<PackageReference Include="NUnit" Version="3.0.0-alpha-5" />

FixtureBuilderAttribute

public abstract class FixtureBuilderAttribute : Attribute
The abstract base class for all NUnit attributes that build fixtures. The derived class should implement IFixtureBuilder. It is not implemented by this class to allow for future fixture-building interfaces.
using System; namespace NUnit.Framework { public abstract class FixtureBuilderAttribute : Attribute { public FixtureBuilderAttribute() { } } }