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You fail to learn if you don't learn to fail

from seated.ro [alt+shift+b] in programming

If all your time is spent watching output tokens, where do your input tokens come from? Letting an agent rip on full auto is basically doom scrolling. Even worse if you're doom scrolling while the agent runs. We humans love frying our dopamine receptors. This feels great until you realize what you were offloading: the struggle. The part where you fail. Failure is the entire point. You don't make progress in the gym unless you take a set at least close to failure. The muscle only adapts when it's forced to. It is no different for the brain. Cognitive Atrophy It is very hard to admit to yourself that your skills have atrophied. It is even harder to admit this to other people. I will admit that over the past several months my brain has gotten smoother (and I wasn't even on Twitter much!). Recently, I had written an abstraction for my diff viewer (diffy), an element system with a macro that lets agents write html-like code in rust for native ui (they reason better with this). But it wasn't adopted everywhere in the repo yet, so when I asked for a new feature, the model decided to hand paint it straight to the viewport instead. Every behavior the element system gives you for free was just... missing. Text wasn't selectable. Hover highlights wouldn't go away. And since I wasn't looking closely, it iterated on the slop and produced more slop, more bugs. I just kept saying continue. I lost a whole day untangling it, and the funny part is that once I actually looked at what it had built, every bug was the same bug. When you hit a roadblock and your immediate reaction is to reach for something else (previously, this used to be other people, but now it is a language model) you are essentially skipping the part where you actually learn to solve the problem. It is funny how one of the best "learning tools" has turned out to be the number one cause (anecdotal. sue me) of the lack of learning! It's been a few months since I started writing this, and things have gotten more dire....
12th Jul 2026

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More from seated.ro

glimpses of the future

Glimpse v1.0 Glimpse can now build call graphs, showing you exactly how functions relate to each other in your codebase. Video # what does main call? glimpse code :main # what calls this function? (reverse call graph) glimpse code :process_request --callers # limit the depth glimpse code :build --depth 3 This works by parsing your code with tree-sitter, extracting function definitions and calls, then resolving those calls to their actual definitions. Precise mode Sometimes tree-sitter based resolution isn’t enough. Maybe you’re dealing with dynamic dispatch, generics, or just a language with particularly complex module resolution. For this, Glimpse can use LSPs to resolve definitions semantically. glimpse code :main --precise This spins up actual LSP servers and uses goto-definition / goto-implementation to resolve calls. It’s slower, but accurate. Glimpse will attempt to auto-install the LSP servers for you. Indexing Glimpse eagerly caches whatever it finds into an incremental index. But you can choose to pre-build the index ahead of time for instant queries. # build the index glimpse index build # with LSP for precise resolution glimpse index build --precise # check what you've got glimpse index status The index stores all the definitions, calls, and resolutions so subsequent queries are fast. Language support Glimpse now supports: Go, Rust, C, C++, Python, TypeScript, JavaScript, Zig, Java, Scala, Nix, Lua, Ruby, C#, Kotlin, Swift, and Haskell. Each language has custom tree-sitter queries for extracting definitions, calls, and imports. The grammars are downloaded and compiled automatically on first use. Try it # install cargo install glimpse # or with homebrew brew tap seatedro/glimpse && brew install glimpse # or with nix nix profile install github:seatedro/glimpse # then just glimpse code :main

1st Jan 2026 • 1 votes
Devlog 001

This is a general devlog covering what I’ve been up to over the past few months! Haskell Hakyll is a Haskell library for generating static websites (yes, you do not, in fact, need Next.js for your personal site). The previous iteration of my website was written with Go + templ, and it was not static. I wrote everything myself, and it was, quite frankly, a horror to maintain. The templ LSP actually hinders more than it helps, and since I did not statically generate the content, it was kind of slow for a personal website. I did not like it. I added some very minor CSS fixes and a theme toggle button for my friend’s new website ludwigabap.com, and I saw the light that is Hakyll. :kneel: So I nerd-sniped myself into rewriting my personal website in Hakyll so that it generates beautiful HTML at build time (it uses Tailwind, too). All the dynamic bits of the website, like my silly stats and coding time, are served from a single Rust Axum server binary on my Hetzner VM that serves other stuff too (Memegrep’s server, among other things). Nix-pill This segues into my next nerd-snipe, or rather, my favorite new pill: the Nix pill. My entire website is built with a single Nix flake, including the Hakyll build step, the Cargo build step, and generating the resulting Docker image. Although, to be honest, the learning curve is very steep and I simply do not have it in me to master this language anytime soon, I like the principles, and it seems to me the least bad build system out there. I do most of my work on a MacBook running a NixOS VM as well. (seatedro/dotnix on GitHub.) It’s so much nicer to have a real dev workflow versus whatever the fuck macOS is. Sorry, but Homebrew is not good software. Ember The reason I started programming was that I was playing a game called Midtown Madness as a wee lad and decided that one day I would build a cool game like that. So, after 15 years, I’ve decided to embark on a small adventure to build a cool physics simulation (and eventually a voxel) engine. It’s written entirely in Zig because I enjoy writing Zig and did not want to touch C++ (although there were times I thought about committing this sin). When Ember gets far enough, I might write separate devlogs, but with what’s written so far, there isn’t enough to justify one. I was knee-deep in the mines because I wanted extremely specific features like multi-viewport docking with ImGui, and the off-the-shelf Zig libraries did not want to ship that for some reason. So there were many adventures in getting this shit to compile neatly. Ember now uses SDL3 for windowing and has an abstract rendering API (rudimentary, but the backends are in place) with SDLRenderer3, OpenGL, and WGPU-native backends that can be neatly switched at comptime. I’m using a bunch of cool resources to learn more about how to do this because I’ve never really written any game-dev related code before. I just want to build some cool simulations, and I will get there no matter what. github / seatedro / ember Thanatos After 5 years, I have finally built a new personal computer. I will be running NixOS as my main operating system with Hyprland and Wayland. I will also have Windows installed on a separate drive mainly for video games, though I expect to use Linux more often. It’s so nice not having to worry about my 256 GB SSD getting filled up on my MacBook Air. :> Exa Also, I joined Exa last month to work on the back-end team, and it has been so fun! I am soaking up as much knowledge from my significantly smarter peers at a good pace. As per custom, I revisited @ludwigABAP’s post: On becoming competitive when joining a new company. (PS: it’s on a new website.) Fin Back to the code cave I go—going to extract the polymorphic.

13th Jul 2025 • 1 votes
rabbit hole learning

Look everything up Pretty much the best way to learn that I have found is to refrain from suprressing your innate curosity and let it go wild. Most of the time, you will encounter a term or concept that you do not know, instead of glancing at it briefly, go all in. Google it, read the wiki page, found someone’s blog post? Read it. Watch that youtube video (I only do this if it’s not 3 hours like your average Sphaerophoria stream). Dive head first into rabbit holes. I’ll outline an average day where I have two types of goals: - Concrete goals: Like finish implementing X feature in Y project - Loose goals: Learn about X or Y. I will include rough timestamps but they are pretty much meaningless because productivity levels vary immensely throughout the day. 9:00 AM Decided to learn about document parsing. Links: EPUB specification, I found out that EPUBs are just an archive with HTML, and nearly had a crisis. (Now I know.) Immediate questions: so I need to parse the EPUB, extract metadata, fetch the XML and parse that too. Eventually I would have to use a WebView to render the HTML/CSS on the screen to render the book. (Unfortunate.) Found out that in order to read the PDF spec, you need to pay like 350 swiss francs! Spend time perusing SwiftUI docs, and asking grok about how I can render things on the screen with Swift. Fiddle with XCode, marvel at how Swift gets pretty much everything right but uses func ... for declaring functions. It has Result<T, E> though, so forgiven. 11:00 AM Began reading Computer Systems: A Programmer’s Perspective (CSAPP) Studied numeric representations, created Anki cards for hexadecimal conversion 12:00 PM Rabbit holed into learning so much about UTF-8 Bookmarked to learn more about UTF-8 and UTF-16 and writing a parser for it later (ILY @zack_overflow) 1:00 PM Taking a break, lunch + watching a movie. 2:30 PM Read Jon Olick’s single file resize implementation in C++ as reference (ILY @gizmobly) to roll my own resize library for use in glyph Rabbit holed into learning more about Sinc filters and the Lanczos Kernel. 3:30 PM Shifted to working on memegrep(v2). This is where I already know the goals I want to accomplish before the day ends. I implemented a pub/sub flow to help with scale when users upload their private memes. Rough sketch in mind: user uploads meme(s) → server receives req → insert skeleton into db → queue upload → return 201 to user immediately → worker picks up task Spent the next 6 hours coding without even realizing 6 hours had passed (bliss) Ended up with multi-file upload, search, deployed a CLIP model, added all the scaffolding needed in the UI for this. 9:30 PM I posted something about pointers on twitter and ended up reading some history about the nomenclature just for fun. Links: pointers, handles are the better pointers Also saw something about reference counting being used in the libvips library earlier in the day, so decided to check out their implementation since i’ve only used it in rust quite often. reference counting, Rc and Arc 11:00 PM Was in bed and saw a post linking an amazing article by Valve on Source Engine Networking, so ended up being a nice and light read. At the end of the day I ended up with more questions, but I definitely had more answers than when I started! Here’s a DAG of my exploration for fun:

9th Mar 2025 • 1 votes
two weeks is all you need

two-weeks I built a website (twoweeksisallyouneed dot com) with just Claude 3.5 Sonnet, zero lines of code written by me. Why I did this So a couple weeks back I had a computer vision midterm and i was allowed a single page of notes. I decided to use Claude to generate a cheat sheet in LaTeX. It was crazy lol, I was able to cook up something usable in 15 mins. pic.twitter.com/0tvIsdv34d — ro/nin (@seatedro) October 24, 2024 Someone had asked me to make a similar cheatsheet for ML, but I thought why not get claude to make an entire website instead? Early days I didn’t really give claude any specific information except what I wanted to build. My plan was as follows: > build out the UI skeleton first > populate with some dummy data > set up a content pipeline > tie up the ui with the data > fix bugs Claude decided to use react (Shocking). With just a couple of chats I was able to get the retro/hacker/matrix style UI down. (It’s going to be hard for frontend engineers to keep up with AI at this rate) I spent some time building and adding secrets/easter eggs to the website which no one has found yet lmaoooo. If/when all the easter eggs are found, I will open source the repository. Good hunting until then bros. Frustrations Things got really annoying, really fast. As soon as I wanted to build some sort of content pipeline, everything went to shit. Claude, no matter how smart of an AI, is not human. It did not think ahead. If I was going to build out this website I would not have started with a barebones react/vite app. I would have probably gone for a full stack framework like sveltekit instead. Generating content for the website was/is a nightmare. LLMs hallucinate, this is known, but did you also know how incredibly frustrating it is to get them to follow instructions? There were multiple instances where Claude (with all the 40% of project context of javascript code) generated a TypeScript interface and proceeded to spit TypeScript code. This project has 0 TypeScript???? The new edit in place nonsense was getting on my nerves. Half the time the output artifact wouldn’t even change, and the other half it would mess up the changes. I have to mention “please use a new artifact” if I wanted any real usable code. I was enthusiastic about building something with just Claude the first few days, then I started getting weary, and then eventually I wanted to take a sabbatical from using AI. When the project context grows, (think like 20% or more), Claude seems to have a hard time using that information. Often times I found myself hitting send, and Claude would spit some nonsense, I would hit stop and paste any relevant code directly and then get some useful code. Context is probably the biggest annoyance I’ve had with LLMs. Random thoughts Perplexity (with claude 3.5) is great (to an extent) because it’s essentially a RAG search so I was able to get somewhat up to date content for the resources and references sections from it. I feel like I was able to ship something of decent quality for sure, but I lost a lot of brain cells during the process. Do not take away from the programmer the only thing he wishes to do, program. Proompting I didn’t particularly do anything unique to get the best out of my prompts/chats. I did do everything in a Project on claude dot ai though, which let me set Project Instructions like so: BE ENTHUSIASTIC. WE ARE GOING TO CHANGE THE WAY THE WORLD LEARNS WITH THIS WEBSITE🚀🚀🚀🚀 LLMs seem to be much more open to doing anything you ask if you gaslight them, so go ahead and do it. Here are some prompts that I used while building the website: PROMPT ------ This is AWESOME: * For the loading screen add some text that says "you can learn anything in two weeks" * The ascii text is also weird, it says erain? is that supposed to mean something? * Where did all my placeholder topics go? * MOAR scrt scan lines * The matrix rain needs to fall vertically and it should be subtle. On mouse move it should get a bit brighter (the char under the mouse) What else do you think you could add? Surprise me One time I asked Claude to add something and it started changing the existing UI????? PROMPT: ------ OKAY, we have a beautiful boot sequence now. let's flesh out the main content screen. First let's fix some bugs: * The animations restart everytime i move my mouse instead of continue organically * What i mean is, when i move my mouse over the windows or around the matrix rain, the matrix rain restarts and so do the typewriter effect on the window title Work on these * [REDACTED] Easter eggs: * Fun Features: * "Power saving mode" that dims everything except what you're reading ....[REDACTED] So many times I ended up editing the prompt and adding lines like this: PLEASE DON'T CHANGE THE EXISTING UI. IT LOOKS GOOD BRO. I’ll just add some random prompts here PROMPT ------ Broski, we need to make the UI responsive and shit. Lot of people are reporting issues with it on mobile and smaller screens PROMPT ------ what sort of content do u think we should add? i was thinking things like formulae, charts (for phd), code blocks (for eng), research papers, youtube video links, blog posts etc. Let's think out loud how we're gonna do this before we proceed PROMPT ------ `pasted_code.jsx` Here is my current dashboard. Here is some sample concept content i have: `pasted_data.json` I need you to render this beautifully in the dashboard. Make any and all changes needed. It needs to look beautiful. And anything else u feel would be good. List out the things you're adding before adding it okay? Concluding thoughts This was a good experiment, a success. If you have a clear vision for what you want your product to be, then AI can help you achieve that vision quite well! However, I don’t think I will be using AI for the foreseeable future. I feel like my learning is stagnating the more i use AI and I want to write my slop code with my own two hands. I might use avante.nvim to quickly write some duplicated code here and there but by god, I miss coding. Actual coding.

21st Nov 2024 • 1 votes

More in programming

My new digital home

It's time for a dev blogger's favorite topic: blogging about my new blogging setup. After migrating my blog from Hexo to Eleventy, building a photography website and creating a personal one-pager, it was time to find a new digital home for all my projects. If you notice any issue after the migration, please let me know. I redirect the RSS feed to the new domain, but you might want to update the feed URL in your reader. Motivation I've been maintaining three different websites under two different names: a mostly developer-oriented blog, a photography portfolio and a one-pager gluing everything together. When I started blogging about my sabbatical journey, I was thinking about making yet another page to create a clear separation. I've decided to do the opposite and merge all my websites into one instead. As I further reduce my dependency on social media and third-party services, it has become even more important to have my own space and practice POSSE. Every decision I've made was driven by two main goals: simplicity and personality. Setup I've stopped chasing the latest and greatest. I want to keep the setup as clean as possible, which means pulling fewer dependencies. Every package adds complexity and maintainability costs, so I've only added what was necessary — no more Gulp, Sass or Tailwind. Instead of taking one of my existing websites as a starting point, I created this project from scratch. I reused some of my previous code, but I didn't want to take over any technical debt (especially with the advancements in CSS). The foundation of this website hasn't changed: Eleventy (Build Awesome). It covers the fundamentals of a static site and offers a great level of customization. I've made my project more and less dependent on Eleventy at the same time: I replaced Gulp as my build pipeline with pure Eleventy processing. I replaced most shortcodes with Markdown alternatives (and markdown-it plugins), which are better supported by editors like Obsidian. I've also replaced the Nunjucks template engine with Liquid, which comes with a few trade-offs. The main reason was to avoid creating a new collection for every set of posts I render. With Liquid, you can apply array functions like filtering or sorting in the template itself: {% assign drafts = collections.all | where: "data.isDraft" | reverse %} {% for draft in drafts %} … {% endfor %} Another advantage is having date formatting included, so I don't need another library or custom code. You can even set a default date format, so you don't have to provide it each time. What I don't like is the verbosity of the template language, although I've gotten used to it by now. Nunjucks: {{ "/tags/" + tag + "/" }} {{ modified or created or date }} {% set perspectives = ["dev", "photography", "life"] %} Liquid: {{ "/tags/" | append: tag | append: "/" }} {{ modified | default: created | default: date }} {% assign perspectives = "dev, photography, life" | split: ", " %} After migrating my existing content, I've noticed the build taking way too long, both in the dev server and the production build. I've found out that the Eleventy template cache is turned off for Liquid by default. This was useful during development, but when updating actual content, it caused every template and partial to be constantly recalculated. After turning the cache on, this issue was resolved: eleventyConfig.setLiquidOptions({ cache: true }); Check the colophon for the full tech stack overview. Perspectives The main challenge was finding a way to separate and present my main personas. The Venn diagram intersection of people interested in software development, photography and my personal life is probably small. I could use tags, but they don't offer the level of personalization I was looking for. Most personal blogs separate the content by post type (blog post, note, photo), but this doesn't fit my use case. Instead, I've decided to structure my website around three perspectives, a term I have borrowed from the Eclipse IDE. Each perspective comes with its own avatar, tagline and bio. If someone is interested in everything I share (hi Mom!), they can still view all my posts. Design Since building my photography website, I've made many changes, but I never got around to share an update. The biggest change was the design, which I have used as a blueprint for the new website. I've decided to mimic a social timeline/feed, which most people are familiar with. At the same time, it should be clear that it's a personal website and not yet another walled garden. Typography is an important part of every design. The first step is to choose between a system font stack and a custom font, which comes with the usual performance vs. personality trade-offs. I've decided to go with a uniform look across all devices. I've settled on Source Sans 3 for copy text and Hack for code. Another big change was introducing a sidebar. I always felt like the empty horizontal space was "wasted" on a desktop device, but getting the sidebar UX right is challenging. I'm happy with the result, especially with the last two panels adding a personal touch to the design. Images I've made several changes to the handling of image files. To make them compatible with Markdown editors, I had to replace my custom picture shortcode. The official Eleventy image plugin is a popular choice, but it violates my simplicity goal and doesn't support everything I needed. I've decided to go with a plain Markdown image markup and a single image file (no format fallback or 2x version for retina displays). Additionally, I wrote a markdown-it plugin to turn the optional title parameter into a caption. As for the file format, both WebP and AVIF have excellent browser support. For each image, I select the format based on the quality and file size. For my photos, I'm using WebP for the timeline thumbnails and JPG for the full-size version. Theme picker There have been some recent discussions about dark mode toggles, and I considered going for a light/dark solution based on the user's OS preference. Driven by the personality goal, I knew I had to add at least one more theme, so a proper theme picker was necessary. Similar to navigation, people like to hide the theme selection on mobile devices behind a burger menu or a dropdown. I prefer the solution by Sarah L. Fossheim, where all available themes are displayed above the page footer. A friend was scrolling through my new website, and their first question was "Why is the theme picker in the footer?". This tells me the solution was a good idea — I don't think he would have noticed a typical theme button in the header. The implementation follows standard practices: Use the light or dark theme as default based on the user's OS or browser preference. Store a selected theme in the local storage and use it as the single source of truth. Prevent a flash of inaccurate color theme. Make the theme play nicely with bfcache. I might have slightly gone overboard with my third theme, but the nostalgia kept me adding more and more features. Enjoy going back to the 90s: Feeds As browser vendors decided to remove XSLT support, I didn't bother to style my feed. Instead, I've created a new web feeds page, listing all available feeds and a short explanation. I provide one feed for every perspective and one with all my posts combined. I once offered tag-based RSS feeds. This was useful for my sabbatical, but even there I had only a single subscriber. Now, all tag feeds redirect to their main perspective feed. I've also dropped the JSON feed, despite having at least 16 subscribers. Given that every web feed reader supports Atom feeds, I don't see the value of providing a JSON alternative. A JSON feed doesn't add much complexity, but handling different media types (post, photo) and properly escaping the content is one more thing to implement and maintain. Quality assurance I've put a lot of effort into my new digital home, and I want to make sure it stays in good shape. I've included several tools, most running automatically as part of the CI pipeline: eleventyDataSchema — lint Eleventy data values like titles or dates markdownlint — format/lint Markdown files Vale — lint content (grammar, writing style, formatting) Lychee — find broken links (internal and external) Evaluatory — check accessibility and validate HTML Oxlint — lint JavaScript files Eleventy linters are another option to analyze a template's output, but I haven't found a use case for it yet. Not everything can be automated, so I also did the following manually: Test with Chrome, Firefox and Safari Test with Polypane Test with Google Lighthouse Test with a screen reader Test with JavaScript disabled Test with CSS disabled Test at 200% zoom Test with a bigger browser font size Test with custom fonts disabled Test with delayed assets Performance It's difficult to compare the performance of two separate websites with that of a combined one. Some parts got worse, e.g. bigger font files and more CSS. At the same time, I've noticed that gzip compression was turned off for anything but HTML for a few years now (I must have missed it when upgrading nginx) 🙈. One improvement was to implement on-demand assets. For example, the lite-youtube-embed CSS and JavaScript is only loaded if a <lite-youtube> element is present on the page. As before, JavaScript is fully optional (except for interactive demos in individual posts). I've been using a mix of <noscript> and CSS to hide elements that require JS (like the theme picker). I don't like the user experience of pagination, so I avoided it for years. But now that I have almost 300 posts, I've decided to finally add it. I display 30 posts per page, with images further down still being lazy-loaded for better performance. I haven't applied pagination to tag pages, as that's more complex with Eleventy. Bits and pieces Here are some other noteworthy changes: I've removed post-specific social share images and use a single WebP Open Graph image instead. I've dropped JSON-LD. Open Graph and microformats are sufficient. "Naming is hard" is a common expression in software development, but it also applies to photograph titles. I've decided to use a counter as the title, e.g. #0100. Sometimes I do come up with a title that I love, like the Castle in the Sky, so I might mention it in the description. On a photo page, you can now open the previous/next photo using the left/right arrow keys (in addition to the existing navigation buttons). It's now possible to filter photos by date, gear, or location. Check the explore page for an overview. I've learned about and used some experimental CSS features (with progressive enhancement), like scroll-triggered animations or squircle corners. I've added an AI statement on my LLM usage. I finally have a proper about page. Cool URIs don't change, but it's inevitable when moving to a new domain. All my previous URLs are redirected, except for some assets that are no longer used. I will keep the old domain, so the redirects will continue to work for a foreseeable future. I've kept my previous Easter egg and added a few more. Have a happy hunt! 🕵️‍♂️ Inspiration I visited hundreds of personal websites looking for inspiration. Here are a few that I kept coming back to: Emma Goto. I love Emma's approach to presenting the variety of her interests, even though I went a different route. Brennan Kenneth Brown. This website has so much to offer. It's a great example of what the open web looks like. Rex Barrett. The sentence "Collecting hobbies is my hobby." hit home — so much that I had to steal borrow it for my short life bio. Conclusion This project was mostly about merging the content of two websites into one. I knew this would take a considerable amount of time, but I still greatly underestimated the effort. In the end, it was all about the journey, not the destination. I loved fine-tuning the design and tweaking little details that probably no one will ever notice. I still have many more ideas left in my backlog. How do you like my new digital home? If you have an opinion, let me know! Reply via email

2 hours ago • 1 votes
Industrial Growth

New electronica album by Warrington-Runcorn New Town Development Plan

3 hours ago • 1 votes
Verifying my web archives with Playwright

To protect against link rot and disappearing content, I save local copies of web pages I like into my web archive. Ideally, this archive is completely self-contained. I want a local copy of each page’s HTML and all the assets it depends on (CSS, images, scripts, and so on). I don’t want my archived pages fetching resources from the original website, which could disappear at any time. Initially, I was verifying self-containedness by hand. I’d open each saved page in a web browser, and check the browser dev tools. I’d check the Console tab for errors and failed requests, and watch the Network tab for requests going out to the internet. That approach was tedious and error-prone, and I wanted something better. I now automate the process using Playwright, a testing framework that allows you to control web browsers. I open each page using Playwright, and check if it’s making external requests. Detecting external requests in Playwright When you open a page in Playwright, you can subscribe to request events which tell you when the page issues a request. In this Python snippet, we start Playwright, start a WebKit browser, and open a new page. We tell the page to append external requests to a list, and then load example.com. We see that example.com makes two requests on page load: one for https://example.com, and one for a JavaScript file. from contextlib import closing from playwright.sync_api import sync_playwright with ( sync_playwright() as p, closing(p.webkit.launch()) as browser, closing(browser.new_page()) as page, ): requests = [] page.on("request", lambda msg: requests.append(msg)) page.goto("https://example.com") print("requests:", requests) # requests: [<Request url='https://example.com/' method='GET'>, # <Request url='https://example.com/s.js' method='GET'>] In a more complex scenario, we might use Playwright to interact with the page after loading – for example, clicking a button or filling in a form, and then we could see the requests triggered by each action. Once we have a list of requests made by the page, we can inspect the url property to check if any of them were fetching from an external website. I wrote a function is_external_request to carry out this check: from playwright.sync_api import Request import urllib.parse def is_external_request(req: Request, original_url: str) -> bool: """ Check if a request has a different origin than the original URL. A request is considered internal if: - it matches the original URL exactly - it has the same scheme, host, and port as the original URL - it uses a `blob:` scheme (for example, in-memory media representations) """ if req.url == original_url: return False # Compare the scheme/host of the request to that of the original URL. org_url = urllib.parse.urlsplit(original_url) req_url = urllib.parse.urlsplit(req.url) if org_url.scheme == req_url.scheme and org_url.netloc == req_url.netloc: return False # Ignore blob: URLs, which are in-memory representation of some data, # and not an external request. # # Playwright detects blob: URLs when loading media files; for example # using the <audio> or <video> tag. if req_url.scheme == "blob": return False # Fail open: if we can't decide if a request was internal or external, # assume it was external. return True assert_page_is_self_contained(ctx, url) I’ve wrapped these two steps in a function assert_page_is_self_contained(ctx, url), which is part of my chives utility library. The function takes a Playwright Browser (or BrowserContext) and a URL, then: Opens a new page in the browser Loads the URL in the page Checks what happened when the page completes loading It throws an exception if there are any: Uncaught page exceptions or errors Console warnings or errors Non-GET requests Requests targeting external resources The function tries to trigger important network requests that might be skipped on the initial page load. For example, it evaluates the body’s offsetHeight to force a synchronous reflow, which causes the browser to request any lazily loaded images or fonts that might otherwise be missed. Here’s an example which verifies a file example.html from the working directory: from chives.browser_fixtures import assert_page_is_self_contained, file_uri from contextlib import closing from playwright.sync_api import sync_playwright with ( sync_playwright() as p, closing(p.webkit.launch()) as browser, ): assert_page_is_self_contained(browser, url=file_uri("example.html")) I originally passed a Page as the first argument, but changing the function to take a Browser or BrowserContext lets it manage its own pages. It gets a fresh page for every verification, and closes it when it’s done. (The first time I ran this, I created a new page for every verification, and never closed them – my computer ground to a crawl as my script opened hundreds of browser tabs.) If you create a new context, you can emulate different browser settings, like location, locale, and window size. Here’s an example where we use contexts to test the same page in light/dark mode: with ( sync_playwright() as p, closing(p.webkit.launch()) as browser, ): with closing(browser.new_context(color_scheme="light")) as light_ctx: assert_page_is_self_contained(light_ctx, url=file_uri("example.html")) with closing(browser.new_context(color_scheme="dark")) as dark_ctx: assert_page_is_self_contained(dark_ctx, url=file_uri("example.html")) In my web archive, I check every page in light/dark mode, and at 1×/2× pixel densities. It takes at least a second to run each verification, so I cache the results. As I save new pages, they’re added to a verification queue, and I’m warned of any missing assets. Unsurprisingly, the first run flagged many missing fonts and images, which I added to my local archive. Every saved page now passes cleanly. Browser is best-effort, but may still miss things Even with automated testing, it’s difficult to guarantee a completely self-contained archive. Different instances of a browser might load different assets, and a single page load might miss different variations: Responsive images – web pages can offer different sizes of an image, and the browser chooses a specific size based on the current window dimensions Appearance settings – a browser might load different fonts or images depending on light/dark mode Interaction-dependent assets – a web page might have assets that are only required on hover or user action You can mitigate some of this by testing with multiple contexts or adding post-load interactions, but every step makes the process take longer. Fortunately, most of the pages I save are simple, blog-style pages where I’ve stripped out the JavaScript. For my specific use case, initial load verification is more than good enough. Other uses for this code There are other projects where it could be useful to intercept and audit the requests made by a web page: Verifying your Content Security Policy (CSP). The CSP header restricts what resources can be loaded by a web page, and you could check that your configuration has the correct effect. Auditing login screens. You could check that sensitive pages don’t load any external scripts, which mitigates the risk of credential theft via a compromised third-party. Testing analytics and tracking. You could script user flows, like a shopping cart checkout, and confirm that tracking events fire correctly. I don’t do much front-end web development, but Playwright has become a key tool in my toolbox. I read a lot about people using AI agents and MCPs to interact with websites, but I prefer Playwright. It’s more fiddly and requires explicit instructions, but it’s constrained, deterministic, and I never have to worry about it doing something unexpected. [If the formatting of this post looks odd in your feed reader, visit the original article]

4 hours ago • 1 votes
Print Sales, Costs, And Profit: 2026

It’s four years since I bought a printer. I thought I would provide an update on running costs, print sales, and profit. I’m happy to be completely transparent about all this as I know it can be difficult to figure this out if you are thinking of creating your own printing business. January 11th 2026, 11:30am All the photos here are work shot in the last twelve months. Year Four Investment? Nothing other than consumables this year. I did purchase a high-spec film scanner last year, detailed here, but don’t consider that as part of this. The scanner has paid for itself several times over, and it may become a factor in future years (see below). Income Income is made up of sales through a local gallery that I am part of, along with web sales: 5,940.- CHF - sales through the gallery 80.- CHF - sales through web shop = 6,020.- CHF total income Total income is down about 50% compared to 2025. Costs I had to purchase consumables (paper and ink), at a total of 957.- CHF. That cost is included in the total here under the “print consumables” category. January 11th 2026, 3:30pm Rental cost of space in the gallery was reduced due to having overpayments of rent and my loan to the gallery, from the previous year(s), paid back to me. -1,500.- CHF - rental cost of space in the gallery -957.- CHF - print consumables (paper, ink) -1,138.- CHF - framing/mounting/postage -1,135.- CHF - commission to the gallery -300.- CHF - web shop subscription 0.- CHF - stripe / paypal fees 0.- CHF - advertising (none this year) = -5,030.- CHF total costs Total costs are down by about 60% compared to 2025. Total Profit 6,020.- CHF total income -5,030.- CHF total costs = 990.- CHF total profit A Quiet Year? Actually an average year. The previous couple of years were outliers, due to large orders, so really I’m back to normal in terms of sales. The key factors in managing to generate a [small] profit this year were: 1) no longer having to pay back the loan used to finance the printer, and 2) reduced rental cost of space in the gallery due to a previous loan to it being repaid. Also having to spend almost 1,000.- CHF on ink this year ate into profit. This is probably a “once every three years” cost given the rate I print at. The principal cost is rental of space in the gallery - in a normal year this would be 3,000.- CHF. Essentially this means, given the material cost of printing and framing/mounting and commission to the gallery, I need to make about 5,500.- CHF of sales to break even. Solar Eclipse, August 12th 2026 That’s a grind. However I did receive two substantial orders at the end of October, which haven’t made it in to this year’s figures and should boost next year’s. Maybe even a good sign for the year to come? At least now the original investment loan is repaid, the printing costs cover themselves in most years. I may look at offering scanning services now that I have a high-spec film scanner, which could become a scan + print service. More thoughts about that next time.

18 hours ago • 1 votes
F1

George Russell driving down the main straight during FP2.

18 hours ago • 1 votes
📚 BoredReading

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