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Senior Full Stack Software Engineer with 8+ years of experience designing, modernizing, and integrating enterprise software solutions across fintech, insurance, healthcare, logistics, and digital platforms. Skilled in building scalable mobile applications, backend APIs, and secure AI-enabled workflows. Currently helping modernize legacy banking and insurance systems by transforming monolithic .NET platforms into modular, API-driven, AI-ready architectures—while also delivering production-grade mobile apps (Flutter) and web portals that integrate seamlessly with enterprise services.…Senior Full Stack Software Engineer with 8+ years of experience designing, modernizing, and integrating enterprise software solutions across fintech, insurance, healthcare, logistics, and digital platforms. Skilled in building scalable mobile applications, backend APIs, and secure AI-enabled workflows. Currently helping modernize legacy banking and insurance systems by transforming monolithic .NET platforms into modular, API-driven, AI-ready architectures—while also delivering production-grade mobile apps (Flutter) and web portals that integrate seamlessly with enterprise services.

Nicholas Otieno

Full Stack Developer, Back-End Developer, Software Engineer, +1

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Senior Full Stack Software Engineer with 8+ years of experience designing, modernizing, and integrating enterprise software solutions across fintech, insurance, healthcare, logistics, and digital platforms. Skilled in building scalable mobile applications, backend APIs, and secure AI-enabled workflows. Currently helping modernize legacy banking and insurance systems by transforming monolithic .NET platforms into modular, API-driven, AI-ready architectures—while also delivering production-grade mobile apps (Flutter) and web portals that integrate seamlessly with enterprise services.…Senior Full Stack Software Engineer with 8+ years of experience designing, modernizing, and integrating enterprise software solutions across fintech, insurance, healthcare, logistics, and digital platforms. Skilled in building scalable mobile applications, backend APIs, and secure AI-enabled workflows. Currently helping modernize legacy banking and insurance systems by transforming monolithic .NET platforms into modular, API-driven, AI-ready architectures—while also delivering production-grade mobile apps (Flutter) and web portals that integrate seamlessly with enterprise services.

Available to hire

Senior Full Stack Software Engineer with 8+ years of experience designing, modernizing, and integrating enterprise software solutions across fintech, insurance, healthcare, logistics, and digital platforms. Skilled in building scalable mobile applications, backend APIs, and secure AI-enabled workflows.

Currently helping modernize legacy banking and insurance systems by transforming monolithic .NET platforms into modular, API-driven, AI-ready architectures—while also delivering production-grade mobile apps (Flutter) and web portals that integrate seamlessly with enterprise services.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Language

English

Advanced

Swahili

Advanced

Work Experience

Full Stack Software Engineer at Pen soft Systems Limited

May 2, 2025 - Present

Develops and modernizes enterprise solutions for banking, insurance, healthcare, travel, and pensions. Contributes to transforming legacy platforms built on .NET into modular, API-driven architectures. Designs and maintains secure REST APIs using C#, ASP.NET, and SQL Server. Builds cross-platform mobile applications using Flutter for Android and iOS, and enhances the Africa Bim a mobile application and web portal for digital insurance policy management. Implements authentication/authorization and payment integrations including M-Pesa workflows. Integrates enterprise systems with mobile apps, third-party services, and AI-enabled workflows using modern integration patterns such as MCP. Optimizes performance through database query and backend service tuning, and collaborates with product managers, designers, QA engineers, and DevOps teams to deliver production-quality solutions.

Senior Software Engineer (Consultant & Contractor)

October 1, 2016 - December 1, 2025

Delivered mobile, backend, and enterprise solutions for fintech, logistics, healthcare, and SaaS clients across Europe, Africa, and North America. Led distributed frontend teams to build and deploy core MVP fintech applications using Flutter, improving launch timelines and team productivity. Contributed to multiple projects including modernization and refactoring efforts, cross-platform Flutter development, internal tooling improvements, and production delivery of stable iOS/Android applications ahead of schedule. Also worked on feature-rich cross-platform entertainment applications with strong defect tracking and bug elimination.