I am following this process to create a YAML build pipeline for a .NET Core Web API project:
When it comes to releasing it, I note that the (recently renamed) Azure DevOps doesn't seem to support YAML for defining release pipelines. However, I can see that deployment tasks have been defined eg:
Are we expecting an upgrade to the release pipelines functionality to support YAML and, if so, when?
Here is the new pipeline YAML file that gets created by default once you create a pipeline in Azure DevOps.
You can write the tasks you want your pipeline to perform or just run this script.