Cross-Platform App Backend Development

I am seeking a skilled developer for backend and integration work on a cross-platform app (iOS and Android).

Key Requirements:
- node.js
- Implement user authentication
- Manage database using Firebase
- Handle API integrations

Ideal Skills and Experience:
- Proven experience in backend development for mobile apps
- Proficiency in Firebase
- Strong understanding of user authentication and database management
- Experience with API integrations