Are you writing API clients by hand and updating them every time something changes? Are your API designs inconsistent across teams, with breaking changes only discovered in production? And are you relying on manual reviews and guidelines to keep everything under control, hoping that's enough?
It's not. And you're not alone.

In this session, you'll get an end-to-end look at how OpenAPI can fix all of that. We'll start with the basics: what OpenAPI is, how it works in .NET 11, and how to make the most of the latest features for both minimal APIs and controllers. From there, you'll learn that the true power of OpenAPI lies in the available tooling. Let's put your OpenAPI spec to work by generating production-ready API clients automatically with tools like NSwag, Kiota, and openapi-generator. No more manual updates. No more drift between your API and its clients.

But that's only part of the story. Most teams treat API definitions as "just documentation" and rely on reviews to keep things consistent. That doesn't scale. You'll learn how API linting with tools like Spectral, oasdiff, and Azure API Center can catch breaking changes early and turn guidelines into something that's actually enforced.

The following topics will be covered (with lots of demos!):

- OpenAPI in .NET 10: what's new and how to use it
- Generating production-ready API clients with NSwag, Kiota, and openapi-generator
- API linting and why it's the missing piece in most governance setups
- Enforcing API standards with Spectral and Azure API Center
- Catching breaking changes automatically with oasdiff

When time is left over, we'll also cover API Versioning in combination with OpenAPI!

By the end of this session, you'll have a clear picture of how to fix your API development lifecycle for good!

- This session is a combination of these 3 sessions:
- https://sessionize.com/s/sander-ten-brinke/api-governance-why-reviews-and-guidelines-arent-en/145828
- https://sessionize.com/s/sander-ten-brinke/the-best-ways-to-use-the-latest-openapi-features-i/102658
- https://sessionize.com/s/sander-ten-brinke/the-fastest-way-to-production-ready-api-clients/67208
- As a session, this needs at least 1.5 hours
- This session can be turned into a workshop!