.NET 10 OpenAPI: Replace Swashbuckle with the Native Microsoft Package youtube.com

In this video, we explore the new first-party OpenAPI experience in .NET 10 and see why Microsoft.AspNetCore.OpenApi is becoming the preferred replacement for the old Swashbuckle-first setup, especially as ASP.NET Core continues pushing toward trimming and Native AOT scenarios.

We start with a simple Weather API example and wire up the new built-in OpenAPI support with Scalar for a clean interactive API reference. From there, we build a real sample with request and response models, add a second endpoint group, introduce API versioning, and organize everything so the documentation stays clear as the API grows.

After that, we move into the more advanced parts: generating the OpenAPI JSON automatically during build, customizing the document with descriptions, contact details, and licensing metadata, and then polishing the Scalar UI layout and settings for a more professional developer experience. .NET 10’s OpenAPI stack also brings stronger built-in support such as multiple OpenAPI documents, document transformers, and OpenAPI 3.1 generation, which makes it a very compelling option for modern ASP.NET Core APIs.

If you are building Minimal APIs or lightweight ASP.NET Core services and want a cleaner, faster, more future-friendly OpenAPI setup, this walkthrough will help you move away from the traditional Swagger template and adopt the new native approach with confidence.