Because your threads are blocking my performance.

Image by Vesna Harni from Pixabay

Non-Blocking I/O has been around for a while. Different languages implement it differently, but all provide a way to reduce the thread count while seeming to allow full concurrency. …


How not to look like a noob.

Image by OpenClipart-Vectors from Pixabay

Reactive Java has been around for almost a decade now but I still see people that are struggling with it and, even worse, abusing it. So I thought I’d jot down the kinds of things I never want to see in a pull request.

1. Blocking

This should be obvious. It’s supposed…


Java microservices without Docker Desktop on macOS

Image by Pashminu Mansukhani from Pixabay

If you haven’t heard by now, Docker Desktop will charge a subscription fee for companies with more than 250 employees or more than 10 million dollars in revenue. It’s not a huge fee, and if your company is already using Docker Hub private repositories, I believe you’re covered. But it…


Moving away from thread-based context

Image by Jeon Sang-O from Pixabay

Microservices tend to do one thing and are dependent on other microservices for help in performing a complete transaction. As the action ping-pongs through the services, it helps to have a trace ID so you can tell who’s making the requests. …


Using Event Sourcing to implement CQRS

Image by Gerd Altmann from Pixabay

Command Query Responsibility Separation (CQRS) is a pattern in service architecture. It is a separation of concerns, that is, separation of services that write from services that read. Why would you want to separate read and write services? One of the advantages of microservices is the ability to scale services…


Staying cool, calm, and collected with a little preparation.

Photo by Hans Reniers on Unsplash

When I interview people I’m always optimistic that we’ll find the next great developer in our company. Unfortunately, it doesn’t often work out that way. People are rejected for a number of reasons, sometimes just because they don’t seem comfortable during the interview and that gives the impression that they…


TW: Death

Image by Axel Schäfer from Pixabay

I’ve been accused on more than one occasion of having a morbid sense of humor. I do. It’s probably one of my coping mechanisms for dealing with my anxious obsession with worst-case scenarios. …


A Java implementation for users and miners

Photo by James Kovin on Unsplash.

Cryptocurrency mining is probably a misnomer and results in some misunderstanding about what miners do. Mining usually evokes an image of extracting something, but with cryptocurrency mining, the miners are building the blockchain and getting paid to do it. …


Trust via peer-to-peer networking

Image by ClaudiaWollesen from Pixabay

In the first part of this series, we made a single blockchain. Now we’re going to make a set of them and get them talking to one another. The real point of the blockchain is a distributed system of verification. You can add blocks from any nodes and eventually it…


A simple explanation without the hype

Image by MichaelWuensch from Pixabay

Once again, cryptocurrencies are in the news everywhere. Are you still struggling with what cryptocurrencies are? Don’t worry, we all are. No one knows what to make of them or even how to value them. That’s why when you watch the crypto markets, you’ll get dizzy watching them go up…

Randal Kamradt Sr

Java software engineer for Coinme Inc. Artist and musician. https://rkamradt.github.io/

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