How can I write a test-mutation in F# using Ninja Turtles?

Question

How can I write a test-mutation in F# using Ninja Turtles?

Here's my test mutation (C#):

using NinjaTurtles;
using NUnit.Framework;

namespace Tests
{
    [TestFixture]
    public class _MutantTest
    {
        [Test, Category("Mutation"), MutationTest]
        public void Add_MutationTests()
        {
            MutationTestBuilder<SimpleCalculator>
                .For("Add")
                .Run();
        }
    }
}

Here's my unit test:

[TestFixture]
public class _Test
{
    [Test]
    public void Add()
    {
        Assert.AreEqual(5, SimpleCalculator.Add(2, 3));
    }
}

Here's my SUT:

public class SimpleCalculator
{
    public static int Add(int x, int y) => x + y;
}