Custom Video Call Solution Development - No 3rd Party Solution

I need a custom video call setup on my server or cloud.

Key Requirements:
- Support for iOS, Android, Windows, and Mac
- Enable both group and one-on-one calls
- Video call recording and viewing feature
- Customizable video calling screen

Important Notes:
- No third-party APIs or SDKs
- Preference for ready-built solutions

Ideal Skills:
- Experience in video conferencing development
- Strong backend and frontend development skills
- Familiarity with real-time communication protocols

If you have already built a similar solution, please highlight that in your bid.