Sebastian De Deyne

The complexity that lives in the GUI

∙ #programming #frontend

RoyalSloth reviews the three most common patterns to model interconnected state in a user interface.

  • Connect the boxes: create the user avatar component and pass its instance to the inventory table component
  • Lift the state up: move the internal state of the user avatar component and the state of the inventory table into a separate box/class
  • Introduce a message bus: connect the inventory table and the user avatar component to the shared pipe that is used for distributing events in the application

Connect the boxes and lift the state up seem to be the most common choices for React apps; respectively prop drilling and context or single state trees (like Redux).

There’s no silver bullet to UI complexity, all methods have their caveats.

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∙ 1 min. read ∙ #programming

There are two bike stalls near my apartment. One is right in front of the door, the other around the corner. The one in front of the door is closest, so when I can, I store my bike there. However, most of the time that stall is full, and I need to go around the corner instead.

That’s fine. Until a next morning–when I’m still in a daze because I’m not a morning person–I take the walk around the corner, only to realise my bike was actually in front of the door. The day before was one of those lucky days I could store my bike in front of the door.

I quit using the front stall. The less choices I have to make, the more room I have for important things.

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Local-first software

∙ 1 min. read ∙ #performance #ux #theweb

Google went down today. Downtime at this scale doesn’t happen often, but when it rains, it pours. Google going down doesn’t only affect Google products, it also affect products connected to Google. App that require authentication with your Google account weren’t available, unless you were already logged in.

Coïncidentally, I came across a compelling article about local-first software. From a SaaS point of view, before the internet all we had local-first.

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Embed a web page with a web component and the shadow DOM

∙ 2 min. read ∙ #webcomponents #javascript #vanillajs

Today, my colleague Freek asked for help embedding the webview of an email campaign in an iframe. He needed it in an iframe because embedding the HTML directly caused layout issues because the website’s CSS clashed with it.

After setting up the iframe, we needed to find a way to dynamically resize it based on its contents to avoid double scrollbars on the page. While possible, it required some icky scripting.

I took a step back. The problem at hand was that the CSS needed to be scoped somehow. While iframes were the only solution for a long time, these days we have the shadow DOM.

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Going deep

∙ 1 min. read ∙ #everything #software #performance

I recently stumbled across an over 5 year old comment on Hacker News about performance.

Lots of people make the mistake of thinking there’s only two vectors you can go to improve performance, high or wide.

  • High - throw hardware at the problem, on a single machine
  • Wide - Add more machines

There’s a third direction you can go, I call it “going deep”. Today’s programs run on software stacks so high and so abstract that we’re just now getting around to redeveloping (again for like the 3rd or 4th time) software that performs about as well as software we had around in the 1990s and early 2000s

Going deep means stripping away this nonsense and getting down closer to the metal, using smart algorithms, planning and working through a problem and seeing if you can size the solution to running on one machine as-is.

The author talks about “high” and “wide” hardware changes, but this can apply to software too. It’s easier to throw a cache at a slow piece of code than going deep and fixing it.

No need to look far, Electron is built on this principle. We’re adding heavy runtimes to support multiple platforms instead of staying close to the metal, and we pay the price in performance.

In general, it’s easier to add than subtract.

Which leads me to Derek Siver’s thoughts on subtraction.

Life can be improved by adding, or by subtracting. The world pushes us to add, because that benefits them. But the secret is to focus on subtracting.

The adding mindset is deeply ingrained. It’s easy to think I need something else. It’s hard to look instead at what to remove.

Adding is often a short-term solution. This isn’t necessarily a bad thing: time and budget restrictions are real problems. Adding often accrues more debt than subtracting, that’s the price we pay. Adding doesn’t save time, it lends time.


∙ #design #images #libraries

Last week, Unsplash added “blurhashes” to their API. Blurhashes are 20-30 character strings that represent a blurred placeholder of an image.

Blurred image placeholders aren’t new, but I was completely stomped to see what kind of gradient maps are generated with only 30 characters.

In short, BlurHash takes an image, and gives you a short string (only 20-30 characters!) that represents the placeholder for this image. You do this on the backend of your service, and store the string along with the image. When you send data to your client, you send both the URL to the image, and the BlurHash string. Your client then takes the string, and decodes it into an image that it shows while the real image is loading over the network. The string is short enough that it comfortably fits into whatever data format you use. For instance, it can easily be added as a field in a JSON object.

Unsplash uses the BlurHash algorithm to generate the placeholders. BlurHash is not a library but an algorithm, and they have 5 first party implementations including TypeScript. There’s also a third party package for PHP.

The algorithm is very simple - less than two hundred lines of code - and can easily be ported to your platform of choice.

Read more about BlurHash on GitHub.