Computers, the internet, apps, the online world — that's my thing.
What can I do?
- Golang – CDN services, Kubernetes operators, contributions to open source (ArgoCD, Kueue, Watermill).
- AI & coding agents – OpenCode, sandboxing & isolation of agents – network allowlists, rootless Docker, iptables – and integrating LLMs into developer workflows.
- media & streaming – VOD/LIVE transcoding (SW & HW), adaptive streaming (HLS/DASH), DRM, media containers & codecs, ffmpeg, MediaMTX, RTMP, SRT and SRTLA.
- Kubernetes – cluster design & operations, Helm, Kustomize, Jsonnet/Tanka, ArgoCD GitOps, custom Kubernetes operators, VPA/HPA tuning, DRA for HW transcoding accelerators.
- Python – my daily bread for 10+ years. Django, Flask, FastAPI, numpy, whatever's needed. Hammer, duct tape & WD-40 all in one.
- observability – OpenTelemetry stack, Prometheus, Grafana, Mimir, Tempo.
- infrastructure – OpenStack, NATS, Kafka, CI/CD (GitLab CI, GitHub Actions), Docker, Werf, Ansible.
- Linux – user and admin. Ubuntu, Debian, CentOS.
- web frontend – Vue.js with TypeScript, React. Tailwind for styling.
- databases – prefer PostgreSQL, but also MariaDB/MySQL; non-relational: Mongo and Redis.
- C/C++, Rust – not my primary languages, but I know my way around.
- what else? – LaTeX, VHDL, ASMx86, Qt TODO.
What I'm working on now
I have spent the past year mostly on coding agents – and specifically on how to let them loose on real code without it hurting. That means sandboxing, network isolation and a reproducible environment, not blind trust in the model.
jailoc Go, since March 2026
jailoc locks AI agents into a sandboxed Docker environment – a network allowlist enforced through iptables, a rootless Docker daemon resistant to tampering, an embedded Compose SDK, and zero-config startup. I lead development of this Seznam open-source project: we release regularly, it has documentation, and it is listed in awesome-opencode.
OpenCode and agent workflows
I use OpenCode daily, with my own skills built on top – plan protocol, systematic debugging, TDD, code review – and a set of rules for security, scope and git workflow. Agents run on this site too: it has its own AGENTS.md.
Background
Seznam.cz Senior Developer, since May 2023
In the CDN team of the Czech internet leader, I work on media processing services – storage, VOD & live encoding, content distribution infrastructure, and IPTV. Streamed storage, software & hardware encoding, hot-swapping input sources, all running on our own k8s clusters on top of OpenStack. Alongside that, I lead development of jailoc.
Previously (since September 2022) I started in the same team as a Python Developer.
Open Source
I actively contribute to upstream projects:
- ArgoCD – declarative continuous delivery for Kubernetes (22k+ stars)
- MediaMTX – live media server for SRT, RTMP, WebRTC and RTSP (20k+ stars)
- Kubernetes Kueue – Kubernetes-native job queueing (2.4k+ stars)
- Watermill – event-driven applications in Go (9.6k+ stars)
- Spegel – stateless cluster-local OCI registry mirror (3.5k+ stars)
- and more – NATS, OpenTelemetry, Knative Serving, Apache Airflow, werf, Tanka and jsonnet-libs
OLC Systems Fullstack Developer, 2014–2019
Long-term collaboration with an Olomouc-based company on information systems – sports, registry, manufacturing. Full-stack development on Django for clients like Czech Floorball, Mobilní pohotovost, and the Czech Equestrian Federation. Later integrating modern JS tools – Webpack and Vue.js.
Projects
Czech orienteering – livestreams 2023–…
For the Czech Orienteering Association I develop a web app for livestream graphics – real-time results, course maps, and data for TV broadcasts. Runs on live Czech orienteering events. Nuxt.js with Tailwind, Kubernetes.
Plus the broadcast infrastructure in Ansible – a MediaMTX stream proxy with native SRTLA for bonded mobile uplinks, Prometheus and Grafana.
Erasmus Festival 2022September 2022
A festival for five hundred international participants – two stages, three bands, DJs, Flag Parade through the centre of Brno. Promo, festival website, stage & light design, which I managed on-site from the lighting desk.
NA Brno dobrý April 2022
For the national ESN assembly I built the event website with programme, FAQ, and a map of key locations. Responsive design, Nuxt.js, Tailwind, data from Contentful.
ESN VUT Brno, ESN Riga2020–…
Member of the Erasmus Student Network – it started with volunteering at ESN Riga during my studies in Latvia. Then two years in ESN VUT Brno: directing livestreams during COVID, photo/video, and eventually the role of Events Manager – planning events for international students and leading organising teams.
IT work: standardisation under a GitHub organisation, process automation, development of Buena Fiesta – a social platform for matching international students with buddies.
Covid bez bariér April 2021
Web app covidbezbarier.cz for finding accessible COVID-19 testing & vaccination sites on a map. Nuxt.js, Tailwind, data from the Czech health registry, OSM map tiles. Featured by our university.
Litovel MINICUP 2013–2019
Information system for a mini-handball tournament – from results pages through scoring, photo tagging, to extended statistics.
From 2017 we added live broadcasts – first a mobile stream, then a custom iOS app for wireless video transmission, OBS and ffmpeg. In the final years: Blackmagic in FullHD, YouTube, Instagram, a live reporter and dozens of hours of live content with graphics and commentary.
Results management service (Django+Vue.js) distributed data to the web and livestreams – real-time clock, match status, rosters. Visual graphics by S. H. Nguyen in QML.
Education
Master's studies at University of Latvia 2019–2020
Two-semester Erasmus at the Faculty of Computing in Riga. Ten months of studying, exploring Latvia, volunteering for ESN Riga, and meeting students from around the world.
Bachelor's at FIT BUT in Brno 2016–2019
Applied Informatics – DNS resolver, compiler, network probes, model simulation. Bachelor's thesis: open platform for IoT node coordination in Node-RED with ESP32 firmware.
Technical High School, Olomouc 2012–2016
Electrical engineering → IT. Electrical certification comes in handy. First Linux install. Final project: an arena for battling bots programmed by other students.
Free time
I run – on roads and through forests with a compass and map. Orienteering combines physical challenge with terrain decision-making. I race recreationally and train regularly.
I take photos and document events – for fun and out of volunteering enthusiasm. Have a look at my not-too-diligently maintained portfolio.
I co-organise knight-themed camps for youth – continuing a 20+ year tradition of camps I attended myself.
TV series and films (mostly drama and sci-fi), rock of all kinds on Spotify, crypto.