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I’m Damian Marzec, a Full Stack Software Engineer with over 10 years of experience building scalable, end-to-end applications across AI, fintech, and enterprise platforms. I specialize in both backend and frontend development, working extensively with Node.js, TypeScript, NestJS, and React to deliver complete, production-ready solutions. Throughout my career, I’ve taken ownership of the full development lifecycle—designing system architecture, building robust APIs, and creating intuitive, high-performance user interfaces. In my most recent role, I developed AI-powered healthcare applications, integrating LLM-driven conversational systems on the backend while also building responsive dashboards on the frontend used by clinicians in real time. Previously, I worked in fintech, where I built full stack payment platforms, implemented secure KYC/AML integrations, and developed seamless user experiences for large-scale customer bases. What makes me stand out is my ability to bridge backend complexity with frontend usability. I don’t just build services or interfaces in isolation—I ensure everything works together as a cohesive product. I bring a strong product mindset, rapid prototyping ability, and a focus on delivering features that are both technically sound and highly impactful for users.…I’m Damian Marzec, a Full Stack Software Engineer with over 10 years of experience building scalable, end-to-end applications across AI, fintech, and enterprise platforms. I specialize in both backend and frontend development, working extensively with Node.js, TypeScript, NestJS, and React to deliver complete, production-ready solutions. Throughout my career, I’ve taken ownership of the full development lifecycle—designing system architecture, building robust APIs, and creating intuitive, high-performance user interfaces. In my most recent role, I developed AI-powered healthcare applications, integrating LLM-driven conversational systems on the backend while also building responsive dashboards on the frontend used by clinicians in real time. Previously, I worked in fintech, where I built full stack payment platforms, implemented secure KYC/AML integrations, and developed seamless user experiences for large-scale customer bases. What makes me stand out is my ability to bridge backend complexity with frontend usability. I don’t just build services or interfaces in isolation—I ensure everything works together as a cohesive product. I bring a strong product mindset, rapid prototyping ability, and a focus on delivering features that are both technically sound and highly impactful for users.

Damian Marzec

Full Stack Developer, Back-End Developer, Front-End Developer, +4

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I’m Damian Marzec, a Full Stack Software Engineer with over 10 years of experience building scalable, end-to-end applications across AI, fintech, and enterprise platforms. I specialize in both backend and frontend development, working extensively with Node.js, TypeScript, NestJS, and React to deliver complete, production-ready solutions. Throughout my career, I’ve taken ownership of the full development lifecycle—designing system architecture, building robust APIs, and creating intuitive, high-performance user interfaces. In my most recent role, I developed AI-powered healthcare applications, integrating LLM-driven conversational systems on the backend while also building responsive dashboards on the frontend used by clinicians in real time. Previously, I worked in fintech, where I built full stack payment platforms, implemented secure KYC/AML integrations, and developed seamless user experiences for large-scale customer bases. What makes me stand out is my ability to bridge backend complexity with frontend usability. I don’t just build services or interfaces in isolation—I ensure everything works together as a cohesive product. I bring a strong product mindset, rapid prototyping ability, and a focus on delivering features that are both technically sound and highly impactful for users.…I’m Damian Marzec, a Full Stack Software Engineer with over 10 years of experience building scalable, end-to-end applications across AI, fintech, and enterprise platforms. I specialize in both backend and frontend development, working extensively with Node.js, TypeScript, NestJS, and React to deliver complete, production-ready solutions. Throughout my career, I’ve taken ownership of the full development lifecycle—designing system architecture, building robust APIs, and creating intuitive, high-performance user interfaces. In my most recent role, I developed AI-powered healthcare applications, integrating LLM-driven conversational systems on the backend while also building responsive dashboards on the frontend used by clinicians in real time. Previously, I worked in fintech, where I built full stack payment platforms, implemented secure KYC/AML integrations, and developed seamless user experiences for large-scale customer bases. What makes me stand out is my ability to bridge backend complexity with frontend usability. I don’t just build services or interfaces in isolation—I ensure everything works together as a cohesive product. I bring a strong product mindset, rapid prototyping ability, and a focus on delivering features that are both technically sound and highly impactful for users.

Available to hire

I’m Damian Marzec, a Full Stack Software Engineer with over 10 years of experience building scalable, end-to-end applications across AI, fintech, and enterprise platforms. I specialize in both backend and frontend development, working extensively with Node.js, TypeScript, NestJS, and React to deliver complete, production-ready solutions.

Throughout my career, I’ve taken ownership of the full development lifecycle—designing system architecture, building robust APIs, and creating intuitive, high-performance user interfaces. In my most recent role, I developed AI-powered healthcare applications, integrating LLM-driven conversational systems on the backend while also building responsive dashboards on the frontend used by clinicians in real time. Previously, I worked in fintech, where I built full stack payment platforms, implemented secure KYC/AML integrations, and developed seamless user experiences for large-scale customer bases.

What makes me stand out is my ability to bridge backend complexity with frontend usability. I don’t just build services or interfaces in isolation—I ensure everything works together as a cohesive product. I bring a strong product mindset, rapid prototyping ability, and a focus on delivering features that are both technically sound and highly impactful for users.

Skills

Experience Level

Expert

Expert

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Expert

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Expert

Expert

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Expert

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Expert

Expert

Expert

Expert

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Language

Polish

Fluent

English

Fluent

Work Experience

Senior Full Stack Engineer at Indra

May 1, 2022 - Present

Led the migration of an AI-powered educational platform from on-premises to AWS, ensuring minimal downtime and smooth transfer of critical features including self-marking tools and chatbots. Designed and implemented scalable backend services using Node.js and Python, enabling high concurrency on large datasets. Integrated AI-driven assessment tools into the platform, improving automation for marking and feedback, and collaborated with frontend teams to ensure seamless UI integration with React-based components and data visualizations. Optimized AI models for performance, reducing query times and increasing accuracy of self-marking assessments. Implemented secure authentication (OAuth) and RESTful APIs; built and maintained CI/CD pipelines to automate deployments and accelerate feature delivery. Drove migration to AWS Lambda, S3, and other serverless components, and supported mobile performance optimizations using React Native.

Senior Full Stack Engineer at Global IT Associates LLC

March 1, 2022 - October 6, 2025

Contributed to migrating an education platform to Google Cloud, optimizing system performance, scalability, and reliability. Designed and built AI-powered tooling including self-marking quizzes and chatbots, leveraging Node.js, TypeScript, and Redux; integrated with React-based frontend. Implemented event-driven architecture with Kafka for real-time processing and developed RESTful APIs with Node.js and Python. Automated deployments with CI/CD pipelines and containerized services using Docker and Kubernetes; deployed on Google Cloud resources. Built analytics dashboards for administrators and instructors and collaborated with AI specialists to enhance AI-driven assessments.

Back End Engineer at Survicate

July 1, 2017 - October 6, 2025

Developed AI-powered backend services and APIs for education tools, focusing on real-time user support through NLP-driven chatbots. Implemented backend with Node.js and Python; set up data storage with PostgreSQL and NoSQL databases. Built RESTful APIs and data pipelines; created unit and integration tests; contributed to API design and security considerations with OAuth flows. Built and maintained self-marking features and collaborated with frontend developers for UI integration. Wrote tests and ensured scalable, maintainable code.

Senior Software Engineer at Infermedica

March 1, 2025 - February 1, 2026

Led development of a large-scale healthcare diagnostic platform using React.js, TypeScript, Redux, and Next.js, solving complex UI state synchronization issues across multiple microfrontends while integrating AI-driven symptom analysis services and ensuring real-time responsiveness for over 20,000 daily users. Architected a component-driven frontend system with Storybook and design tokens, improving cross-team UI consistency and reducing duplicate component usage across 5 engineering teams. Built scalable REST API integrations with Node.js and backend services, handling asynchronous workflows and improving data fetching efficiency through optimized caching strategies. Implemented advanced performance optimization techniques including code splitting, lazy loading, and bundle analysis, reducing application load time across multiple regions. Designed and enforced WCAG 2.1 accessibility standards and multilingual support across European healthcare applications. Integrated AI-assisted devel

Full Stack Engineer at Paypo

April 1, 2022 - February 1, 2025

Developed fintech payment solutions using React.js, TypeScript, Node.js, and Redux, handling secure transaction flows and integrating Stripe and PayPal. Tackled AI-driven fraud detection challenges by integrating machine learning APIs and building real-time monitoring dashboards. Designed RESTful APIs and backend services with NestJS and PostgreSQL, supporting high-volume financial transactions and ensuring reliability. Built scalable frontend systems with Zustand and modern React patterns, implemented CI/CD pipelines with Docker, and integrated KYC/AML verification systems for compliant onboarding. Implemented testing strategies with Jest and Cypress to maintain platform stability and collaborated with cross-functional teams.

Software Engineer at Cormarch

July 1, 2019 - March 1, 2022

Delivered enterprise-grade web applications using React.js, JavaScript, and Redux for business management systems. Built REST APIs and backend services with Node.js and Express.js, ensuring scalable and maintainable architectures. Implemented responsive UI components and optimized database queries with PostgreSQL and Redis. Introduced unit testing practices with Jest and contributed to Agile development processes. Collaborated with frontend and backend teams to deliver integrated solutions.

Software Developer at Netizens

November 1, 2015 - June 1, 2019

Developed web applications using JavaScript, React.js, and PHP, supporting various client-facing platforms. Built reusable UI components, improved frontend performance, and designed backend services with PHP and MySQL. Implemented RESTful APIs and integrated third-party services. Performed debugging and troubleshooting across production applications and contributed to Agile workflows.