How I Sandbox my AI Agents

Posted on 2026-05-14 in Software • Tagged with ai , firejail , linux , security

I've been using Opencode as my AI coding agent. Very unlike me, I don't have a long list of reasons why I picked it among the many alternatives. I just wanted to get started with an agent system that checked my main requirements:

  • Must be fully open-source.
  • Popular, meaning it's …

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Self-hosted Tailscale, Part 2: Ad-blocking DNS

Posted on 2026-05-11 in Software • Tagged with dns , howto , linux , security , tailscale , vpn

In Part 1 I set up Headscale and had every tailnet client use Cloudflare DNS. That works, but it's leaving value on the table: every device that connects to my Tailscale gets whatever DNS servers I set, so I might as well run my own DNS server inside the private …


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Self-hosted Tailscale, Part 1: Headscale and clients

Posted on 2026-05-05 in Software • Tagged with howto , linux , security , tailscale , vpn

I had been hearing a lot of people raving about Tailscale as a solution for interconnecting devices, or in other words for creating your own mesh VPN. It does seem great on paper: easy to set up, fast and lightweight, based on an open protocol (WireGuard), works everywhere, solves the …


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Pre-establishing SSH master connections for Ansible, or using OnlyKey with Ansible without losing your mind

Posted on 2026-04-07 in Software • Tagged with ansible , automation , howto , linux , security

I use an OnlyKey as a hardware security device for a variety of purposes:

  • Common passwords are one keypress away, they get typed automatically.
  • As 2FA in my password manager (KeepassXC), by applying HMAC on the password.
  • SSH connections.
  • GPG encryption and signing.

OnlyKey

SSH connections are handled through the …


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Announcing Reflex, a Pelican theme

Posted on 2026-02-16 in Software • Tagged with free-software , pelican

I'm happy to announce the public availability of my Pelican theme: Reflex. It is published on PyPI, which should be the best way for most users to install it.

When I first started this blog I decided on Pelican because I had lots of experience with Python, so it would …


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Self-hosted Home, Part 1: Design and Planning

Posted on 2026-01-25 in Software • Tagged with free-software , linux , self-hosting

Those who have been paying attention to the blog know that I bought a house and have been planning its full renovation. As a computer nerd what excites me the most is the opportunity to implement my dream smart home, networking and home server.

I have a clear idea of …


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Periodic script to back up installed OS packages

Posted on 2025-12-08 in Software • Tagged with backup , fish , free-software , howto , linux , shell

A while ago I switched to yadm for managing my dotfiles. One of its features I have been enjoying is its bootstrap support. I have been adding idempotent setup operations

My latest addition is a script that creates backup files with all installed OS packages. In case of disaster if …


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Responsible education in computing

Posted on 2025-11-09 in Software • Tagged with education , free-software , linux

My oldest daughter is turning 7 soon, and I have promised her a gift: her first computer. I'm secretly hoping that she will develop an interest in computing similar to my own. Not because I want to reproduce my childhood in her (although, of course, I would like to share …


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Now with self-hosted comments

Posted on 2025-02-10 in Software • Tagged with blog , free-software , howto , linux , privacy , self-hosting

A few days ago I received an email from a reader and fellow blogger, to let me know that he was following my blog and also gave me a shout out about my New Year's resolution to write at least one article every month of 2025, and that I was …


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My homelab setup

Posted on 2023-12-29 in Software • Tagged with backup , caddy , debian , docker , free-software , homelab , linux , kodi , nextcloud , nginx , privacy , self-hosting

Welcome to my homelab!

If you don't know what a homelab is, it refers to running servers from your home. What is a server? It's basically a computer that is always on, connected to the network, often with no display or input. For a longer explanation take a look at …


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