchet test fail? When some f in functions - exceptions: Uses(f, bad_function). Should the image classifier work upside down? all i in images: classify(i) == classify(rotate(i, 180)). These are the properties we verify with tests and types and MISU and whatnot;1 it helps to be able to make them explicit! One cool use case that'll be in the book's next version: database invariants are universal statements over the set of all records, like all a in accounts: a.balance > 0. That's enforceable with a CHECK constraint. But what about something like all i, i' in intervals: NoOverlap(i, i')? That isn't covered by CHECK, since it spans two rows. Quantifier duality to the rescue! The invariant is equivalent to !(some i, i' in intervals: Overlap(i, i')), so is preserved if the query SELECT COUNT(*) FROM intervals CROSS JOIN intervals … returns 0 rows. This means we can test it via a database trigger.3 There are a lot more use cases for quantifiers, but this is enough to introduce the ideas! Next week's the one year anniversary of the book entering early access, so I'll be writing a bit about that experience and how the book changed. It's crazy how crude v0.1 was compared to the current version. MISU ("make illegal states unrepresentable") means using data representations that rule out invalid values. For example, if you have a location -> Optional(item) lookup and want to make sure that each item is in exactly one location, consider instead changing the map to item -> location. This is a means of implementing the property all i in item, l, l' in location: if ItemIn(i, l) && l != l' then !ItemIn(i, l'). ↩ Specifically, a set can't be an element of itself, which rules out constructing things like "the set of all sets" or "the set of sets that don't contain themselves". ↩ Though note that when you're inserting or updating an interval, you already have that row's fields in the trigger's NEW keyword. So you can just query !(some i in intervals: Overlap(new, i')), which is more efficient. ↩

2 days ago 5 votes
The missing part of Espressif’s reset circuit

In the previous article, we peeked at the reset circuit of ESP-Prog with an oscilloscope, and reproduced it with basic components. We observed that it did not behave quite as expected. In this article, we’ll look into the missing pieces. An incomplete circuit For a hint, we’ll first look a bit more closely at the … Continue reading The missing part of Espressif’s reset circuit → The post The missing part of Espressif’s reset circuit appeared first on Quentin Santos.

2 days ago 3 votes