Migration and Improvement of Fitness Platform

I need an experienced Full-Stack Developer to help migrate and improve Movesbook, an existing fitness and sports activity platform for athletes, coaches, teams, clubs and fitness enthusiasts.
The original platform was built with CakePHP and is currently being migrated to Next.js + Prisma to improve performance, scalability and maintainability.
Website: https://movesbook.net

Main Tasks
· Audit the current frontend UX and user flows, identify usability and design issues and provide clear recommendations for what should be improved or redesigned
· Continue the CakePHP → Next.js migration
· Develop and improve frontend and backend functionality
· Integrate and maintain APIs
· Work with Prisma and the existing database
· Implement and improve payment integration
· Fix bugs and improve performance
· Ensure migrated features work correctly with the existing system

Requirements
· Strong Next.js / React experience
· Good PHP / CakePHP knowledge
· Experience with Prisma and databases
· Strong API integration skills
· Payment gateway integration experience
· Comfortable working with and improving an existing codebase
Experience with fitness, sports, activity tracking or similar platforms is a plus.
This is an ongoing project, so we’re looking for someone interested in long-term collaboration and comfortable working across both frontend and backend.
Budget rate: $15–$20/hr
Please include your GitHub, portfolio or relevant previous work when applying.