Linux

Almost nobody learns rm -rf the easy way. You read the man page, you use it carefully for a year, and then one day you watch your finger hit Enter a fraction of a second before your brain finishes checking the path. The commands that destroy data don’t punish typos. They punish the half second before the typo, when you were certain the path was right. That half second of doubt isn’t something documentation can give you. So I built a place where you can get it wrong on purpose, with nothing at stake but a score. ...

Every self-hosting guide starts the same way: “Forget Dropbox, forget Google Drive — run it yourself and save money.” I’m going to tell you something different. Self-hosting costs money. Self-hosting costs time. Self-hosting has hidden costs that nobody writes about until you’re three hours deep in a broken Docker volume at 11 PM on a Wednesday. This isn’t an anti-self-hosting post. I’ve been running my own servers at home for five years. I love it. But I wish someone had shown me this math before I started. So let me show you the math. ...

You don’t need to pay $10/month for Google Drive. Or $3/month for 1Password. Or $8/month for Notion. You can run all of this at home, on a single Raspberry Pi if you’re careful. But here’s the honest part: some of it is worth the effort. Some of it isn’t. I’ve run a self-hosted cloud at home for three years. This is what I’ve learned. ...

I wanted a personal AI assistant. Not a chatbot. Not a copilot. Something that actually does things — controls my desktop, reads my screen, talks to my smart home, answers questions in Finnish or English, and never, ever sends my data to a server I don’t control. The cloud options are good. They’re not mine. So I started building one. This post is the architecture document for that project. It’s a work in progress — the docker-compose is ready, the Ollama instance is running, and the first agent is next. I’m writing this because the design decisions are interesting, and because someone else might want to build the same thing. ...

Linux Things That Are Easy to Miss (Until They Bite You) The other day I spent 20 minutes debugging a cron job that worked perfectly when I ran it from the shell. The fix? PATH was different in cron. That’s not a one-time thing — I trip over the same class of subtle Linux papercuts every few months. So I wrote them all down. ...

In Part 1, we built a minimal Linux system using BusyBox and a prebuilt kernel. You got a shell running inside a container, mounted pseudo-filesystems, and saw the boot sequence from init to prompt. That was the “hello world” of custom Linux. Now we’re doing the real thing. Today we’re going to compile our own kernel from source, configure only the hardware support we actually need, and compress it to under 10MB. Then we’ll rip out that hand-written init script and replace it with systemd — the same init system that runs on virtually every modern Linux distribution. Finally, we’ll get a real service running (OpenSSH) so you can actually log into your custom system remotely. ...

If you’ve been administering Linux servers for a while, you’ve probably developed a love-hate relationship with it. You know how to configure services, debug networking issues, and keep systems running. But somewhere deep down, you’ve wondered: what actually holds this thing together? I don’t mean “how does systemd work” (nobody truly knows). I mean: what happens between hitting the power button and seeing a login prompt? Today, we’re going to build our own minimal Linux system from scratch. And because I’m not a sadist, we’ll test it using Docker containers - spin it up in seconds, tear it down just as fast. ...

Your OS Has Been Hiding Things From You (Windows & Linux Edition) Windows users think Linux is complicated. Linux users think Windows is a toy. Both are wrong. Both operating systems are packed with powerful features that most people — on either side — have never touched. This isn’t a “which is better” post. That argument is boring. This is about what your machine can actually do, regardless of which camp you’re in. ...