Klaus Brunner’s personal website

GraalVM optimization levels matter (and the JVM is amazing)

Benchmarking some changes to my little solarpos command-line tool, I noticed something odd: the Homebrew-installed version (built with GraalVM native image using “optimise…

19 September 2025

Producing WebP images with R

For image files produced by R code for Web publication, the two most popular options are PNG and SVG (for raster and vector, respectively). There isn’t much of an…

Finding your Java code in GraalVM native images

I was curious what calls to Math.fma() would look like in GraalVM-generated native code on my Mac. Turns out it’s easy to check.

What I should probably tell students about generative AI

Everything has been said about GenAI already, but not yet by everyone. Here’s what I think students should hear.

ZIP: when good enough is good enough

For a little side project, I’ve recently had to dig into the details of the ubiquitous ZIP file format. That might sound boring, but it’s worth understanding that ZIPs are…

26 February 2025

Comparing Java libraries for sunrise/sunset calculation

How accurate are some of the available Java libraries to calculate sunrise and sunset times? This is not an exhaustive analysis; the idea is to get an estimate of what range…

24 February 2025