Backend Development and Integration for React and Flutter Apps

I'm seeking a skilled backend developer to enhance and integrate an existing Supabase and PostgreSQL backend for my React web app and Flutter app. The current system features a complex 7-level hierarchical structure that tracks items in a rollup fashion while respecting parent/child relationships.

Key Requirements:
- Maintain a complex 7-level hierarchical database structure.
- Ensure user selections dynamically update parent counts.
- Integrate backend with three frontend pages, ensuring an intuitive design.
- Generate detailed reports for individual users, including:
- Progress charts
- Custom query results
- Enable supervisors to generate detailed reports for all their users in both a single Excel file and individual Excel files. Reports will include:
- User progress metrics
- User custom query results

Ideal Skills and Experience:
- Proficiency in Supabase and PostgreSQL
- Strong experience in backend development for React and Flutter applications
- Database design and integration
- Report generation and data aggregation in Excel
- Ability to create intuitive, user-friendly interfaces

Looking for someone who can deliver a robust, well-integrated backend solution that meets these requirements.