Backend providing API for apps.

I am looking for a backend developer to create an API for my apps. The ideal candidate should have experience in the following:

Programming Language:
- Golang

Functionality needed:
- User authentication and authorization

Database structure:
- Existing database integration

Skills and experience required:
- Strong proficiency in the chosen programming language
- Experience with user authentication and authorization
- Familiarity with integrating APIs (https://github.com/teslamotors/vehicle-command)