Crafting robust systems,
building elegant products.
I'm Krzysztof Janiec, a Senior Software Engineer specializing in backend architecture, performant full-stack development, and developer-first design systems.
Distributed & Event-Driven Systems
Designed enterprise microservices at REWE Digital, Cinkciarz.pl, and Biot. Expert in transactional event streams (Kafka, RabbitMQ) and high-scale Java/Spring Boot & TypeScript/Node.js backends.
Performant UIs & Interactive Graphics
Created a custom 3D WebGL voxel engine in Babylon.js with chunk streaming (60 FPS), real-time collaborative workspace synchronization via WebSockets, and heavy analytical React & Angular UIs.
Experience
12+ yrs
Backend
Java & Node
Frontend
React & Angular
Services
What I Do & Deliver
I partner with teams to design, build, and optimize high-performance software systems. Here are the core services I provide.
Full-Stack Development
Building modern, performant web applications using React, Angular, Next.js, and TypeScript, backed by clean and scalable APIs.
System Architecture
Designing clean, decoupled, and pragmatic system architectures in Go, Python, or Rust built for long-term scalability.
Cloud & DevOps
Setting up automated CI/CD pipelines, container orchestration (Docker/Kubernetes), and secure AWS/GCP cloud environments.
Technical Consulting
Conducting technology evaluations, code audits, architecture reviews, and performance tuning to solve complex bottlenecks.
Portfolio
Featured Work
UI Kit & Design System
A premium React + TypeScript component library and token-driven design system. Built as a monorepo containing @kjaniec-dev/design for design tokens and @kjaniec-dev/ui for accessible, interactive components. Configured with Tailwind CSS v4, Storybook previews, and a standalone gallery, powering a cohesive visual language across my personal web projects.
Planning Poker Backend & App
Real-time collaborative estimation tool for agile teams. Built with a TypeScript/Node.js and Go WebSocket server cluster, with Redis pub/sub adapter for seamless multi-instance synchronization. Deployed on Kubernetes with horizontal scaling, supporting instant session coordination, active room management, and secure room auth.
MUI Greyscale Admin Dashboard
A comprehensive, production-ready admin dashboard template with a minimalist greyscale design. Covers 27 feature domains including CRM, finance, inventory, marketing, and security — all built with React 19, Material UI v9, and Vite 7. Fully open source and ready to use as a starting point for your next internal tool or admin panel.
Cyberpunk Voxel City - Interactive Resume
An interactive 3D resume disguised as a browser-based game. Explore a sprawling cyberpunk city rendered entirely from voxels, discovering skill boxes that represent technical expertise. Features custom voxel engine with greedy meshing, procedural city generation, dynamic lighting effects, and chunk-based streaming for smooth 60 FPS performance.