2026
DNS as a Code: Managing Large DNS Zones in Git
Abstract: In this presentation, I will show you how we manage tens of DNS zones with several thousand records at the Faculty of Electrical Engineering (FEL) of the Czech Technical University (ČVUT) using the “DNS as a Code” and “GitOps” approaches.
We define DNS records in structured YAML files alongside organisational metadata, validation using JSON Schema, and a set of checks that catch logical errors across zones before deployment. Every change goes through a merge request and CI checks. The definitions are compiled into classic zone files for authoritative servers, and selected zones are generated from data in NetBox. A simple web application for convenient viewing and searching of records is also included.
Event: Installfest 2026
Slides on:
Electronic Door Signs at FEL CVUT
Abstract: At the Faculty of Electrical Engineering (FEL) of the Czech Technical University (ČVUT), we have started replacing paper classroom schedules with electronic paper. The new door signs display the daily timetable as well as what is currently taking place in the classroom. They are built on the open-hardware ESPink board from a well-known Czech manufacturer, feature a 10.2” e-ink display, a battery (or passive PoE), and a 3D-printed frame. We designed the firmware, the frame, the control software, and monitoring ourselves to suit our specific needs. The door signs communicate via Wi-Fi and MQTT – they receive images to display from the control server and send back telemetry data.
Event: Installfest 2026
Slides on:
2025
Electronic Door Signs at FEL CVUT
Abstract: At the Faculty of Electrical Engineering (FEL) of the Czech Technical University (ČVUT), we have started replacing paper classroom schedules with electronic paper. The new door signs display the daily timetable as well as what is currently taking place in the classroom. They are built on the open-hardware ESPink board from a well-known Czech manufacturer, feature a 10.2” e-ink display, a battery (or passive PoE), and a 3D-printed frame. We designed the firmware, the frame, the control software, and monitoring ourselves to suit our specific needs. The door signs communicate via Wi-Fi and MQTT – they receive images to display from the control server and send back telemetry data.
Event: OpenAlt 2025
Slides on:
2024
Automated macOS installation for VMs
Abstract: How to install macOS on a Linux virtualisation infrastructure – from downloading the installer from Apple, through installation, initial setup, customisation and creating a bootable disk image. And it’s done in a way that Cupertino probably hasn’t even thought of – without the use of a mouse, fully automated with CI. For comparison, I’ll also show how easy it is to do the same thing with Alpine Linux.
Event: Installfest 2024
Slides on: