Darrel is an Principal Program Manager at Microsoft responsible for Microsoft Graph developer tooling. He has been building distributed business applications on the Microsoft platform for more than 20 years. He is an active member of the .NET community and OSS contributor. He is a member of the OpenAPI Technical Steering Committee and a member of several Microsoft API review boards. He co-authored the O'Reilly book, Designing Evolvable Web APIs with ASP.NET.