In today’s agile software landscape, building robust and scalable applications hinges on well-defined APIs. The API design-first approach offers a structured methodology where the API contract is meticulously crafted before any code is written. This strategy is powered by the OpenAPI Specification (OAS) for Synchronous APIs and AsyncAPI Specification for Asynchronous APIs.
This article (an opinionanted tutorial) provides a practical guide to implementing API design-first in Synchronous .NET API projects, with a strong focus on its benefits for development, testing, and seamless integration into DevOps CI/CD pipelines. I will follow up with an AsyncAPI article later.