FastAPI and Next.js Development

I have a fintech website, [login to view URL], that offers backtesting services for stock trading strategies. The site is built with [login to view URL] frontend and FastAPI backend. ScreeningTale is soon ready for launch, but I have discovered some weaknesses that have to be fixed first. One of the weaknesses is that authentication is currently handled with Next Auth in frontend via Google Sign-In, which introduces a few challenges. Both authentication and ratelimiting were functional, but it stopped working a while ago. Instead of fixing it, I want the authentication to be handled via our backend in FastAPI. The new solution should be paired up with the (completed) sign-in page on [login to view URL], which means that username/password login and registration, google sign-in, email verification and password reset should be covered. The user data should be stored in a database to be created at DigitalOcean. The task also involves adapting the ratelimiting code, and some existing endpoints to the new authentication scheme. Even though ScreeningTale is close to launch, I have a large backlog of features to be implemented at a later time. If I'm satisfied with the work on authentication, I will therefore preferably use the same freelancer for lots of future work on FastAPI and Next.js. For this reason, it is really beneficial if the freelancer is familiar with Next/React as well as FastAPI, Docker and PostgreSQL. I have no problem hiring from overseas:)