Just uploaded the slides of my talk about Apache Lucene yesterday, along with a GitHub repo to check out the code samples.

Thanks a ton for the JUG Münster for having me and see you next time!

https://speakerdeck.com/spinscale/understanding-apache-lucene-more-than-just-full-text-search

Finished: Machine Learning - kurz & gut

A short (well, relatively) 300 pages, german reference guide about machine learning using python. If you know what you are searching for, this is a quick reference for ideas, but not so much for beginners.

I actually have no idea, how this ended up on my reading stack, but it's been there for some time so I figured to take a look.

Sunboard - A privacy-first, local-only dashboard for your PV/solar data

Finally had some time over the holidays to create a small Javelit app, that can be configured via the browser, downloads data from the open AlphaESS API, stores it in DuckDB, queries via JDBI and visualizes power consumption, grid pushing and how much money you saved over the years.

Used jreleaser to create releases for several platforms.

Check it out, happy for any feedback.

https://github.com/spinscale/sunboard

Finished: Latency

Dives into the various concepts/ideas of reducing delay in software. More geared towards junior/mid level engineers who haven't had to touch latency/performance topics yet and want to get familiar with, explaining a lot of concepts.

Around 240 pages, nice rust based code samples. For some points I wish there were more stories from experience and how latency was tackled in practice, as the book focused mostly on explanations.

Finally I am free of crutches again, but thanks to 3d printing I could at least have the crutches easy to reach for me after having a shower without having someone help me.

Being able to quickly measure the shower door, come up with a weight carrying design and then print a prototype to see if it fits correctly was so nice.

There's still more complex tasks like rounding edges easily, but we'll get there for the next task. Hoping no tools for post surgery equipment are involved.

Finished: Modern concurrency in Java

Nice 300 page introduction into Virtual Threads and Structured Concurrency, how those two work together. As I didn't have time to delve into Virtual Threads so far and even less into structured concurrency, this was a great refresher. Also comes with a nice introduction about reactive and where the current threaded model falls shorted, so nothing really missing.

Achievement unlocked: Added a cover slide using a terminal with figlet to my no-slides #elasticon presentation showing ES|QL to look into three years of solar data.

After the presentation quite a few folks came up to me and told me, why there was a certain PV produce during the time of year (less in July due to hot temperatures reducing production, thus higher in April). Thanks for all the pointers.

A part of the demo has also been written down in a blog post. See https://spinscale.de/posts/2025-10-07-solar-power-monitoring-with-elasticsearch-and-esql.html

dysk - A CLI utility to get information on filesystems, like df but better

A simple extension by adding better formatting via table and colors to a CLI tool, and to me it looks instantly a lot more useful than df. I wish existing tools would not be considered 'finished' sometimes, but extended, so you don't have to install and endless bunch of tools and aliases on a fresh system.

https://github.com/Canop/dysk

Finished: Optimizing Cloud Native Java

About 475 pages, but the name to me is a bit of misnomer. First mention of cloud seems after around 200 pages. A lot of great explanations around how the JVM works in general, performance testing, GC, but not really cloud specific to me. There's a small chapter at the end, but it's more about general k8s configuration and less about java specific tuning.

Good one to read for general overview and rather recent, but not cloud specific java tips and tricks.

Finished: A Philosophy of Software Design by John Ousterhout

Relatively short with a bit less than 200 pages, but I really enjoyed it. If you have been coding for long enough, so many things seem intuitive and factual in this book, but it's hard to put them into words, if you read your own code or others people's code to describe, what makes code better - better as in more readable, or easier to maintain.

Focusing more on practical things. A little light on testing, but I think that's ok.