A Java geek

OpenTelemetry configuration gotchas

Last week, I described several approaches to OpenTelemetry on the JVM, their requirements, and their different results. This week, I want to highlight several gotchas found across stacks in the zero-code instrumentation. The promise of OpenTelemetry Since its inception, OpenTelemetry has unified the 3 pillars of observability. In the distributed tracing space, it replaced proprietary protocols Zipkin and Jaeger.

Technical

OpenTelemetry Tracing on the JVM

You may know I’m a big fan of OpenTelemetry. I recently finished developing a master class for the YOW! conference at the end of the year. During development, I noticed massive differences in configuration and results across programming languages. Even worse, differences exist across frameworks inside the same programming language.

Technical

Git default options

Git has become a fundamental part of our developers' daily routine that it’s hard to remember our lives without it. And yet, most of us use a limited set of commands and options. Today, I want to focus on two commands most developers probably use every day and look at the defaults behind them. git push After git commit, git push is probably the second most used command.

Development

Pattern-matching across different languages

Pattern matching is a major feature in software development. While pattern matching applies in several locations, its current usage is limited to switch case blocks. I want to compare the power of pattern matching across a couple of programming languages I’m familiar with in this post. I assume that every reader is familiar with the switch case syntax inherited from C.

Technical

Loosely coupled configuration for Home Assistant

This is the 8th post in the My journey with Home Assistant focus series. This post will be short, but I hope useful. My home is getting more and more connected, and the number of my automations grow each month. Recently, I equipped my roller shutters with connected Somfy engines so they could roll down automatically when it’s too hot in summer. Spoiler: given the current heatwave, it’s a boon!

Java

Do You know how to batch?

Concurrent systems face a delicate balance: enabling high throughput under contention while maintaining low latency and predictable behavior. Traditional locking strategies and naive parallelization often introduce performance bottlenecks through cache contention, false sharing, and excessive context switching.

Technical

Broadcast devices' name on the local network

With years, I accumulated devices on my local network, which in general run on Linux. I meticulously added them to my /etc/hosts/ file, so as not to remember their IP. Something puzzled me, though: my Synology NAS was readily available as nas.local on the network, without doing anything. I have close to zero skills in system administration, so here are my findings. The .local domain We can learn more about .local domain from Wikipedia. The domain name .

Development

Testing an OpenRewrite recipe

For the last two weeks, I’ve kicked the tires of OpenRewrite. At first, I created a recipe to move Kotlin source files as per the official recommendations with a set package name. I then improved the recipe to compute the root automatically. In both versions, I thoroughly tested the recipe. However, my testing approach was wrong. In this post, I want to describe my mistakes, and how I fixed them.

Development

Improving my previous OpenRewrite recipe

I started discovering OpenRewrite last week by writing a Kotlin recipe that moves Kotlin files according to the official directory structure recommendation. I mentioned some future works, and here they are. In this post, I want to describe how to compute the root package instead of letting the user set it.

Nicolas Fränkel's blog