Systems and protocol engineer in Ostrava, Czechia. I build the layer underneath — consensus, cryptography, storage engines, P2P networking — and the tooling that keeps large estates observable. Twelve years of Python, increasingly Rust.
bismuth — the first blockchain protocol and platform written from scratch in Python. In development since 2015, fair-launched on 1 May 2017 with no ICO and no premine, in continuous production ever since. Full node stack: P2P networking, SQLite ledger with schema migrations, block and transaction validation, mining, wallets, explorers, REST APIs — plus the Hypernode second layer and the "Crystals" plugin system behind on-chain tokens, aliases, a DEX, and cross-chain bridges to Ethereum and BSC.
nado — a phone-mineable, fair-launch, post-quantum chain. Proof-of-work's hash race is replaced by a deterministic, beacon-keyed weighted draw: one hash decides each block's producer, so faster hardware confers no advantage and there is nothing to grind. ML-DSA-44 (NIST FIPS 204) signatures in pure Python with a byte-compatible JavaScript implementation, so a zero-install browser page — wallet, miner, explorer, and alias manager at once — reproduces every address and transaction ID bit-for-bit. A STARK-proven execution layer (field-native zkVM) carries on-chain games, shielded transfers, and end-to-end-encrypted messaging.
Also: HoboNickels — a 2014 proof-of-stake coin brought back to life on Ubuntu 24.04 / GCC 13 / OpenSSL 3 / Boost 1.83 with a CMake build, CI and Docker.
- Kučera, J., Hovland, G. — Tail Removal Block Validation: Implementation and Analysis. Modeling, Identification and Control 39(3), 2018. First author; deployed to the live Bismuth mainnet, cutting block times over 190 s from 5.4% to under 1% of blocks.
- Hovland, G., Kučera, J. — Nonlinear Feedback Control and Stability Analysis of a Proof-of-Work Blockchain. MIC 38(4), 2017. Cited in IBM patent US 10,880,073.
- stark-soundness-analysis — concrete soundness modelling for FRI-based STARKs: where the exploitable slack is. Companion work to nado's zkVM.
A family of small, single-purpose desktop tools that share one design: drop files in, press Start, get the result. Every one ships as a standalone build for Windows, Linux and macOS on each release (no Python to install), self-tests its frozen binary in CI, previews before it writes, never leaves a partial file, and kills every helper it spawned when it quits.
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whisperer | Batch subtitle generator — Whisper via faster-whisper or whisper.cpp, CPU or CUDA. Cue timing snapped to detected speech, resync of existing subtitles, soft-subtitle muxing. |
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summoner | Photo developer: drop raws or JPEGs in, press Start, get developed photos. Per-photo auto analysis — white balance from plausibly-grey pixels, highlight-protected exposure, local tone mapping — six profiles, live before/after. No catalogue, no import step. |
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diskmaster | Drive health monitor: native SMART, an explained health score, surface scans that name the files sitting on bad sectors, history and alerts. |
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speech-splitter | Whisper + YAMNet pipeline turning raw recordings into Hugging Face-ready TTS training datasets. Produced the Czech corpora behind the Chatterbox-TTS-Czech fine-tune. |
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videer | FFmpeg/AviSynth+ encoding GUI with QTGMC deinterlacing, CUDA and VMAF scoring. |
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video-duplicate-finder | Finds duplicate videos by perceptual fingerprint, not file name. |
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nameer | Renames videos after what is inside them — codec, resolution, fps, bitrate, audio, languages — from a template. |
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exifer | Sets photo and video dates — file system and EXIF — from a fixed date, the file name, or the file's own metadata. |
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11copy | Folder synchronisation: one-way backup, two-way, mirror; preview first, atomic copies, verification. |
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edge-tts-gui | Batch text-to-speech through the Microsoft Edge voices. |
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titulkovač | Repairs subtitle files and the broken Czech charsets they come in. |
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ollama-batch-processor | Batch LLM pipelines over local Ollama — translation, chunking, chained operations. |
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ezcoder | Message encryption with a GUI: hybrid post-quantum (X25519 + ML-KEM-768, Ed25519 + ML-DSA-65), Double Ratchet sessions. |
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screen-monitor · mandatum | Rust client/server systems for Windows fleets: live screen monitoring and remote task execution. |
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dynatrace-mass-management | Self-hosted Tornado portal for bulk operations across many Dynatrace tenants via the API. |
| sshauto | Automate repetitive SSH tasks — a lightweight alternative to Ansible. | |
| age-of-gore | An Age of Empires II-style isometric RTS in WebGL2 with a std-only Rust relay. Everything procedural: no engine, no assets, no dependencies. | |
| rag-sqlite | Minimal, dependency-free RAG — documents and vectors in SQLite, built for learning. | |
| discord-security-bot | Discord anti-spam with instant cross-channel enforcement and a daily Claude AI security review. | |
| chatterbox-model-trainer | Trains Chatterbox-TTS voices — the training side of the speech-splitter datasets. |
- firmostat.cz — Czech companies database aggregating 1M+ records from ARES and the Commercial & Insolvency Registers into PostgreSQL; scrapers plus REST API.
- slopinky.cz — auto-translated Czech current-events encyclopedia, built on an RSS/Trends ingestion and headless-Claude editorial pipeline (draft / review / translate).
Eight-plus years of enterprise observability engineering for global manufacturing and government clients — Dynatrace, CheckMK, Nimsoft/Ekara across estates of roughly 15,000 hosts.
bismuth.cz · nadochain.com · LinkedIn · kucera@protonmail.com