Marius 
In this article I present two tools that help you with a Docker image diff or Docker image analysis: “dive” and the slim.ai Docker Desktop extension. I explain use cases for which you need these tools, and I show screen shots that illustrate their usage. Introduction Docker images (or more generally: OCI images) have become … Read more
In this article I compare the programming languages Go vs. Python. I highlight 3 similarities and 12 differences. This comparison is written for senior developers, but it is not exclusively limited to Python developers: everyone with a OOP-language background (like Java or C++) will benefit. I also provide tips regarding learning resources you should start … Read more
The Docker build cache avoids rebuilding those parts of a Docker image that were already built. Unfortunately, cache misses are hard to debug. In this article I explain three frequent yet unexpected reasons for cache misses, with solutions. One of them is that COPY or ADD statements are rebuilt, because files have changed. To diagnose … Read more
This article demonstrates how you can do infrastructure testing for Ansible roles and playbooks. I explain how the tools Vagrant and Molecule+Docker let you easily provision temporary VMs or Docker containers in which you can experimentally run your Ansible roles/playbooks, or even run unit testing in Continuous Integration. Introduction to infrastructure testing Ansible is a … Read more
This Ansible introduction explains what Ansible is and how it works. I explain the most important concepts and demonstrate them by example. I go into common pitfalls, such as installing Ansible, handling secrets, or getting reproducible projects. Ansible introduction Ansible is a CLI tool that provisions other machines. Here, provisioning refers to installing and configuring … Read more
In this article I discuss container-based development, where you not only run but also develop and debug software inside a locally-running Docker container. I explain the advantages and disadvantages of this approach, and look at VS Code’s development container feature, various features of IntelliJ-based IDEs, and how to implement an IDE-independent approach. Introduction to container-based … Read more
In this book recommendation, I review the book Designing Data-Intensive Applications by Martin Kleppmann, released in 2017. I also offer my 46 page summary of the book as free download. What are data-intensive applications? This book targets software engineers and architects interested in building distributed systems. In contrast to compute-intensive applications, where CPU cycles are the primary … Read more
Collaborative code editors let developers write code together in real time, just like Google Docs. This article compares Microsoft Live Share, Code with me, and CodeTogether. I clearly demonstrate the limitations and benefits of each tool, including how it integrates into existing IDEs, end-to-end encryption and pricing. I’ll conclude with recommendations for different use cases, … Read more
In this article I discuss three types of Kubernetes development tools that speed up your daily development and debugging tasks: tools like Tilt that speed up development iteration cycles, general approaches for remote debugging with a debugger, and tools like Inspektor Gadget that help you diagnose problems in production. Introduction The increasing complexity of Kubernetes … Read more
Cluster introspection tools help you better understand what is going on in your Kubernetes cluster, by presenting the workloads visually. In this article I present a taxonomy of available tools and briefly present the tools Lens, k9s, kubenav, Octant, Headlamp, Kubernetes dashboard, Skooner and Portainer. I conclude by giving general recommendations. Introduction A very common … Read more