Rafał Chałupnik

• Built and maintained the backend for a mobile multiplayer game using C#/.NET, designing server-side systems to support real-time gameplay at scale
• Worked with a high-performance data layer with ScyllaDB and Redis, enabling the system to handle thousands of concurrent requests with low latency

• Built and improved distributed Daylight PMS and REST APIs in .NET, enabling seamless integrations between PMS and external hotel partners
• Designed and delivered scalable microservices leveraging Kafka for event-driven communication and AWS for cloud deployment
• Driven code quality and engineering standards through in-depth reviews, refactoring initiatives, and knowledge-sharing within the team
• Took ownership of complex integrations and greenfield projects, translating ambiguous business requirements into production-ready solutions

• Acted as technical lead and Scrum Master for a cross-functional team enhancing Titian’s Mosaic sample management platform used by top Big Pharma companies
• Designed and evolved architecture and REST APIs, improving reliability, scalability, and interoperability with third-party vendor systems
• Led key modernization initiatives, including migration from TFVC to Git and Bugzilla to Azure DevOps, establishing new workflows, branching strategies, and automation pipelines
• Championed code quality and engineering best practices, conducting in-depth reviews, mentoring developers, and introducing .NET features to improve maintainability
• Drove process and delivery improvements in CI/CD and agile practices, working closely with QA, DevOps, and product management to increase deployment confidence and delivery cadence
• Served as a technical reference point company-wide, advising teams on integration design, API development, and debugging complex production issues

• Designed and implemented interfaces with external vendor systems, ensuring stable data exchange and system compatibility across distributed environments
• Collaborated with QA and product teams to deliver reliable solutions within agile sprints
• Participated in technical recruitment and internal IT support, contributing to infrastructure reliability and onboarding improvements

• Contributed to the development and maintenance of service-oriented .NET applications supporting one of Poland’s largest debt and credit information databases
• Assisted in implementing backend modules and optimizing existing components to improve performance and maintainability
• Gained first hands-on experience with enterprise software delivery, version control, and agile collaboration practices while completing BSc studies

Wroclaw University of Science and Technology

March 2019 - July 2020

Wroclaw University of Science and Technology

October 2015 - January 2019

Towards Intelligent Human-Computer Interfaces: Simplified BCI for Subject Recognition

Rafal Chalupnik, Katarzyna Bialas

Multifactor Authentication System Using Simplified EEG Brain–Computer Interface

Katarzyna Bialas, Michal Kedziora, Rafal Chalupnik, Houbing Herbert Song

Using Simplified EEG-Based Brain Computer Interface and Decision Tree Classifier for Emotions Detection

Rafal Chalupnik, Katarzyna Bialas, Zofia Majewska, Michal Kedziora