Payment gateway with multi providers support

We are looking for an experienced C# .NET to build a payment gateway with multi providers support.

The first two payments are:
○ CreditCard
○ Paypal

• Microservices server architecture
• Net core (3.x or later)
• DDD-oriented microservice
• MySQL\Stored Procedures
• FluentValidation
• JSON
• Entity Framework\Dapper
• Swagger
• Unit tests
• Serilog
• MediatR