Senior Full-Stack Web Developer · IoT Enthusiast · Local AI & Generative UI

Node.js-focused full-stack developer with 20+ years of experience building complex web applications. I love the frontend, I build things that run anywhere: from small computers to large-scale cloud-native setups. And I'm deep into local AI.

I'm exploring generative UI — interfaces that compose and adapt themselves around the task instead of a fixed set of screens. And I care about sovereign, on-prem AI: running models on your own hardware, keeping your data, your stack and your autonomy in your own hands.

📄 llms.txt — machine-readable profile for LLMs & ATS

• Frontend Engineering — performant, maintainable UI systems with HTML, CSS, JavaScript, TypeScript, Web Components and React
• Full-Stack & Node.js — APIs, microservices, system integration, Docker, CI/CD pipelines
• IoT & Edge Computing — Raspberry Pi, ESP32, MQTT, smart home, sensor & actuator setups
• Local AI — llama.cpp, Ollama, RAG, MCP — running big models on my own hardware

• Frontend engineering & UI architecture
• Full-stack development with Node.js
• API development & microservices
• System integration & interface engineering
• IoT & edge computing
• Smart home & sensorics
• Local AI & RAG
• Docker & containerization
• CI/CD & deployment automation
• Performance optimization
• Technical consulting & architecture
• Mentoring & team leadership (maybe)
• Client communication & project management (maybe)

mediamtx-ui Web-based admin dashboard for the MediaMTX streaming server — configuration, runtime, metrics, recordings and live logs.	gitea-qdrant-sync RAG + MCP + Web UI: semantic search over Markdown files in Gitea, powered by local LLMs (Ollama / llama.cpp) and Qdrant.
node-rtl433-ui Graphical web UI to map 433 MHz device values to MQTT topics, with a Node.js server acting as MQTT client.	spotify-kidsplayer Simplified Spotify UI for kids on a Raspberry Pi — text-to-speech, parent mode with PIN, local database.

• node-radio-automation — automatic radio stream generation per schedule; orchestration of multiple playlist audio streams with hot rotation, intros, spots and podcasts. github
• nodejs-tesseract-imagemagick-docker — Node.js app + Docker setup for OCR of bank statements (Tesseract + ImageMagick) into structured data. github
• nodemcu-lightdome — custom IoT device for 360° light measurement with four photo resistors, published on MQTT. github
• skwncr-kachelcast-panel — Grafana panel plugin (React) for weather forecast. github
• node-mqtt-transponder — MQTT transponder built with Node.js. github
• gamepad-browser-mqtt — reads a game controller in the browser and sends data to an MQTT broker. github
• bundesapi-jobsuche-client — web client for the German Federal Employment Agency job search API. github
• ffmpeg-rekorder — Raspberry Pi setup for an IP camera recorder. github
• drone-boat-dashboard / drone-boat-client — Open Research Buoy: real-time control via mobile network and WebSockets of a citizen-science buoy. github
• node-image-server-gallery — image gallery server with Node.js: image browser with on-demand thumbnail generation. github
• tech-radar-server — refactoring of Amazon's tech radar with Three.js. github
• skwncr — my own website: vanilla JavaScript meets Web Components. SSR/CSR frontend, data layer, server (SSR, thumbnails, PDF), all in one Docker image. github · skwncr.net

• Freelancer / Senior Frontend Engineer — 2023 → today · own projects, Web Components, local AI, own website & infrastructure
  • Built and maintain my own website infrastructure (SSR/CSR, data layer, Docker, nginx, CI/CD)
  • Developed a React plugin for Grafana 10 (Kachelcast weather panel)
  • Set up multi-arch Docker image publishing and deployment workflows
  • Developed microservices and web apps with Node.js
  • Realized frontend bundling for ESP32 devices
  • Deepened expertise in Web Components, vanilla JavaScript, TypeScript, React and Next.js
  • Worked on local AI projects (llama.cpp, Ollama, RAG, MCP)
• SYNERGY-NETWORKS GmbH — 2020 → 2022 · Shopware themes, Dockerized build pipelines, shop relaunch
  • Reorganized technical workflows company-wide and established Git usage
  • Set up multiple client shop projects with Docker for local development
  • Developed Shopware themes and extended frontend build pipelines (hot reloading)
  • Nearly solo shop relaunch (seiffen.com)
  • Docker dev environment (Mailhog, Redis, Elasticsearch, MySQL, phpMyAdmin)
  • Version and database migrations
• Neofonie GmbH / mobile.de — 2017 → 2020 · frontend modules for a major marketplace, cloud migration of (micro-)services
  • Developed frontend modules for mobile.de (e.g. 3D interior/exterior views)
  • Cloud migration of (micro-)services
  • Maintained and extended backoffice and B2B tools
  • Worked in international, cross-team teams with 15+ colleagues
• Freelance & agency work — 2008 → 2017 · corporate websites, build pipelines, frontend tooling
  • Valid Digitalagentur, familie redlich Systeme, Interactive Tools (liebherr.de), Unternehmenswelt.de, Construktiv GmbH (Mister Wong, Firefox plugin)
• XEBEC Mediafactory GmbH (co-founder) — 1999 → 2002 · online sales platform, corporate website, VRML production line
• TV & video production (self-employed) — 1991 → 1999 · 3D animation, broadcast engineering, live sports camera

• Digital Media (Studium Digitale Medien) — Hochschule für Künste (HfK) Bremen, 2003 → 2008 · design × IT crossover; courses at Uni Bremen (CS) and HfK Bremen (design)
• Fachabitur Gestaltung — Adolph-Kolping-Schule, Münster, 2002 → 2003

• Location: Britz (16230), near Eberswalde — about 60 km north of Berlin, easily reachable for on-site work
• skwncr.net
• LinkedIn
• matthias.kallenbach@skwncr.net
• YouTube

_{Built with ❤️, ☕ and a lot of local AI. Britz near Eberswalde, close to Berlin.}