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Jan Wiśniewski

Fullstack Developer

Jan Wiśniewski

I'm a Fullstack Developer and IT Delivery Engineer with 5+ years of experience building scalable, event-driven systems. At Raiffeisen Bank International I develop FX platform solutions on a microservices stack — Java 21+, Spring Boot, Apache Kafka — paired with Angular on the frontend. I'm also actively integrating AI tooling into my development workflow: Claude Code, GitHub Copilot, and multi-agent systems built on MCP.

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What I Do

Backend Architecture

Designing high-throughput microservices for financial platforms where reliability is non-negotiable. Java 21+, Spring Boot, Apache Kafka and Pulsar for event streaming — with CQRS, Flowable, Camunda, and a strict shift-left testing approach.

Frontend Development

Building responsive, modern user interfaces with Angular (21+), TypeScript, and JavaScript. Translating design mockups (Figma) into functional, interactive web applications.

AI-Augmented Development

Designing and orchestrating multi-agent AI workflows that integrate into the full software development lifecycle. Building systems where specialized agents handle backend, frontend, and code review tasks autonomously.

Agile & Quality

Delivering in two-week Scrum sprints with a shift-left testing mindset. Writing unit and integration tests (JUnit, Mockito) and conducting thorough code reviews to keep quality high from day one.

Resume

5+ Years of Experience

Delivered solutions for

raiffeisen-international
rars2
jsw
pana2
ro

Experience

07.2023 - Current
Raiffeisen Tech Warsaw

IT Delivery Engineer

  • Core Backend Development: Developing scalable microservices using Java 21+ and Spring Boot, utilizing Apache Kafka and Pulsar for asynchronous, event-driven communication.
  • Business Logic Implementation: Modeling complex workflows and decision rules using Flowable and Camunda decision tables.
  • Quality & DevOps: Advocating for shift-left testing (SBE, Unit, Integration tests) and maintaining CI/CD pipelines with Jenkins and Docker.
  • Fullstack & Agile: contributing to Angular frontend development (based on Figma) and actively participating in Scrum ceremonies to refine technical requirements.
11.2020 - 06.2023
Red Ocean Warsaw

Fullstack Developer

  • Requirements Analysis: Collaborated with analysts and independently translated client requirements into technical specifications.
  • Fullstack Development: Designed database models and implemented business logic using Java & Spring Boot, while integrating them with Angular frontend components.
  • UI Implementation: Developed user interfaces based on Figma designs, ensuring consistency with visual projects.
  • Maintenance: Optimized application performance, maintained existing projects, and resolved bugs to ensure system stability.
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Education

2019 - 2020
Warsaw University of Technology

Postgraduate Studies: Java EE Software Development

  • Focus on enterprise software production and Java ecosystem.
2015 – 2017
University of Warsaw

Master of Arts in Journalism and Media Studies

  • Specialization in media analysis and communication
2012 - 2015
University of Warsaw

Bachelor of Arts in Journalism and Social Communication

AI

  • Claude Code
  • Github Copilot
  • MCP Servers
  • Skills for Agents
  • Agentic Coding

Coding

  • Java 21+
  • Spring Boot
  • Angular 12+
  • Javascript
  • Typescript

Architecture

  • Microservices
  • CQRS
  • Camunda
  • Flowable
  • Apache Kafka
  • Pulsar
  • DDD
  • REST

Databases

  • JPA
  • Hibernate
  • SQL
  • Postgres
  • MongoDB

DevOps

  • Docker
  • Jenkins
  • Maven
  • Gradle
  • Prometheus
  • Grafana
  • OpenSearch

Testing

  • JUnit
  • Mockito
  • Jest
  • Rest Assured
  • WebdriverIO

Contact

Get in Touch

How Can I Help You?