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Showing posts from May, 2021

Messing around with kaboom.js

I created a simple "about me" website in the most ridiculous possible way I could imagine. I did it with kaboom.js , a simple library by  replit . It's best explained by just trying it out. Trust me, it is a fun way to spend an afternoon or two!

Fixing a laggy list

In an app I'm building, I use SVGs in certain list items. The SVGs are custom status icons and thus are pretty simple. They contain trivial path and circle elements, have one color without any fancy gradients. The list feels a bit janky though, especially on my crappiest Android test device. My intuition was already when I added the SVGs that this might happen. Android is not the most performant with vector graphics, especially when using react-native-svg. I did some profiling with the Flipper mobile app debugging tool. My gut feeling was confirmed. The component which is the most prominently visible in the flame graph is the SVG, being almost ten times slower to render than the text components.  Performance of the SVG component Since the SVGs are so simple, the solution to this performance problem is to convert the set to a font. We use a ton of icon fonts, and they are almost as fast to render as "normal" text. I used IcoMoon for the conversion. As expected, IcoMoon c

Seriously uncool Java?

A couple of podcasts I have listened to recently have flamed Java. It is a good "kusitolppa", a seriously uncool technology.  I'm pleased about not having to write Java anymore. Yet, I'll risk career suicide and take a stance to defend it against some of the low blows. After all, it was my bread and butter for quite many years. I get it; writing Java is not in fashion. It is likely a wrong choice for a modern startup. The language is full of mysterious cargo-cultish traditions, is verbose, has annotations on top of annotations and you have to use an editor which eats half of your memory (the other half is used by the Java process you are working on). Traditional Java and JDKs are ill-fitted for short-running processes like lambdas; it needs time to warm to get up to speed and needs more than one core to work efficiently. It has horrible dependency management tools by today's standards. Running a JVM process requires all kinds of weird flags, its defaults are unlik