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Senior Full Stack & Mobile Engineer with 10+ years of experience delivering cross-platform mobile apps and responsive web platforms. Specialized in React Native, Flutter, and web (React/Next.js) with backends in Node.js, Python, and Firebase. Adept at building quiz/e-learning systems, scalable databases, and secure authentication with user progress tracking. Skilled in creating child-friendly UIs, seamless account synchronization, and deploying production apps to iOS, Android, and web. Strong background in cloud (AWS, Azure, GCP), CI/CD automation, and WCAG-compliant design.…Senior Full Stack & Mobile Engineer with 10+ years of experience delivering cross-platform mobile apps and responsive web platforms. Specialized in React Native, Flutter, and web (React/Next.js) with backends in Node.js, Python, and Firebase. Adept at building quiz/e-learning systems, scalable databases, and secure authentication with user progress tracking. Skilled in creating child-friendly UIs, seamless account synchronization, and deploying production apps to iOS, Android, and web. Strong background in cloud (AWS, Azure, GCP), CI/CD automation, and WCAG-compliant design.

Mark Wlodawski

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Senior Full Stack & Mobile Engineer with 10+ years of experience delivering cross-platform mobile apps and responsive web platforms. Specialized in React Native, Flutter, and web (React/Next.js) with backends in Node.js, Python, and Firebase. Adept at building quiz/e-learning systems, scalable databases, and secure authentication with user progress tracking. Skilled in creating child-friendly UIs, seamless account synchronization, and deploying production apps to iOS, Android, and web. Strong background in cloud (AWS, Azure, GCP), CI/CD automation, and WCAG-compliant design.…Senior Full Stack & Mobile Engineer with 10+ years of experience delivering cross-platform mobile apps and responsive web platforms. Specialized in React Native, Flutter, and web (React/Next.js) with backends in Node.js, Python, and Firebase. Adept at building quiz/e-learning systems, scalable databases, and secure authentication with user progress tracking. Skilled in creating child-friendly UIs, seamless account synchronization, and deploying production apps to iOS, Android, and web. Strong background in cloud (AWS, Azure, GCP), CI/CD automation, and WCAG-compliant design.

Available to hire

Senior Full Stack & Mobile Engineer with 10+ years of experience delivering cross-platform mobile apps and responsive web platforms. Specialized in React Native, Flutter, and web (React/Next.js) with backends in Node.js, Python, and Firebase. Adept at building quiz/e-learning systems, scalable databases, and secure authentication with user progress tracking. Skilled in creating child-friendly UIs, seamless account synchronization, and deploying production apps to iOS, Android, and web. Strong background in cloud (AWS, Azure, GCP), CI/CD automation, and WCAG-compliant design.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Language

English

Fluent

Work Experience

Senior Software Engineer at IMTS

June 1, 2025 - September 10, 2025

Developed cross-platform quiz and training apps in React Native and Flutter, paired with React web portals, enabling synchronized learning across devices. Built Firebase- and PostgreSQL-backed databases supporting 1,000+ questions per subject with score tracking, user progress, and analytics dashboards. Implemented child-friendly interfaces modeled after platforms like Plabable, with simplified navigation and WCAG accessibility. Integrated secure authentication (OAuth2, Firebase Auth, JWT) and cloud sync, ensuring students could switch between devices seamlessly. Automated CI/CD pipelines for iOS, Android, and web apps with GitHub Actions + Firebase App Distribution, reducing release cycles by 40%. Collaborated with academic stakeholders to design feedback-driven quiz flows, enhancing learning retention and usability.

Senior Software Engineer at Third Eye Software

March 31, 2024 - September 10, 2025

Built a cross-platform e-learning engine with React (web), React Native (mobile), and Node.js/Python APIs powering quiz delivery and progress tracking. Architected scalable backend services with Kafka + PostgreSQL, supporting thousands of concurrent learners with real-time scoring updates. Designed shared UI component libraries for React/React Native, ensuring consistency between mobile and web quiz experiences. Implemented scorecards, leaderboards, and result feedback modules with real-time synchronization via WebSockets. Deployed multi-region solutions on AWS + Azure, leveraging CDN caching for low-latency quiz delivery worldwide. Conducted UX research with students and teachers to refine quiz interfaces, improving engagement and retention metrics.

Senior Frontend Engineer at Optomi

December 31, 2022 - September 10, 2025

Delivered React Native quiz apps and web dashboards in React, integrated with Node.js APIs for real-time student scoring. Established a design system with Storybook, enabling rapid delivery of child-friendly UIs with accessibility in mind. Built offline-first quiz features in React Native and PWAs, allowing uninterrupted use in low-connectivity classrooms. Designed secure biometric and token-based login flows (Face ID, Touch ID, JWT), balancing ease-of-use and compliance. Automated testing pipelines (Jest, Cypress, Detox) to validate quiz logic, scoring accuracy, and UI stability. Partnered with educators to run A/B tests on quiz difficulty and feedback styles, improving learner outcomes.

Full Stack Engineer at Toptal

November 30, 2021 - September 10, 2025

Delivered educational and quiz-based apps with React, React Native, and Node.js, including scoring and reporting modules for learners. Built REST + GraphQL APIs serving question banks and student results, optimized with PostgreSQL and MySQL indexing. Integrated Firebase Auth and Firestore for user accounts, progress tracking, and device synchronization. Designed multi-tenant SaaS platforms with quiz libraries supporting thousands of concurrent learners across clients. Containerized deployments with Docker + Jenkins CI/CD, enabling smooth rollouts to cloud (AWS + GCP). Created real-time observability dashboards (Prometheus, Grafana) to monitor student activity and app health.