Patryk Śliż

Senior Full-Stack & AI Engineer

Summary

Full-stack developer with 8+ years of commercial experience (Angular, .NET Core, PostgreSQL), including nearly 4 years working fully remote in a ~10-person team. I build end-to-end: frontend, backend, and infrastructure - Docker, self-hosted CI/CD, networking. I work with applied AI in production: a Qdrant-based RAG with hybrid search, an MCP server, and a model routing gateway. Previously a Team Leader at two companies - code review, architectural decisions, onboarding and mentoring. Looking for a full-stack role, ideally one where AI is a real part of the product.

Experience

Full-stack DeveloperS&H Patryk Śliż

04.2023 - present

Own business - a startup project delivered in a team, alongside contract work. 2023: server infrastructure and CI/CD · 2024: feedback platform for SaaS applications and an e-commerce client · 2025: note-taking app with local-first RAG, agents and automation · 2026: production RAG and an MCP server

  • Startup project delivered in a team: full-stack (architecture, backend, frontend), infrastructure and deployments, plus running the project itself - sprint planning, backlog prioritisation and the release cycle. The product did not reach the market.
  • Long-term cooperation with an e-commerce client: a web application generating print-ready graphics files (Angular, .NET Core, PostgreSQL, SkiaSharp, Docker), deployed on the client's infrastructure with access over WireGuard.
  • Semantic model routing gateway: a custom layer selecting model and provider, with fallback once rate limits are hit - deliberately built without an off-the-shelf framework.

Full-stack Developer → Team LeaderLOG Systems sp. z o.o.

06.2019 - 04.2023

Wrocław, fully remote · ~10-person team · enterprise software: license management and asset monitoring · path: Full-stack Developer (06.2019) → Team Leader (10.2021)

  • Cut the full build and validation cycle from over an hour to a few minutes: dependency caching, replacing server drives with SSDs, removing steps that reached out to the internet on every run, and finally Yarn PnP. With a ~10-person team and many runs a day, that is tens of hours per week company-wide.
  • License management and company asset monitoring system: .NET Core, CQRS/MediatR, NHibernate, Angular, with PostgreSQL and MSSQL running in parallel.
  • Led a team of 3-5: sprints, estimates, code review, onboarding, mentoring, recruitment interviews, and taking on the hardest tasks.
  • Sole delivery of a workflow / onboarding system: Event-Sourced architecture on Marten and PostgreSQL, with modules communicating through events instead of REST. Solo full-stack - backend, frontend, architecture and deployment.
  • Refactored a legacy application onto a new architectural pattern while maintaining business continuity.
  • Owned entire modules of the system, including the whole authentication and authorisation layer - design, implementation and maintenance.

Frontend Team LeaderŻbik Sp. z o.o.

02.2018 - 07.2019

Rzeszów · MES systems for production floors · progression: Full-stack Developer (02.2018) → Frontend Developer (05.2018) → Frontend Team Leader (12.2018)

  • Led a 3-person frontend team: frontend architecture of the MES system, repository governance, sprint planning, coding standards and communication with the PM.
  • Refactored the entire frontend layer: five separate frontends replaced by one that launches modules depending on which backends are actually deployed on the application server.
  • Introduced a Git workflow standard (git-flow, release cycle) and a custom design system.

Projects

ClickUp Knowledge RAG + MCP serverarchitecture and implementation

Qdrant · nomic-embed · BM42 · MCP · PostgreSQL

  • RAG system over the ClickUp task base: API integration, local processing and indexing of content, exposed to language models through an MCP server.
  • Hybrid search chosen after my own evaluation - BM42 outperformed BM25 on this dataset.

Server and network infrastructure (small office)design and maintenance

Proxmox · Mikrotik · WireGuard · Gerrit · Jenkins · Docker

  • Network without a physical router - Mikrotik as a virtual machine handling routing, firewall and VPN for the entire host.
  • Multi-site VPN linking 4 locations over WireGuard tunnels, centrally managed.

Note-taking app with local-first RAGfull-stack project

SQLite / libSQL · Qdrant · local-first

  • Note-taking application with local-first RAG, handwriting support and a block editor.

Skills

AI / LLM
RAG, Qdrant, hybrid search (BM42, nomic-embed), semantic chunking, MCP, model routing, LLM agents, Claude Code (skills, hooks, MCP servers), self-hosted LLM (Ollama), n8n
Backend
.NET Core, C#, CQRS / MediatR, Event Sourcing (Marten), Entity Framework Core, NHibernate, Node.js, REST, JWT, xUnit, NUnit
Frontend
Angular, TypeScript (strict), RxJS, React, Tailwind CSS, Electron, Jasmine / Karma, Playwright (e2e), Storybook, Vite / esbuild
Databases
PostgreSQL, MSSQL, SQLite / libSQL, Qdrant, multi-tenancy
Infrastructure / DevOps
Docker (custom images), Proxmox, Jenkins, Gerrit, Linux, Mikrotik, WireGuard, Apache2, Cloudflare (Workers, D1), GitHub Actions
Engineering practices
unit and integration testing, code review and coding standards, git-flow and release cycle

Education

MSc in Computer Science, specialization: Artificial Intelligence · University of Information Technology and Management in Rzeszów

2026 - in progress

Part-time (evening and weekend) programme. Master's thesis: market situation analysis using machine learning - the model scores the impact of news narrative on price as a vector of relevance weights and uses it to adjust the signal from historical data and macroeconomic indicators.

Computer Science and Econometrics, Engineer's degree (inż., BEng equivalent) · Wyższa Szkoła Ekonomii i Informatyki w Krakowie (University of Economics and Computer Science, Kraków)

2016 - 2020

Part-time (evening and weekend) programme. Specialization: mobile and web application development.

Languages

Polish - native · English - B2 reading and writing, good listening comprehension, speaking in progress