DependencyWrapper.cs

public class DependencyWrapper : Wrapper
	{
		private readonly object dependency;

		public DependencyWrapper(Type behaviorType, object dependency) : base(behaviorType)
		{
			this.dependency = dependency;
		}

		protected override FubuMVC.Core.Registration.ObjectGraph.ObjectDef buildObjectDef()
		{
			var objectDef = base.buildObjectDef();
			objectDef.Child(dependency.GetType(), dependency);
			return objectDef;
		}
	}

Extension.cs

public static PoliciesExpression WrapBehaviorChainsWith<T, TV>(this PoliciesExpression policiesExpression, Func<ActionCall, TV> configurationAction) where T : IActionBehavior
		{
			policiesExpression.Add(new LambdaConfigurationAction(graph =>
			{
				graph.Actions().Each(call =>
				{
					call.AddAfter(new DependencyWrapper(typeof(T), configurationAction(call)));
				});
			}));

			return policiesExpression;
		}

Registration.cs

Policies
				.WrapBehaviorChainsWith<TransactionBehavior, TransactionSettings>(call =>
				{
					object[] transactionSettingsAttributes =
						call.Method.GetCustomAttributes(typeof (TransactionSettingsAttribute), true);
					if (transactionSettingsAttributes.Length == 1)
					{
						var useTransactionAttribute =
							(TransactionSettingsAttribute) transactionSettingsAttributes[0];
						return new TransactionSettings
						{
							Timeout = useTransactionAttribute.Timeout,
							IsolationLevel = useTransactionAttribute.IsolationLevel,
							Options = useTransactionAttribute.TransactionScopeOption
						};
					}
					return new TransactionSettings
					{
						Timeout = TimeSpan.FromSeconds(30),
						IsolationLevel = IsolationLevel.ReadCommitted,
						Options = TransactionScopeOption.Required
					};
				});