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Hello! I'm Mark C. Clark, a Senior Software Engineer with over 12 years of experience designing and scaling distributed systems and modern web and mobile applications. I specialize in building robust, scalable platforms using Java, Python, C#, .NET, React, and React Native, across fintech and SaaS domains. I enjoy turning complex problems into clean, maintainable code and helping teams ship features that matter. I have deep expertise delivering cross-platform mobile apps for iOS and Android with React Native and TypeScript, and architecting cloud-native backends on AWS. I thrive in collaborative environments, lead high-impact initiatives, and focus on performance optimizations that drive real business outcomes. I'm passionate about mentoring engineers, improving code quality, and delivering reliable, measurable results.…Hello! I'm Mark C. Clark, a Senior Software Engineer with over 12 years of experience designing and scaling distributed systems and modern web and mobile applications. I specialize in building robust, scalable platforms using Java, Python, C#, .NET, React, and React Native, across fintech and SaaS domains. I enjoy turning complex problems into clean, maintainable code and helping teams ship features that matter. I have deep expertise delivering cross-platform mobile apps for iOS and Android with React Native and TypeScript, and architecting cloud-native backends on AWS. I thrive in collaborative environments, lead high-impact initiatives, and focus on performance optimizations that drive real business outcomes. I'm passionate about mentoring engineers, improving code quality, and delivering reliable, measurable results.

Mark C Clark

Full Stack Developer, Back-End Developer, Front-End Developer, +2

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Hello! I'm Mark C. Clark, a Senior Software Engineer with over 12 years of experience designing and scaling distributed systems and modern web and mobile applications. I specialize in building robust, scalable platforms using Java, Python, C#, .NET, React, and React Native, across fintech and SaaS domains. I enjoy turning complex problems into clean, maintainable code and helping teams ship features that matter. I have deep expertise delivering cross-platform mobile apps for iOS and Android with React Native and TypeScript, and architecting cloud-native backends on AWS. I thrive in collaborative environments, lead high-impact initiatives, and focus on performance optimizations that drive real business outcomes. I'm passionate about mentoring engineers, improving code quality, and delivering reliable, measurable results.…Hello! I'm Mark C. Clark, a Senior Software Engineer with over 12 years of experience designing and scaling distributed systems and modern web and mobile applications. I specialize in building robust, scalable platforms using Java, Python, C#, .NET, React, and React Native, across fintech and SaaS domains. I enjoy turning complex problems into clean, maintainable code and helping teams ship features that matter. I have deep expertise delivering cross-platform mobile apps for iOS and Android with React Native and TypeScript, and architecting cloud-native backends on AWS. I thrive in collaborative environments, lead high-impact initiatives, and focus on performance optimizations that drive real business outcomes. I'm passionate about mentoring engineers, improving code quality, and delivering reliable, measurable results.

Available to hire

Hello! I’m Mark C. Clark, a Senior Software Engineer with over 12 years of experience designing and scaling distributed systems and modern web and mobile applications. I specialize in building robust, scalable platforms using Java, Python, C#, .NET, React, and React Native, across fintech and SaaS domains. I enjoy turning complex problems into clean, maintainable code and helping teams ship features that matter.

I have deep expertise delivering cross-platform mobile apps for iOS and Android with React Native and TypeScript, and architecting cloud-native backends on AWS. I thrive in collaborative environments, lead high-impact initiatives, and focus on performance optimizations that drive real business outcomes. I’m passionate about mentoring engineers, improving code quality, and delivering reliable, measurable results.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Language

English

Fluent

Work Experience

Software Engineer at PayPal

August 1, 2011 - June 1, 2014

Developed secure payment processing system using Java and backend architectures within large-scale financial platforms, supporting 5M+ transactions per day. Optimized algorithms and database interactions to reduce latency by ~25%, and collaborated with cross-functional teams to translate business requirements into scalable technical solutions delivering 10+ critical payment features. Resolved production issues and improved system stability to reduce incident resolution time by ~30%.

Senior Staff Software Engineer at Nike

July 1, 2014 - June 1, 2017

Led design and delivery of scalable enterprise systems by leveraging Java, Python, AWS cloud services, and microservices architecture, resulting in 44% improvement in system performance and scalability. Architected cloud-native applications using AWS, Docker, Kubernetes, and GraphQL APIs, achieving a 25% reduction in latency and 99.99% service availability. Developed high-performance backend services and optimized system throughput; implemented caching and database tuning to further improve performance. Collaborated with product and design teams to deliver frontend components using React and TypeScript integrated with GraphQL APIs, improving user engagement by 17%. Mentored 8–12 engineers and promoted best practices to accelerate delivery.

Staff Software Engineer at Slack

June 1, 2017 - August 1, 2022

Led development of scalable backend systems using Java, C#, and AWS infrastructure with a microservices architecture supporting 10M+ daily active users and 99.99% uptime. Designed APIs using GraphQL and REST technologies integrated with React and TypeScript-based frontend. Improved system reliability through monitoring, alerting, and fault-tolerant architectures; reduced production incidents. Mentored 5–8 engineers and fostered cross-functional collaboration to improve delivery velocity.

Senior Software Engineer

August 1, 2022 - Present

Led design and delivery of scalable enterprise systems by leveraging Java, Python, AWS cloud services, and microservice architecture; architected cloud-native applications using AWS, Docker, Kubernetes, and GraphQL APIs, enhancing performance and reliability. Built high-performance backend services and frontend solutions using React and TypeScript integrated with GraphQL APIs. Mentored teams, championed best practices, and drove cross-functional collaboration to meet business objectives.

Senior Software Engineer at PayPal

July 1, 2014 - June 2, 2017

Led cross-functional initiatives; designed scalable technical solutions delivering 20+ major features on schedule. Built backend services using Java, Python, REST APIs, and GraphQL; mentored 5-8 engineers; advanced engineering culture and cross-team alignment.

Senior Software Engineer

June 1, 2017 - August 1, 2022

Led development of scalable backend systems using Java, C#, and AWS; built scalable frontend components using React and TypeScript; optimized database queries; improved platform performance and reliability; collaborated with product teams to deliver high-impact features.

Senior Software Engineer

July 1, 2014 - June 1, 2017

Developed scalable application features using Java, C# and .NET; integrated REST and GraphQL APIs; built responsive frontend using React and TypeScript; improved UI performance and maintainability.