About Me
A little more about my journey, interests, and the gear I use.
Who I Am
I'm Jakub Kuźnicki — a Computer Science engineer working on backend development and system architecture. Since June 2026 I've been a Junior Java Developer at Netcompany, building enterprise systems in Java and Spring Boot.
Before that, from March to June 2025, I interned as a Backend Developer at Paweł Weselak — Pragmatyczne Programowanie. I built LangChain document ingestion pipelines and RAG systems on LangChain4j and Spring Boot, and handled containerisation and deployment of LLM-driven processing.
Right now I'm moving toward DevOps and infrastructure. I run a bare-metal server at home and use it to get hands-on with networking and virtualisation.
# FAQ.sh
The questions that come up most, answered directly.
Who am I?
I'm Jakub Kuźnicki — brbn-jpg online — a Java backend developer in Warsaw, Poland, with an Engineer's degree in Computer Science. I've been a Junior Java Developer at Netcompany since June 2026, after a backend internship building LangChain ingestion pipelines and RAG systems.
What is my main technology stack?
Java and Spring Boot are the core, with PostgreSQL and Redis for data, Docker for packaging, and REST APIs as the default interface between services. For LLM work I use LangChain4j on the JVM and LangChain in Python. I also build frontends in Astro, React, Angular, and Vue when a project needs one, but backend is where I do my best work.
What RAG and LLM experience do I have?
It started with a backend internship at Paweł Weselak — Pragmatyczne Programowanie (March–June 2025), where I built LangChain ingestion pipelines and handled containerised deployment of LLM-driven extraction. I continued independently with LlamaTalks, a Spring Boot and LangChain4j chatbot that runs local models through Ollama, ingests documents into a vector store, and streams responses over SSE.
Where am I based, and do I work remotely?
Warsaw, Poland — I work out of Netcompany's Warsaw office. I'm comfortable with on-site, hybrid, and fully remote setups, and I work in Polish (native) and English (professional).
Am I open to new opportunities?
I'm employed at Netcompany and not actively job-hunting, but I read every message that comes in. If you have a backend or AI-engineering role involving Java, Spring Boot, or RAG, use the contact form on this site and I'll get back to you.
What is the largest project I have built?
todrawn.com, a live interactive whiteboard SaaS. It's built with Java 21 and Spring Boot on the backend, Next.js, React, and TypeScript on the frontend, and uses PostgreSQL, Redis, WebSockets, Stripe, Docker, and Google Cloud Run.
Why "brbn-jpg"?
They're the same person — me. I've used the handle brbn-jpg online for years, and it's the name of my GitHub account — the handle is on github.com/Brbn-jpg, the name is on my CV.
# My Interests
Tech & Hardware
I love building PCs and I'm passionate about hardware specifications, especially GPUs. I'm always keeping up with the latest tech news and innovations.
RAG & LLM
I enjoy building data extraction systems based on AI models. I've primarily worked with LangChain4j and LangChain, where I've built a complete ingestion pipeline.
Cycling
My bike: Romet Mustang M1 CS 19" 29". I enjoy riding both off-road and road routes.
Gym
I've recently started my journey with strength training. I find that the discipline required in the gym complements the focus needed for development. It's a great way to balance a sedentary lifestyle, and seeing tangible results is a huge motivator.
# My Journey
1st Year: Foundations
Grasped the low-level data representation: binary arithmetic, bitwise operations, and boolean algebra. Simultaneously built a strong foundation in Object-Oriented Programming (OOP) using C#, focusing on clean code structures and type safety.
2nd Year: Algorithms & Full-Stack
Mastered standard Data Structures and Algorithms. Transitioned from theory to practice by developing desktop applications. Learned to design relational databases and handle application logic efficiently.
3rd Year: Specialization & Practice
Pivoted to the Java ecosystem to specialize in Enterprise Backend. Co-developed 'Cibaria' using Spring Boot and Angular, implementing industry-standard Git workflows.
4th Year: Thesis & Advanced Projects
I defended my Engineering Thesis in the final year of my Computer Science degree, then built 'Gamelog', a full-stack game backlog manager where I mastered Redis for high-performance data caching, and explored the intersection of backend and AI with 'LlamaTalks' – integrating LLMs (LangChain) with Java-based systems and vector databases.
Present: Professional Career (Since 2026)
Since June 2026 I've been a Junior Java Developer at Netcompany. I apply my engineering foundations to complex, large-scale systems while continuing to explore cutting-edge technologies like RAG and DevOps in my personal time.
Future: Growth & Specialization
I plan to pursue an extramural (weekend) Master's degree, ensuring full availability during business hours while deepening my CS expertise and specializing further in scalable architectures.
# My Philosophy
Clean Code
I believe in the DRY (Don't Repeat Yourself) principle. I write code that is not only functional but also clean, maintainable, and easy for others to understand.
Continuous Learning
The tech world is constantly evolving, and I'm committed to growing with it. Every project is an opportunity to learn something new and improve my skills.
Problem-Solving
I see myself as a problem-solver first. I enjoy analyzing complex challenges and designing elegant, efficient solutions.
# My Setup
# Gear List
PC
- CPU: Ryzen 7 5800X3D
- RAM: 32GB Trident Z 3200Mhz
- MOBO: B450 Gigabyte Aorus Elite
- GPU: RTX 4070 Super Aorus Master
- SSD 1: Patriot P400 Lite 1TB
- SSD 2: Lexar NM620 2TB
- Case: NZXT H7 Flow
- Cooler: Arctic Liquid Freezer III 360mm
Peripherals
- Keyboard: Custom (Case 5075 VIA, Akko Botany switches, BoW Keycaps)
- Mouse: Dark project Nexus
- Monitors:
iiyama GB3461WQSUAlienware AW3425DW & PL2470HS - Microphone: Novox NC1
- Headphones: Arctis 7 & Airpods 2 Pro
Laptop
- Macbook Pro 14" (M1 Pro, 10c CPU, 16c GPU, 16GB RAM, 1TB SSD)