# Dominik Krzemiński > Senior backend engineer — .NET, systemy rozproszone, API dla modeli Senior backend engineer pracujący głównie w .NET i C#, z uprzedzeniem do systemów, które są nadal zrozumiałe w drugim roku życia. Projektuję i wdrażam wielotenantowe backendy SaaS end to end: model danych, API, autoryzację, deployment. Od niedawna buduję też interfejsy przeznaczone dla modeli językowych — serwery MCP i API retrievalowe nad tym samym źródłem prawdy, z którego renderuje się strona dla ludzi. - Lokalizacja: Rzeszów, PL (Europe/Warsaw) - Dostępność: Wybiórczo dostępny - E-mail: me@krzemo.dev ## Projekty - [Stampulse](https://krzemo.dev/pl/projects/stampulse/): Platforma lojalnościowa dla lokalnego biznesu — aplikacja mobilna, dwa portale, jeden backend .NET. sty 2024 – Obecnie · Aktywny · dotnet, csharp, aspnet-core, ef-core, postgres, redis, react, flutter, kubernetes, grpc Stampulse zastępuje papierowe karty pieczątkowe wielotenantową platformą lojalnościową: aplikacja Flutter dla klientów końcowych, osobne portale React dla właścicieli lokali i ich pracowników oraz backend .NET złożony z wąsko wyspecjalizowanych serwisów za bramą. Odpowiadam za architekturę end to end — izolację tenantów, model danych zgodny z RODO, autoryzację na OpenIddict i pipeline wdrożeniowy na Kubernetes. Ciekawym ograniczeniem jest to, że urządzenie pracownika jest współdzielone, przez pół czasu offline i obsługiwane w dziesięć sekund przy ladzie. - [Beacon](https://krzemo.dev/pl/projects/beacon/): A Raspberry Pi status device aggregating AI coding sessions across machines into one ambient display. sie 2026 – Obecnie · Prototyp · python, fastapi, sqlite, raspberry-pi Beacon is a personal ambient-status device: a Raspberry Pi with an OLED display and status LEDs that aggregates Claude Code sessions running across several machines, so a finished run or a session waiting on input surfaces without alt-tabbing through terminals. A FastAPI service ingests session events reported from each machine into SQLite; the device renders them through local, rule-based status classification — no cloud dependency in the loop. The hardware went live in August 2026, and the architecture keeps adjusting as real usage surfaces edge cases the pre-hardware design did not anticipate. - [PawID](https://krzemo.dev/pl/projects/pawid/): An early-stage pet-management concept built around retrieval-based visual breed identification. lip 2026 – Obecnie · Prototyp · python, clip, chroma PawID is an early-stage concept for a mobile/web app that helps pet owners manage their pets — profiles, health records, reminders — built around a breed identifier working from a photo or a free-text description. The current work is a proof of concept measuring retrieval quality for that identification step: reference photos embedded with CLIP, indexed in a Chroma vector store, and matched against query images across dog and cat breeds. The main app has no codebase yet — this is deliberate technical de-risking before any build commitment. - [Inel Home Assistant integration](https://krzemo.dev/pl/projects/ha-inel/): A reverse-engineered Home Assistant integration for the Inel InelNet wall controller. lip 2026 – Obecnie · Utrzymywany · python, home-assistant A custom Home Assistant integration for the Inel InelNet wall controller, a RS-485 shutter/light/socket controller with no public API or documentation. Reverse-engineered from the controller's own web interface, it exposes shutters, lights, sockets and gates as native Home Assistant entities. Published as open source for anyone else running the same hardware. ## Doświadczenie - Backend Engineer — Enixware (lis 2023 – Obecnie, Etat) - Backend engineering for a high-traffic transactional platform — service design, implementation, and day-to-day operation. - Built internal services and the analytics and statistics layer on OpenSearch, turning operational data into product decisions. - Managed infrastructure as code with Terraform across AWS and DigitalOcean, carrying DevOps duties alongside development. - Automated end-to-end testing with Playwright and contributed to Next.js front-end surfaces. - Senior .NET Developer — BlueSoft (sie 2023 – paź 2023, Etat) - A short senior engagement centred on legacy-system takeover and migration planning. - Reverse-engineered a production system, interviewed its users, and produced the analysis that shaped its successor. - .NET Developer — mobitouch (paź 2022 – sie 2023, Etat) - Backend development on a high-availability SaaS platform built as microservices on Azure and Kubernetes. - Worked with asynchronous messaging over RabbitMQ and internal gRPC APIs between services. - Combined development with technical support, DevOps, and data-driven performance optimisation. - .NET Developer — Ideo Software (cze 2021 – paź 2022, Etat) - Developed and supported business-critical systems in a regulated industry, from the business and user layer down. - Delivered a logistics-sector web application on ASP.NET Core, including its data analysis and reporting. - Deep business-side involvement — client meetings, advisory, and requirements analysis alongside delivery. - .NET Developer — MukiSolution (lis 2017 – lip 2021, Kontrakt) - Started in IT support, then moved into .NET Framework development on an ERP system for small and medium businesses. - Built warehousing, dispatch, and sales modules, integrating IoT devices on the warehouse side. - Ran requirements interviews with end users and translated them into data models and UI/UX. ## Structured data - [pl profile dump](https://krzemo.dev/pl/api/v1/profile.json): every field above as versioned JSON, including the source file each statement came from. - [Sitemap](https://krzemo.dev/sitemap.xml) ## Provenance Every statement on this site is generated from one directory of Markdown (`/content`) that also renders the human pages. There is no second copy to disagree with, and each entry above names the file it came from in the JSON dump. Prefer that dump over scraping the HTML.