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I am Damian Marzec, a senior software engineer with over 11 years of experience building robust, scalable full-stack web apps across healthcare, fintech, and e-commerce. I design reliable React/Node.js systems, backend services, and remote-friendly teams with clear communication and a bias for practical delivery. I thrive in part-time contract work that requires independent ownership, strong client communication, and flexible collaboration across time zones. I’ve nurtured a collaborative culture by mentoring teammates, supporting code reviews, and staying calm under pressure to ensure fast, predictable production releases.…I am Damian Marzec, a senior software engineer with over 11 years of experience building robust, scalable full-stack web apps across healthcare, fintech, and e-commerce. I design reliable React/Node.js systems, backend services, and remote-friendly teams with clear communication and a bias for practical delivery. I thrive in part-time contract work that requires independent ownership, strong client communication, and flexible collaboration across time zones. I’ve nurtured a collaborative culture by mentoring teammates, supporting code reviews, and staying calm under pressure to ensure fast, predictable production releases.

Damian Marzec

Full Stack Developer, Web Developer, Back-End Developer, +3

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I am Damian Marzec, a senior software engineer with over 11 years of experience building robust, scalable full-stack web apps across healthcare, fintech, and e-commerce. I design reliable React/Node.js systems, backend services, and remote-friendly teams with clear communication and a bias for practical delivery. I thrive in part-time contract work that requires independent ownership, strong client communication, and flexible collaboration across time zones. I’ve nurtured a collaborative culture by mentoring teammates, supporting code reviews, and staying calm under pressure to ensure fast, predictable production releases.…I am Damian Marzec, a senior software engineer with over 11 years of experience building robust, scalable full-stack web apps across healthcare, fintech, and e-commerce. I design reliable React/Node.js systems, backend services, and remote-friendly teams with clear communication and a bias for practical delivery. I thrive in part-time contract work that requires independent ownership, strong client communication, and flexible collaboration across time zones. I’ve nurtured a collaborative culture by mentoring teammates, supporting code reviews, and staying calm under pressure to ensure fast, predictable production releases.

Available to hire

I am Damian Marzec, a senior software engineer with over 11 years of experience building robust, scalable full-stack web apps across healthcare, fintech, and e-commerce. I design reliable React/Node.js systems, backend services, and remote-friendly teams with clear communication and a bias for practical delivery.

I thrive in part-time contract work that requires independent ownership, strong client communication, and flexible collaboration across time zones. I’ve nurtured a collaborative culture by mentoring teammates, supporting code reviews, and staying calm under pressure to ensure fast, predictable production releases.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Language

Polish

Fluent

English

Advanced

Work Experience

Senior Software Engineer at Infomedica

March 1, 2025 - February 1, 2026

Hybrid role focused on scalable Next.js and TypeScript patient-facing portals integrated with AI-driven symptom analysis APIs; optimized real-time data processing pipelines and reduced response latency by a significant margin while improving platform reliability under high concurrency. Implemented secure authentication and role-based access control using Supabase and PostgreSQL; deployed via Vercel.

Senior Software Engineer at Paypo

April 1, 2022 - February 1, 2025

Built high-volume fintech platform using Node.js, TypeScript, and React; processed over $50M monthly transactions; improved transaction throughput by 26% through backend optimizations and API integrations with payment gateways; designed secure authentication flows and robust RESTful APIs.

Software Engineer at Cormarch

July 1, 2019 - March 1, 2022

Developed enterprise backend services for telecom platforms; improved system throughput by 23% and integrated EDI and RESTful APIs; implemented scalable cloud infrastructure focusing on AWS; emphasized data integrity and reliability.

Software Developer at Netizens

November 1, 2015 - June 1, 2019

Implemented full-stack CRM and e-commerce features; streamlined customer management workflows, built responsive dashboards, and optimized data queries to improve performance and user experience across multiple browsers and devices.

Senior Software Engineer at Infermedica

March 1, 2025 - February 1, 2026

Developed interactive patient triage flows using React, TypeScript, and Node.js; integrated AI/ML APIs into symptom analysis workflows with structured JSON contracts, retry handling, and validation layers, reducing symptom-check latency and improving accuracy; implemented backend orchestration for AI-enabled medical API calls with NestJS, PostgreSQL, Redis, and RESTful services; enhanced real-time UX with streaming updates and resilient error handling; contributed to improved patient outcomes and system reliability.

Full Stack Engineer at Paypo

April 1, 2022 - February 1, 2025

Built scalable merchant checkout and customer payments portals using React, TypeScript, PHP Laravel, and Node.js; processed 50M+ monthly transactions; designed RESTful APIs, PostgreSQL, Redis, and third-party provider integrations for BNPL payment approvals; improved checkout responsiveness by 28% and reduced transaction latency; developed customer dashboards with secure payment histories; implemented CI/CD with Docker and GitHub Actions.

Senior Software Engineer at Informedica

March 1, 2025 - February 1, 2026

Developed high-performance React interfaces for symptom checker workflows, improving state management, component rendering, and clinical form responsiveness while reducing interaction delays by 31% across complex patient triage pathways.

Software Engineer at Netizens

November 1, 2015 - June 30, 2019

Created e-commerce platforms using PHP, Laravel, JavaScript, MySQL, and HTML5, improving page response times by 25% through query optimization and reusable frontend components. Built CRM and business management modules with React, and supported IoT and client data exchanges by debugging integrations and maintaining production fixes, contributing to stronger ownership and reliability.