Ahmed worked on security hardening for API access within the calcom/cal.com repository, focusing on session management and access control. He addressed a vulnerability in the Add endpoint by implementing an early return for API requests lacking a valid user session, thereby preventing unauthorized data creation and exposure. This solution was developed using TypeScript and leveraged his skills in API development and session management. The change improved the handling of invalid sessions in the API request flow, reducing the attack surface and aligning with best practices for secure application design. Ahmed’s contribution was reviewed and merged as part of a collaborative security fix.