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$
USD
I will or fix your saas, fintech, or payment system using nextjs
Mark Gauden
About this gig
I'm a senior full-stack developer with over 7 years of experience building SaaS platforms, fintech systems, and scalable web applications.
I usually work on projects where things are a bit more complex, such as payment integrations, webhook handling, backend logic, or fixing issues in existing codebases. I focus less on simple template websites and more on real, production-ready systems.
I can help you build or improve SaaS products, integrate payment providers like Stripe and alternative methods, fix broken checkout or payment flows, and properly handle asynchronous payments and webhooks. I also work with Next.js, Cloudflare Workers, APIs, authentication, and performance improvements.
My main stack includes Next.js, React, TypeScript, Cloudflare Workers and Pages, Node.js, REST and GraphQL APIs, Tailwind CSS, and databases like PostgreSQL, D1, and Supabase.
This gig is ideal for SaaS founders, startups working on MVPs, fintech or payment-heavy products, and teams that already have a project but need reliable technical support.
I focus on clean architecture, security, and long-term maintainability.
Feel free to message me before ordering so we can discuss your requirements.
Respect third-party rights
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Get to know Mark Gauden
Mark Gauden
Senior Full Stack Engineer
- FromPhilippines
- Member sinceSep 2025
Languages
English
I’m a full stack developer with expertise in React, NextJS, Vue, Laravel, Node, and Strapi, along with deep experience in Stripe, PayPal, and Apple/Google Pay integrations. I also specialize in Web3, smart contracts, and NFT platforms using Ether and Solana. From responsive frontends to secure backends, I build scalable apps, custom dashboards, and dApps. I value clean code, clear communication, and on-time delivery. Let’s bring your idea to life with a reliable and modern solution.
My Portfolio
FAQ
Do you work on existing codebases?
Yes. I frequently work with legacy or partially built SaaS platforms.
Can you fix payment issues?
Yes. I specialize in payment flows, webhooks, and asynchronous payment confirmation.
Do you build MVPs?
Yes. I help founders go from idea to a production-ready MVP.
Do you provide ongoing support?
Yes, long-term collaboration is welcome.
