Jan Kowalski
I'm Jan Kowalski, a Senior Full-Stack Engineer with 11 years of experience delivering scalable, high-performance web applications and cloud-based solutions.
About
I’m Jan Kowalski, a Senior Full-Stack Engineer with 11 years of experience delivering scalable, high-performance web applications and cloud-based solutions. I excel at bridging frontend and backend teams, mentoring developers, and driving product innovation in fast-paced environments.
I have strong expertise across React, Next.js, Node.js, Python, and cloud platforms like AWS, Azure, and GCP, with a proven ability to design robust microservices, integrate complex APIs, and optimize performance end-to-end.
- 7 years' experience
- Joined October 2025
Industry experience
- Software & Internet
- Healthcare
- Retail
- Real Estate & Construction
- Professional Services
Work experience· 9 roles
Led the design and development of healthcare dashboards and patient engagement portals using React, Next.js and TypeScript, with secure backend integration via Node.js and Python APIs. Implemented role-based authentication and authorization with Firebase Auth, ensuring secure handling of sensitive healthcare data. Integrated RESTful and GraphQL APIs to connect clinical systems with real-time patient data, improving care team efficiency. Developed interactive data visualization features with D3.js and Chart.js, enabling healthcare providers to monitor patient vitals in real time. Optimized performance with server-side rendering, lazy loading and code splitting, reducing load times and improving reliability. Mentored junior engineers, promoted adoption of TDD, and improved code quality through peer reviews.
Led the design and development of healthcare dashboards and patient engagement portals using React, Next.js, and TypeScript, with secure backend integration via Node.js and Python APIs. Implemented role-based authentication and authorization with Firebase Auth, ensuring secure handling of sensitive healthcare data. Integrated RESTful and GraphQL APIs to connect clinical systems with real-time patient data, improving care team efficiency. Developed interactive data visualization features with D3.js and Chart.js for real-time vitals monitoring. Optimized performance with server-side rendering, lazy loading, and code-splitting, reducing load times and improving reliability. Mentored junior engineers and promoted TDD and code quality through peer reviews.
Led design and development of healthcare dashboards and patient engagement portals using React, Next.js, and TypeScript, with secure backend integration via Node.js and Python APIs. Implemented role-based authentication and authorization with FirebaseAuth for secure handling of healthcare data. Integrated RESTful and GraphQL APIs to connect clinical systems with real-time patient data, improving care team efficiency. Developed interactive data visualizations with D3.js and Chart.js for real-time vitals monitoring. Optimized performance with server-side rendering, lazy loading, and code-splitting, reducing load times and increasing reliability. Mentored junior engineers, promoted TDD, and improved code quality through peer reviews.
Education
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