Foundational topics on DevOps engineering, containers (Docker), cloud native computing and architecture, workload orchestration (Kubernetes and Swarm), automation (GitHub Actions), and Agentic DevOps.
Starting with a slim/distroless container image is necessary today, but it isn't enough. You need daily automation to trigger rebuilds for dependencies and base image digest updates. “All that work to slim your image down and using secure base images means little for security if you’re not also auto-rebuilding it for every upstream change, including detecting upstream base image digest…
My terminal emulator and shell setup for macOS, Linux, and Windows. AKA "Ultimate Terminal Setup" for me. I've kept this updated since 2017 , and everything has improved in the shell game! Keyboard fans are better off today than ever before. New terminals and AI Agents in 2024-2026 Ghostty 👻 is great, made by the co-founder of HashiCorp , Mitchell Hashimoto. It's pretty popular for being a young…
Docker now has three major AI features. I'll explain what they are and how to use them together. I've been spending an increasing amount of time using Docker's various AI features lately. Here's the easy guide to each and how to get started: Note: these tools are changing fast, and I expect them to get better over time. This is written in May 2025, and if I come back to update it, I'll indicate…
Container registries are becoming the universal artifact storage. The OCI updated the Distribution (registry) and Image specifications to 1.1 in 2024 to support any file type. Here's the back story, details on the changes, and various tools that can take advantage of this registry enhancement. 👨‍💻 OCI Registries for Everything? Docker didn’t just invent the modern container; they also…
TL;DR: "Frontends" are an optional feature of Dockerfiles that lets the Docker team add new build features (via BuildKit) that are beyond the traditional 1.0 Dockerfile. Here's how it works and some of my favorite new features. Did you know the Dockerfile keeps getting new features in something known as Dockerfile frontends ? Have you seen this first line in a Dockerfile example? #…
A DevOps Engineer is a great job that often has you working as a combination of a developer, a systems operator, and an automation expert. Here are the details to determine if this is the job for you. Common DevOps job roles I’ve worked in many teams doing this job, and I’ve also helped thousands of students who are currently in this role or want to do this job. However, the title…
In this article, I’m focusing on areas that should help you immediately advance your DevOps knowledge. First, I’ll list and detail what DevOps is and isn’t. Then, I’ll go through my DevOps evaluation to help you assess how “DevOps-y” you and your team are. For many years, I’ve been helping teams adopt and implement DevOps principles. The word DevOps gets…
As a Docker Captain and a Udemy instructor to 300,000 Docker and Kubernetes students , the Kubernetes vs. Docker topic comes up a lot. Like me, the tech world is enamored with container tooling, of which Docker and Kubernetes are the two top brands. Versus isn’t the right question, though, because using these tools isn’t an either-or equation. Consider these definitions: Docker Engine…
Swarm is alive and well. Let's see how Docker Inc. has publicly stated continued support for Swarm and Kubernetes, and dispel some myths about the SwarmKit project. 2025: No. Swarm is not dead. This article was written early 2018. See my updated post that dovers 2018-2025, and the latest 2025 update . The rest of this article was written in 2018 Swarm, aka SwarmKit aka Swarm Mode , aka Swarm…
When using Docker for Windows , you're actually using a tiny (custom) LinuxKit Linux running in a special Hyper-V VM. There's so much cool stuff happening, you're meant to forget it's still running on a Linux kernel. Note this is about the default "Linux Containers" mode. It doesn't work for "Windows Containers" mode. This is just a container that will have access to the Linux VM so you can do…