Expanding Payment Options and Enhancing Security for Pay4one Challenge: PayFor1 needed to expand its services and improve security.

Solution: Songpoem Labs:

Added new banks, payment channels, and networks. Implemented 3D Secure and OTP functionality. Refactored legacy code. Results:

Significantly increased transaction volume (targeting 8x growth). Technology: Elixir, Netsetter 3D Secure, Java SpringBoot

Timeline: 10 months

Challenges Overcome:

Navigated outdated code without documentation. Gained domain knowledge of card processing and various APIs. Implemented comprehensive error handling and retry mechanisms.