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Ivan Velichko
@iximiuz
Software Engineer. Educator. Entrepreneur. Bootstrapping labs.iximiuz.com - a learning-by-doing platform to master Linux, Containers, and Kubernetes 🚀
Amsterdam
iximiuz.com
Joined May 2013
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    Ivan Velichko
    @iximiuz
    May 31
    How Servers Work: A Hands-On Introduction to TCP Sockets 🧙‍♂️ Hot off the press! Learn how servers actually work by building a tiny TCP server and client from scratch. Traditionally, with a bunch of visual explainers and practical challenges: labs.iximiuz.com/tutorials/how-…
    32K
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    Ivan Velichko
    @iximiuz
    Nov 22, 2022
    For years, I've been helping people master: - Containers - Kubernetes - Linux / Unix - Networking - Programming Tens of blog posts, hundreds of diagrams, and a bunch of OSS projects united by the above goal. If you haven't already, follow me today to speed up your learning!
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    Ivan Velichko
    @iximiuz
    Sep 22, 2025
    LeetCode, but for Linux, Docker, and Kubernetes? 🧐 Check out my collection of carefully crafted practical problems - with automated checks, helpful hints, and step-by-step solutions: labs.iximiuz.com/challenges A hands-on challenge a day keeps skill rot away.
    338K
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    Ivan Velichko
    @iximiuz
    Nov 1, 2022
    SSH Port Forwarding: Why and How 🧵 If these problems sound familiar: - A db server listens on a remote localhost, but you want to use a local GUI client - A dev service runs on your laptop, but you want to expose it to the Internet ...and you don't know the solution, read on!
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    Ivan Velichko
    @iximiuz
    Aug 28, 2022
    Debunking Container Myths 🧵 A (never-ending) series of articles that I started writing a couple of years ago to fix my own misconceptions about containers 🔽
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    Ivan Velichko
    @iximiuz
    Jun 16, 2024
    Gathered the main Docker concepts into one diagram 👇
    310K
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    Ivan Velichko
    @iximiuz
    Mar 26, 2025
    Docker 101: What happens when you run a container? 🧐 I've gotten a visual explanation of the "docker run" command and a very simple hands-on challenge. Give it a try if you've always wanted to get started with Docker: labs.iximiuz.com/challenges/doc…
    88K
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    Ivan Velichko
    @iximiuz
    Nov 3, 2022
    Computer Networking For Developers 🧵 Need to get into networking but all materials you find feel like they are written for bearded networking gurus? I've got a bunch of "different" articles for you! Written by a developer for fellow developers 👇
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    Ivan Velichko
    @iximiuz
    Aug 7, 2021
    How to grasp Containers and Docker (Mega Thread) When I started using containers back in 2015, I thought they were tiny virtual machines with a subsecond startup time. It was easy to follow tutorials from the Internet on how to put your Python or Node.js app into a container...
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    Ivan Velichko
    @iximiuz
    Nov 5, 2025
    Learn Linux, networking, containers, and Kubernetes by solving hands-on problems 🛠️ A curated collection of over 100 carefully crafted challenges - with interactive checks, clear diagrams, and helpful theoretical references. Like LeetCode but for DevOps labs.iximiuz.com/challenges
    70K
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    Ivan Velichko
    @iximiuz
    Oct 26, 2025
    SSH Tunnels: Port Forwarding on steroids Yesterday, we talked about Port Forwarding - an old networking trick that makes an endpoint accessible via a different address. Ports can be forwarded with socat & netcat, but there is a much more powerful and ubiquitous alternative: SSH.
    138K
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    Ivan Velichko
    @iximiuz
    Oct 27, 2025
    Computer Networking 101 (Mini-Course) 🧐 Why bother with learning about L2 broadcast domains if most of the day-to-day work happens ot L3 and above? Well, IP routing runs on top of Ethernet - computers can only send packets to their direct neighbours. When things go sideways
    79K
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    Ivan Velichko
    @iximiuz
    Dec 9, 2022
    Want to master Docker and become a container expert ...but don't know how to even start? 🔽 Here is the learning order that helped me: 1. Containers: how Linux does them 2. Images: why they are needed 3. Managers: many containers, one host 4. Orchestrators: many hosts, one app
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    Ivan Velichko
    @iximiuz
    Jun 20, 2024
    SSH Tunnels - A Visual Guide To Port Forwarding 🧵 One of my favorite parts of SSH is tunneling. With just the regular ssh client, you can do wonders! 1. Local Port forwarding Access private ports of a remote machine using local tools (your browser, a fancy DB UI client, etc)
    112K