Self-updating screenshots

(interblah.net)

414 points | by bjhess 1 day ago

37 comments

  • CyberShadow 15 hours ago
    Same, I've added a .#screenshots derivation. High up-front effort but almost zero maintenance afterwards.

    Bonus: since you're generating screenshots programmatically anyway, you can generate a pair of each with your app's light/dark theme, and swap them in/out depending on prefers-color-scheme: dark. <picture> elements work in GitHub READMEs, too: https://github.com/CyberShadow/CyDo#readme

    • 9dev 4 hours ago
      The <picture> in README trick works like magic. Thank you! I'm going to steal it.
    • neobrain 8 hours ago
      +1 for this approach. For a mobile app, I made Nix spawn an ephemeral Android emulator instance for generating up-to-date screenshots, requiring no prior setup and leaving no lingering data around after running. Setting it up wasn't that high-effort in my case either; coming up with the idea was the hard part, the Nix code was one-shot by your favorite LLM.

      Granted manually updating the screenshots isn't the most laborious task in the world, but the "upload-apk + take-screenshot + transfer-back-to-PC + edit" process is usually barely annoying enough that you end up almost never doing it otherwise (similar to the OP's experience in the closing paragraph).

  • Nashooo 9 hours ago
    Hey, you need to make your code examples horizontal scrollable on mobile! I could still guess their content based on context clues but still.
  • amiga386 6 hours ago
    If the author is reading this, please note your code blocks don't scroll (and in fact overflow the white text onto the white background) on mobile layouts. You need an "overflow-x: scroll" or such.
  • spuz 4 hours ago
    The only problem with this idea I can forsee is that the application and therefore the screenshots can change but the documentation does not. For example, if the documentation says press "Options > Customize" but the application is updated so this becomes "Preferences > Advanced" then the screenshot will show the new text but the documentation will still show the old labels. This would be very confusing as it would be hard to correlate what is being shown on the screenshot with the text. If the user saw the old screenshot they could more easily identify that they were looking at an out of date documentation.

    Having said that, have a process to automatically grab screenshots is going to make it significantly easier for a developer to update the docs so the motivation to keep the text up to date is going to be much higher.

    • zffr 23 minutes ago
      As a next step, it could be cool to write unit tests against these screenshots that look for words like you mentioned. That way if a screenshot is updated and a test breaks you will know what documentation to update
  • markaius 1 hour ago
    This reminds me of an small app I wrote and didn't do anything with-- You would choose an API / endpoint to grab data from, then choose how to display that text on a prebuilt or custom uploaded picture. On the ping it would rebuild the image and put the updated text from the api on it so you could have images with more current information (every 5/10/30 mins, etc.) Updating readmes with new screenshots on push is probably a much less cpu and better way to do dynamic image generation, for this use case.

    I never ended up using the idea the way I wanted, but this makes me think there's potential in this dynamic image domain yet!

  • furyofantares 15 hours ago
    Very cool.

    For the small casual games I've been vibe coding, I always start from a place where the application has a CLI where it can run headless, rendering to offscreen texture, with a a screenshot command as well as performance instrumentation. It takes no time to include all this, and gives the agent a way to automate the ui and inspect important things. It also lets me trivially have the agent update screenshots.

    Not as neat as being part of the build process, but I will now add that.

    • vidarh 4 hours ago
      I was toying with a DragonRuby game a while back, and did something like that. But DR also comes with recording reproducible playbacks, screenshotting etc. built in, couple hot reloading and easily being able to inject code into the running game, and it was great putting in place instructions so the agent could run the game fully and show off things for me in addition to allowing it to test things. I think we'll see more and more frameworks built to enable this - it's nice for human development, but it really pays off when you're working with an agent to have everything nicely runnable from a CLI and fully introspectible.
    • sho_hn 13 hours ago
      I do the same :-)

      I have an offscreen screenshot path, as well as a CLI arg for world pos/camera view vector, and scripted benchmark runs with a simple text-based input format that has rows of named segments of n game ticks length with control inputs per segment. Use that extensively for A/B testing of visuals and performance while working on the game code.

    • _fzslm 13 hours ago
      Would you mind sharing a link to some of these casual games? I ask cuz I'm also interested in how vibe coding can make game development easier.

      We had such a vibrant indie game scene when Adobe flash was about and since then nothing's really touched that level of ease of development. I think vibe coding is the first tool that actually exceeds it.

    • avaer 11 hours ago
      > It takes no time to include all this

      In some cases it does. Which engine?

      • furyofantares 2 hours ago
        I don't use an engine for vibing, they tend to be built around managing content and using their editors. You can drive engines from code but they are more built for invoking code from content usually. So I just use frameworks like SDL, Raylib C# and ebitengine. Most stuff I've done recently was ebitengine because I felt golang was the best thing to have LLMs writing when I started them.

        Right now I have my own framework which has a host written in Rust but game code is written in AssemblyScript - too early to tell how well this will work out but it is very promising to me right now.

        If I were just getting started I would probably pick some framework in Rust, or maybe Bevy which I believe is considered an engine but is code-centered.

  • merelysounds 13 hours ago
    This is very useful in mobile projects.

    App stores require screenshots, but generating N images for NUMBER_OF_SCREEN_SIZES times NUMBER_OF_LOCALIZATIONS can be a chore.

    In the past I wrote my own scripts for that, today tools like Fastlane[1] help.

    I use Fastlane for my logic puzzle game Nonoverse[2], you can see sample screenshots in its App Store page.

    I also automated App Preview video recording, complete with multiple scenes. If anyone wants to read more let me know, perhaps this is a good topic for an article.

    [1]: https://fastlane.tools/

    [2]: https://apps.apple.com/us/app/nonoverse-nonogram-puzzles/id6...

    • jdnebdbd 10 hours ago
      That sounds enticing! I can't figure out if it's a paid service or a local OS application though
      • merelysounds 9 hours ago
        Fastlane is a local, open source CLI tool.

        > 100% open source under the MIT license

        See: https://docs.fastlane.tools/

        It doesn’t support App Preview automation, this is something that I had to script myself.

  • martylamb 1 hour ago
    Very nice. I did something in a similar spirit eons ago for capturing CLI tool output directly into my docbook-based documentation. In my case it was also part of a build, generating intermediate .xml prior to running the docbook build.

    Ancient historical reference: https://martiansoftware.com/lab/rundoc

  • LeoDaVibeci 1 day ago
    I've needed this so many times. BTW this should be a meme: "I think this might be the neatest thing I’ve built in X that nobody will ever notice."
  • Mackser 8 hours ago
    Super cool! Love that you can declare the screenshots inline in the markdown document.

    For my desktop app I created a solution that generates screenshots in multiple languages, light/dark mode, removes noise and adds Windows/macOS window frames.

    Wrote about it here: https://maxschmitt.me/posts/cakedesk-website-redesign#screen...

    It's currently a separate script (which is a pain to maintain). I should look into making it a part of the markdown/mdx. Thanks for the inspiration!

  • schneems 14 hours ago
    This is neat. I wrote https://github.com/zombocom/rundoc. It has a similar feature. The main driver is to produce tutorials so it also puts the output of commands run back in the document.
  • infogulch 2 hours ago
    Can you do the same thing for websites with playwright/selenium?
  • amelius 4 hours ago
    Speaking of screenshots.

    Can we please agree that the OS should not send any event to applications while a screenshot is being made?

    It is very annoying if you press a screenshot button and suddenly menus disappear. Or much worse, the application sends a "screenshot taken" message back to the social media platform.

    • reddalo 3 hours ago
      I also can't stand Android preventing me from taking a screenshot. It's on my screen, I have the right to take a screenshot.

      I understand the technical limit of taking screenshots of DRM-protected content (e.g. Netflix), but why would my bank app be allowed to stop me from taking screenshots?

      • pwdisswordfishs 3 hours ago
        Solution: don't use mobile bank apps.
        • reddalo 1 hour ago
          I'm forced to use a bank app in order to authenticate, even if I want to login on the desktop website. I think it's because of an EU regulation for strong authentication.
      • Ylpertnodi 1 hour ago
        Ask them?
    • cbm-vic-20 4 hours ago
      The MacOS built-in screenshot tool has an optional "timed delay" feature, where you can click "screenshot in 5 seconds". With that time, you can open menus, or do anything that requires events to be processed by the application. Very handy for screenshots that require something to be clicked on.
      • amelius 4 hours ago
        I mean, I can probably do the same in X11 using xwd, with a sleep.

        But I just don't want my screenshot button to do anything else than taking a screenshot.

  • kalb_almas 13 hours ago
    I'm sometimes getting

    NoMethodError at /self-updating-screenshots undefined method `name' for nil:NilClass

    Ruby title-for: in handle, line 12 Web GET interblah.net/self-updating-screenshots

    followed by a very detailed traceback when I try to access the page

  • taspeotis 15 hours ago
    I’ve wondered about doing screenshots from the e2e test run, even keeping docs/ all together in the same repo so when you update the documentation and need a new screenshot you add a new test
  • cocoto 10 hours ago
    Wouldn’t a real live render approach work in this case? Have a live preview of your tool inside a rectangle. If the tool is light it should be optimal visually: it will respect browser rendering settings like accessibility parameters or custom addons.
  • maderalabs 14 hours ago
    Nice! I actually started to build this exact thing a couple years back, and ended up abstracting it out to something more generic with https://picshift.io/. That said, I still love the screenshot use case - the original name of this project was ScreenSync ;)
    • Barbing 12 hours ago
      Neat, good job, and good to have these different approaches out there
  • borplk 8 hours ago
    Site appears to be down intermittently with a Django error

    If author sees this: Turn off Django debug mode

  • efortis 1 day ago
    same here, but linking to the screenshots used for pixel diffing, which get committed to the repo.

    https://github.com/ericfortis/mockaton/tree/main/pixaton-tes...

  • Biganon 10 hours ago
    You should set DEBUG=False in your Django settings.
  • xp84 12 hours ago
    Bravo. This is incredibly useful, and really improves the quality of documentation, especially for many applications whose design and UI are always in flux.
  • bobek 12 hours ago
    Plus we had a visual diff on the top of that as a part of the CI pipeline. It prevented a bunch of mishaps ;)
  • willm 11 hours ago
    I approve of this approach.

    The docs for Textual (TUI library for Python) build screenshots along with the docs. Technically not really screenshots, they are SVGs, but principle is the same. They never get out of date.

    https://textual.textualize.io/widgets/markdown/#example

  • est 15 hours ago
    I maintain an internal wiki, the contents were generated by each CI/CD and always reflects from latest running code.
  • dhruv3006 11 hours ago
    This is very cool - I think I will try having this in https://voiden.md/.
    • Diti 7 hours ago
      “Crafted with care”, but the website has all the telltale signs of LLM slop.
  • boxed 9 hours ago
    For web projects, consider not doing screenshots at all and just embedding the html: https://kodare.net/2025/01/14/iframes-not-screenshots.html

    You can get responsive design in "screenshots" with this. Super nice, and people can copy paste, look at the code (useful for dev tools), etc.

  • 3eb7988a1663 15 hours ago
    shot-scraper is another project in this vein.

    https://github.com/simonw/shot-scraper

  • davidtio 9 hours ago
    Interesting app, definitely will reduce a lot of work updating documentation.
  • ekjhgkejhgk 6 hours ago
    > Your users might not notice, but you know, and it gnaws at you.

    The users WILL DEFINITELY notice if the screenshots don't match what they have in front of their eyes.

  • irishcoffee 14 hours ago
    I wrote a gui app once that ran on a safety-critical platform. I ended up stuffing a rendering of the gui (rendered offscreen) into shmem at I think 24hz, and rendered that screenshot into the safety critical application. I passed clicks (no typing for this gui) back from the statically rendered image updating on a cadence, to the offscreen GUI.

    Worked well. Not quite the same as this, but that’s what this reminds me of.

    • yjftsjthsd-h 13 hours ago
      I don't think I follow. What is that giving you that you wouldn't get by just having the user click in the application and see its real interface directly? Or are you saying you were embedding one application inside another?
      • jfim 13 hours ago
        My guess is that it's to ensure that the UI logic crashing or hanging doesn't bring down the safety critical process.
        • irishcoffee 5 hours ago
          The rendering of the safety-critical application was written completely in C using OpelGLSC (https://www.khronos.org/openglsc/) to render the GUI, and had to pass a formal validation suite (MISRA was the big one IIRC). Simply put, the safety critical application essentially was not allowed to "fail in an unsafe manner" in the DO-178 sense. Using javascript, or some c++ gui library was very much out of the question.

          Fortunately, this was not an airborne platform, so failing safely was much simpler than what a true aviation stack or medical stack would need to do.

  • npodbielski 7 hours ago
    I do not know why but looking at the title I was sure that this involves something like webserver that updates static file it serves by some external webhook.
  • immanuwell 1 day ago
    nice, embedding the capture instructions right in the markdown as comments is a dead-simple solution that'll age way better than any fancy external tooling
    • oneeyedpigeon 4 hours ago
      Except that it's brittle—HTML comments can be stripped. I wonder why they chose this approach vs. frontmatter.
  • sublinear 8 hours ago
    Why wouldn't you want to version the screenshots along with the text? That's a feature, not a bug.

    At best, this seems to require an unpublished draft state for all automatic screenshot updates until explicitly approved so that mistakes don't leak out to everyone else.

    At worst, this is an unrealistic level of discipline to keep things in sync that is far greater than just updating the docs normally with the next major version release.

    My alternative suggestion would be to make sure your test suite takes screenshots with every build. They're already perfectly organized and in the context of what you're documenting.

  • erikmay 11 hours ago
    Awesome! Now you could even go a step further and add satori to the pipeline to add content to the the fresh screenshot. This way annotation could be easily added to the screenshot.
  • devmor 12 hours ago
    Really love this, it should be standard practice!
  • TranspectiveDev 13 hours ago
    [dead]
  • Xmd5a 12 hours ago
    > Then you change the UI slightly – tweak a colour, move a button, update some copy – and suddenly every screenshot that includes that element is stale. You know they’re stale. Your users might not notice, but you know, and it gnaws at you.

    F

    Related: Sabotaging projects by overthinking, scope creep, and structural diffing – https://news.ycombinator.com/item?id=47890799

    • cluckindan 12 hours ago
      Read the article you’re linking to, it is not relevant here.
      • Xmd5a 6 hours ago
        Of course it is, he managed to avoid this pitfall, I "press F to pay respect"
        • spuz 4 hours ago
          "F" usually means somebody did something wrong and you are paying respect to their memory. You don't say it as a form of congratulations.
          • Xmd5a 3 hours ago
            > did something wrong

            Nah it's for those who sacrificed their own life, those who succumbed to the call of duty (or to the imperium of perfection) and put their teammates first.