Building a Digital Membership Card System with .NET Web API

Hi developers,

I am working on a membership management platform using .NET Web API and exploring how modern organizations are moving from traditional physical cards to digital membership solutions.

The project focuses on features like digital membership cards, member authentication, loyalty programs, notifications, and integrations that can improve the overall member experience. Platforms like MembershipAnywhere are also helping museums, attractions, clubs, and organizations provide digital membership cards along with loyalty features and better engagement tools.

From a development perspective, I am interested in understanding the best architecture approach for building a scalable system that can handle thousands of members.

Some areas I am exploring:

1. Secure authentication and user management

2. API architecture and database design

3. Digital card generation and wallet integrations

4. Loyalty/rewards system implementation

5. Performance optimization for large user bases

I would appreciate suggestions from developers who have experience building SaaS platforms, membership systems, or similar applications.

What technologies, design patterns, or best practices would you recommend for creating a scalable digital membership platform?