Olowonishaye S.

Full stack developer with 10 years of experience | Top Rated on Upwork ✅ I turn ideas into real applications your users can depend on 💡 
 Clients consistently describe me as a reliable, solution-oriented developer who delivers quality work, communicates clearly, and takes ownership of project outcomes. With hands-on experience across React Native, React, Next.js, and full-stack development, I help clients turn ideas into functional, production-ready applications.
 My track record includes joining existing codebases and contributing immediately, debugging complex authentication issues, improving web and mobile applications, integrating databases and calendars, and helping clients transform broad requirements into workable products. Clients appreciate my responsiveness, attention to detail, collaborative approach, and commitment to going beyond expectations.

I focus on building practical solutions, resolving technical challenges efficiently, and ensuring every deliverable moves the project closer to its business goals. 

Recent work: 
 🔹 Maintained a 5.0-star client rating across multiple Upwork projects, with consistent praise for technical expertise, reliability, and quality delivery. 🔹 Built and enhanced React Native mobile applications, earning repeat engagements and client recommendations for going above and beyond. 🔹 Debugged and improved existing React.js and Next.js codebases, resolving authentication issues and helping clients get their applications working reliably. 🔹 Delivered full-stack web applications with frontend, backend, database, and calendar integrations, helping clients transform broad ideas into functional products. 🔹 Executed web and mobile QA testing, identifying critical bugs and edge cases that improved application quality before delivery. 🔹 Recognized for clear communication, fast execution, proactive problem-solving, and accountability—so you get a developer who takes ownership and focuses on getting your product shipped. 
Send me your repo or a quick walkthrough of your delivery flow (Figma → Jira → GitHub → review), and I'll come back with: 🔍 where your velocity is actually leaking - review bottlenecks, rework, estimates that never hold 🏗️ how your codebase really looks on quality, architecture, and performance 🤖 how much more your team could be getting out of AI than they are today You keep the findings whether we end up working together or not! Want to scope something, or should I just run the audit first? I usually reply within an hour 🚀 

 
Why should you hire me as a Full Stack Developer? 
 
▪ 10 years of experience in Next.js and Nuxt, with 8 years in Node.js and TypeScript across production systems. ▪ 200+ successful projects delivered for fintech, healthcare, e-commerce, HR tech, construction, logistics, and AI companies. 
▪ Strong experience with marketplaces, SaaS platforms, and internal HR and admin systems. 

▪ Proficient in Nuxt, React, Next.js, Node.js, TypeScript, Python, PostgreSQL, and AWS. 

 ▪ Experience with complex features like authentication and role-based access, real-time data handling, payment flows, search, and third-party integrations. 

 ▪ 500+ API endpoints and 50+ microservices designed, documented, and shipped to production. 

 ▪ 20+ legacy rescues and framework migrations completed with zero downtime

 ▪ 30+ production applications launched and still running. 
▪ Investor-ready MVPs delivered in 4-6 weeks for founders raising their first round. 
 
▪ Cross-platform products for web, mobile (iOS & Android), and desktop from one shared codebase. 

▪ 100+ code audits and architecture reviews delivered for founders, CTOs, and investors. ▪ 100% Job Success across years of client work, with 10+ clients.