diff --git a/ServiceScan.SourceGenerator.Tests/AddServicesTests.cs b/ServiceScan.SourceGenerator.Tests/AddServicesTests.cs
index 2c8e67b..af7aa1c 100644
--- a/ServiceScan.SourceGenerator.Tests/AddServicesTests.cs
+++ b/ServiceScan.SourceGenerator.Tests/AddServicesTests.cs
@@ -37,7 +37,7 @@ public class MyService2 : IService { }
                 .Add{lifetime}<global::GeneratorTests.IService, global::GeneratorTests.MyService1>()
                 .Add{lifetime}<global::GeneratorTests.IService, global::GeneratorTests.MyService2>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -56,7 +56,7 @@ public void AddServicesFromAnotherAssembly()
                 .AddTransient<global::External.IExternalService, global::External.ExternalService1>()
                 .AddTransient<global::External.IExternalService, global::External.ExternalService2>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -98,7 +98,7 @@ public class MyService2 : Core.IService { }
                 .AddScoped<global::Core.IService, global::Module1.MyService1>()
                 .AddScoped<global::Core.IService, global::Module2.MyService2>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -127,7 +127,7 @@ public class MyService2 : AbstractService { }
                 .AddTransient<global::GeneratorTests.IService, global::GeneratorTests.MyService1>()
                 .AddTransient<global::GeneratorTests.IService, global::GeneratorTests.MyService2>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -156,7 +156,7 @@ public class MyService2 : AbstractService { }
                 .AddTransient<global::GeneratorTests.BaseType, global::GeneratorTests.MyService1>()
                 .AddTransient<global::GeneratorTests.BaseType, global::GeneratorTests.MyService2>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -184,7 +184,7 @@ public class MyStringService : IService<string> { }
                 .AddTransient<global::GeneratorTests.IService<int>, global::GeneratorTests.MyIntService>()
                 .AddTransient<global::GeneratorTests.IService<string>, global::GeneratorTests.MyStringService>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -212,7 +212,7 @@ public class MyIntAndStringService : IService<int>, IService<string>, IOtherInte
                 .AddTransient<global::GeneratorTests.IService<int>, global::GeneratorTests.MyIntAndStringService>()
                 .AddTransient<global::GeneratorTests.IService<string>, global::GeneratorTests.MyIntAndStringService>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -240,7 +240,7 @@ public class MyIntAndStringService : IService<int>, IService<string> { }
                 .AddSingleton<global::GeneratorTests.IService<int>>(s => s.GetRequiredService<global::GeneratorTests.MyIntAndStringService>())
                 .AddSingleton<global::GeneratorTests.IService<string>>(s => s.GetRequiredService<global::GeneratorTests.MyIntAndStringService>());
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -267,7 +267,7 @@ public class MyStringService : IService<string> { }
             return services
                 .AddTransient<global::GeneratorTests.IService<int>, global::GeneratorTests.MyIntService>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -295,7 +295,7 @@ public class MyService2 : AbstractService { }
                 .AddTransient<global::GeneratorTests.AbstractService, global::GeneratorTests.MyService1>()
                 .AddTransient<global::GeneratorTests.AbstractService, global::GeneratorTests.MyService2>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -323,7 +323,7 @@ public class MyService2 : AbstractService { }
                 .AddTransient<global::GeneratorTests.MyService1, global::GeneratorTests.MyService1>()
                 .AddTransient<global::GeneratorTests.MyService2, global::GeneratorTests.MyService2>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -348,7 +348,7 @@ public class MyService { }
             return services
                 .AddTransient<global::GeneratorTests.MyService, global::GeneratorTests.MyService>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -376,7 +376,7 @@ public class MyStringService : AbstractService<string> { }
                 .AddTransient<global::GeneratorTests.AbstractService<int>, global::GeneratorTests.MyIntService>()
                 .AddTransient<global::GeneratorTests.AbstractService<string>, global::GeneratorTests.MyStringService>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -404,7 +404,7 @@ public class MyService2<T> : IGenericService<T> { }
                 .AddTransient(typeof(global::GeneratorTests.IGenericService<>), typeof(global::GeneratorTests.MyService1<>))
                 .AddTransient(typeof(global::GeneratorTests.IGenericService<>), typeof(global::GeneratorTests.MyService2<>));
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -432,7 +432,7 @@ public class MyService2<T> : IService { }
                 .AddTransient(typeof(global::GeneratorTests.IService), typeof(global::GeneratorTests.MyService1<>))
                 .AddTransient(typeof(global::GeneratorTests.IService), typeof(global::GeneratorTests.MyService2<>));
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -461,7 +461,7 @@ public class ServiceWithNonMatchingName {}
                 .AddTransient<global::GeneratorTests.MyFirstService, global::GeneratorTests.MyFirstService>()
                 .AddTransient<global::GeneratorTests.MySecondService, global::GeneratorTests.MySecondService>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -498,7 +498,7 @@ public class ServiceWithoutAttribute {}
                 .AddTransient<global::GeneratorTests.MyFirstService, global::GeneratorTests.MyFirstService>()
                 .AddTransient<global::GeneratorTests.MySecondService, global::GeneratorTests.MySecondService>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -533,7 +533,7 @@ public class ServiceWithNonMatchingName {}
             return services
                 .AddTransient<global::GeneratorTests.MyFirstService, global::GeneratorTests.MyFirstService>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -562,7 +562,7 @@ public class ServiceWithNonMatchingName {}
                 .AddTransient<global::GeneratorTests.MyFirstService, global::GeneratorTests.MyFirstService>()
                 .AddTransient<global::GeneratorTests.MySecondService, global::GeneratorTests.MySecondService>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -590,7 +590,7 @@ public class ThirdService {}
             .AddTransient<global::GeneratorTests.MyFirstService, global::GeneratorTests.MyFirstService>()
             .AddTransient<global::GeneratorTests.ThirdService, global::GeneratorTests.ThirdService>();
         """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -626,7 +626,7 @@ public class ThirdService {}
             .AddTransient<global::GeneratorTests.MyFirstService, global::GeneratorTests.MyFirstService>()
             .AddTransient<global::GeneratorTests.ThirdService, global::GeneratorTests.ThirdService>();
         """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -664,7 +664,7 @@ public class FourthService {}
             .AddTransient<global::GeneratorTests.MyFirstService, global::GeneratorTests.MyFirstService>()
             .AddTransient<global::GeneratorTests.FourthService, global::GeneratorTests.FourthService>();
         """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -696,7 +696,7 @@ public class ThirdService {}
             .AddTransient<global::GeneratorTests.MyFirstService, global::GeneratorTests.MyFirstService>()
             .AddTransient<global::GeneratorTests.ThirdService, global::GeneratorTests.ThirdService>();
         """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -728,7 +728,7 @@ public class ThirdService {}
             .AddTransient<global::GeneratorTests.MyFirstService, global::GeneratorTests.MyFirstService>()
             .AddTransient<global::GeneratorTests.ThirdService, global::GeneratorTests.ThirdService>();
         """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -762,7 +762,7 @@ public class FourthService {}
             .AddTransient<global::GeneratorTests.MyFirstService, global::GeneratorTests.MyFirstService>()
             .AddTransient<global::GeneratorTests.FourthService, global::GeneratorTests.FourthService>();
         """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -797,7 +797,7 @@ public class FourthService {}
             .AddTransient<global::GeneratorTests.ThirdService, global::GeneratorTests.ThirdService>()
             .AddTransient<global::GeneratorTests.FourthService, global::GeneratorTests.FourthService>();
         """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -828,7 +828,7 @@ public class MyThirdService : IService { }
                                  .AddTransient<global::GeneratorTests.IService, global::GeneratorTests.MyFirstService>()
                                  .AddTransient<global::GeneratorTests.IService, global::GeneratorTests.MyThirdService>();
                              """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -860,7 +860,7 @@ public class InterfacelessService {}
                 .AddTransient<global::GeneratorTests.IServiceB, global::GeneratorTests.MySecondService>()
                 .AddTransient<global::GeneratorTests.IServiceC, global::GeneratorTests.MySecondService>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -895,7 +895,7 @@ public class MyService: IServiceA, IServiceB {}
                 .AddSingleton<global::GeneratorTests.IServiceA>(s => s.GetRequiredService<global::GeneratorTests.MyService>())
                 .AddSingleton<global::GeneratorTests.IServiceB>(s => s.GetRequiredService<global::GeneratorTests.MyService>());
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -934,7 +934,7 @@ public void Dispose() {}
                 .AddTransient<global::GeneratorTests.IServiceB, global::GeneratorTests.MySecondService>()
                 .AddTransient<global::GeneratorTests.IServiceC, global::GeneratorTests.MySecondService>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -971,7 +971,7 @@ private class NestedPrivateService : IService { } // Shouldn't be added as non-a
                 .AddTransient<global::GeneratorTests.IService, global::GeneratorTests.ParentType1.MyService2>()
                 .AddTransient<global::GeneratorTests.IService, global::GeneratorTests.ParentType2.MyService1>();
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -1002,7 +1002,7 @@ public class MyService2 : IService { }
                 .AddKeyedTransient<global::GeneratorTests.IService, global::GeneratorTests.MyService1>(GetName<global::GeneratorTests.MyService1>())
                 .AddKeyedTransient<global::GeneratorTests.IService, global::GeneratorTests.MyService2>(GetName<global::GeneratorTests.MyService2>());
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -1033,7 +1033,7 @@ public class MyService2 : IService { }
                 .AddKeyedTransient<global::GeneratorTests.IService, global::GeneratorTests.MyService1>(GetName(typeof(global::GeneratorTests.MyService1)))
                 .AddKeyedTransient<global::GeneratorTests.IService, global::GeneratorTests.MyService2>(GetName(typeof(global::GeneratorTests.MyService2)));
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -1069,7 +1069,7 @@ public class MyService2 : IService
                 .AddKeyedTransient<global::GeneratorTests.IService, global::GeneratorTests.MyService1>(global::GeneratorTests.MyService1.Key)
                 .AddKeyedTransient<global::GeneratorTests.IService, global::GeneratorTests.MyService2>(global::GeneratorTests.MyService2.Key);
             """;
-        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[1].ToString());
+        Assert.Equal(Sources.GetMethodImplementation(registrations), results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -1084,8 +1084,8 @@ public void DontGenerateAnythingIfTypeIsInvalid()
             .RunGenerators(compilation)
             .GetRunResult();
 
-        // One file for generated attribute itself.
-        Assert.Single(results.GeneratedTrees);
+        // Two files: one for EmbeddedAttribute and one for generated attribute itself.
+        Assert.Equal(2, results.GeneratedTrees.Length);
     }
 
     private static Compilation CreateCompilation(params string[] source)
diff --git a/ServiceScan.SourceGenerator.Tests/CustomHandlerTests.cs b/ServiceScan.SourceGenerator.Tests/CustomHandlerTests.cs
index 3fb9e01..4b65b65 100644
--- a/ServiceScan.SourceGenerator.Tests/CustomHandlerTests.cs
+++ b/ServiceScan.SourceGenerator.Tests/CustomHandlerTests.cs
@@ -54,7 +54,7 @@ public static partial void ProcessServices()
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -102,7 +102,7 @@ public static partial void ProcessServices( string value, decimal number)
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -147,7 +147,7 @@ public static partial void ProcessServices()
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -201,7 +201,7 @@ public static partial class ServicesExtensions
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -259,7 +259,7 @@ public static partial IServiceCollection ProcessServices(this IServiceCollection
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -310,7 +310,7 @@ public static partial void ProcessServices()
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -360,7 +360,7 @@ public static partial void ProcessServices()
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -439,7 +439,7 @@ public static partial class ModelBuilderExtensions
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -487,7 +487,7 @@ public partial void ProcessServices()
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -538,7 +538,7 @@ public partial void ProcessServices()
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -592,7 +592,7 @@ public partial void ProcessServices()
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -645,7 +645,7 @@ public partial void ProcessServices( global::Microsoft.Extensions.DependencyInje
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -705,7 +705,7 @@ public static partial class ServiceCollectionExtensions
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -758,7 +758,7 @@ public static partial void ProcessServices()
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -803,7 +803,7 @@ public static partial void ProcessServices()
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -858,7 +858,7 @@ public static partial void AddHandlers()
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -914,7 +914,7 @@ public static partial void AddHandlers()
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -967,7 +967,7 @@ public static partial void AddProcessors()
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -1028,7 +1028,7 @@ public static partial void AddHandlers()
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -1079,7 +1079,7 @@ public static partial void ProcessServices()
                 }
             }
             """;
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     private static Compilation CreateCompilation(params string[] source)
diff --git a/ServiceScan.SourceGenerator.Tests/DiagnosticTests.cs b/ServiceScan.SourceGenerator.Tests/DiagnosticTests.cs
index f01284d..34ae7c0 100644
--- a/ServiceScan.SourceGenerator.Tests/DiagnosticTests.cs
+++ b/ServiceScan.SourceGenerator.Tests/DiagnosticTests.cs
@@ -171,7 +171,7 @@ public static partial class ServicesExtensions
                 }
             }
             """;
-        Assert.Equal(expectedFile, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expectedFile, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -211,7 +211,7 @@ public static partial void AddServices(this global::Microsoft.Extensions.Depende
                 }
             }
             """;
-        Assert.Equal(expectedFile, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expectedFile, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
diff --git a/ServiceScan.SourceGenerator.Tests/GeneratedMethodTests.cs b/ServiceScan.SourceGenerator.Tests/GeneratedMethodTests.cs
index 2acb602..c0132b3 100644
--- a/ServiceScan.SourceGenerator.Tests/GeneratedMethodTests.cs
+++ b/ServiceScan.SourceGenerator.Tests/GeneratedMethodTests.cs
@@ -57,7 +57,7 @@ namespace GeneratorTests;
             }
             """;
 
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -97,7 +97,7 @@ public static partial void AddServices(this IServiceCollection services)
             }
             """;
 
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -137,7 +137,7 @@ public static partial IServiceCollection AddServices( IServiceCollection service
             }
             """;
 
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -177,7 +177,7 @@ private partial void AddServices( IServiceCollection services)
             }
             """;
 
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -216,7 +216,7 @@ public static partial IServiceCollection AddServices(this IServiceCollection ser
             }
             """;
 
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     [Fact]
@@ -256,7 +256,7 @@ public static partial IServiceCollection AddServices(this IServiceCollection str
             }
             """;
 
-        Assert.Equal(expected, results.GeneratedTrees[1].ToString());
+        Assert.Equal(expected, results.GeneratedTrees[2].ToString());
     }
 
     private static Compilation CreateCompilation(params string[] source)
diff --git a/ServiceScan.SourceGenerator/DependencyInjectionGenerator.cs b/ServiceScan.SourceGenerator/DependencyInjectionGenerator.cs
index f2970f4..0ef50fc 100644
--- a/ServiceScan.SourceGenerator/DependencyInjectionGenerator.cs
+++ b/ServiceScan.SourceGenerator/DependencyInjectionGenerator.cs
@@ -15,6 +15,7 @@ public void Initialize(IncrementalGeneratorInitializationContext context)
     {
         context.RegisterPostInitializationOutput(context =>
         {
+            context.AddEmbeddedAttributeDefinition();
             context.AddSource("ServiceScanAttributes.Generated.cs", SourceText.From(GenerateAttributeInfo.Source, Encoding.UTF8));
         });
 
diff --git a/ServiceScan.SourceGenerator/Extensions/IncrementalGeneratorPostInitializationContextExtensions.cs b/ServiceScan.SourceGenerator/Extensions/IncrementalGeneratorPostInitializationContextExtensions.cs
new file mode 100644
index 0000000..d764b34
--- /dev/null
+++ b/ServiceScan.SourceGenerator/Extensions/IncrementalGeneratorPostInitializationContextExtensions.cs
@@ -0,0 +1,22 @@
+using System.Text;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.Text;
+
+namespace ServiceScan.SourceGenerator.Extensions;
+
+internal static class IncrementalGeneratorPostInitializationContextExtensions
+{
+    private const string EmbeddedAttributeSource = """
+        namespace Microsoft.CodeAnalysis
+        {
+            internal sealed partial class EmbeddedAttribute : global::System.Attribute
+            {
+            }
+        }
+        """;
+
+    public static void AddEmbeddedAttributeDefinition(this IncrementalGeneratorPostInitializationContext context)
+    {
+        context.AddSource("Microsoft.CodeAnalysis.EmbeddedAttribute", SourceText.From(EmbeddedAttributeSource, Encoding.UTF8));
+    }
+}
diff --git a/ServiceScan.SourceGenerator/GenerateAttributeInfo.cs b/ServiceScan.SourceGenerator/GenerateAttributeInfo.cs
index 9fef6b0..d2dfc5e 100644
--- a/ServiceScan.SourceGenerator/GenerateAttributeInfo.cs
+++ b/ServiceScan.SourceGenerator/GenerateAttributeInfo.cs
@@ -8,12 +8,12 @@ internal static class GenerateAttributeInfo
         #nullable enable
 
         using System;
-        using System.Diagnostics;
+        using Microsoft.CodeAnalysis;
         using Microsoft.Extensions.DependencyInjection;
 
         namespace ServiceScan.SourceGenerator;
 
-        [Conditional("CODE_ANALYSIS")]
+        [Embedded]
         [AttributeUsage(AttributeTargets.Method, AllowMultiple = true)]
         internal class GenerateServiceRegistrationsAttribute : Attribute
         {