diff --git a/README.md b/README.md
index a601068..f0195f7 100644
--- a/README.md
+++ b/README.md
@@ -65,8 +65,10 @@ static partial class DataPortalExtensions {
 ## How to configure the generator
 
 You can configure the following for the generator to respect
-* method prefix
-* method suffix
+* method prefix (default = "")
+* method suffix (default = "")
+* Enable/Disable nullable annotation context (default = Enable)
+* SuppressWarningCS8669 (default = false)
 
 The fetch named method example from above can be resolved with a prefix/suffix to generate a method with the name `YourFetch` which in turn can be used and provides reliable compiler support.
 
@@ -75,6 +77,8 @@ You can add the following properties to your csproj-file to configure the genera
 <PropertyGroup>
     <DataPortalExtensionGen_MethodPrefix>Prefix</DataPortalExtensionGen_MethodPrefix>
     <DataPortalExtensionGen_MethodSuffix>Suffix</DataPortalExtensionGen_MethodSuffix>
+    <DataPortalExtensionGen_NullableContext>Enable/Disable</DataPortalExtensionGen_NullableContext>
+    <DataPortalExtensionGen_SuppressWarningCS8669>true/false</DataPortalExtensionGen_SuppressWarningCS8669>
 </PropertyGroup>
 ```
 
@@ -87,12 +91,6 @@ With this added the consuming project the generator picks the values up and adds
 - Special case commands to an extension like `commandPortal.ExecuteCommand(<params>)` which combines `Create`+`Execute`.
 - Support for generic business objects
 - Add attribute to exclude methods explicitly
-- Add proper NullableAnnotationContext settings
-- Add diagnostics
-    - Wrong usage/configuration
-        - Like extension class is not partial
-    - Wrong config setting (if possible)
-    - Detailed error when a private nested class is used for any csla method
 
 A lot of implementation details are derived/taken from the great series [Andrew Lock: Creating a source generator](https://andrewlock.net/series/creating-a-source-generator/). If you want to create your own source generator I can recommend that series wholeheartedly.
 
diff --git a/src/Csla.DataPortalExtensionGenerator/ConfigConstants.cs b/src/Csla.DataPortalExtensionGenerator/ConfigConstants.cs
new file mode 100644
index 0000000..eb65929
--- /dev/null
+++ b/src/Csla.DataPortalExtensionGenerator/ConfigConstants.cs
@@ -0,0 +1,8 @@
+namespace Ossendorf.Csla.DataPortalExtensionGenerator;
+
+internal static class ConfigConstants {
+    public const string MethodPrefix = "DataPortalExtensionGen_MethodPrefix";
+    public const string MethodSuffix = "DataPortalExtensionGen_MethodSuffix";
+    public const string NullableContext = "DataPortalExtensionGen_NullableContext";
+    public const string SuppressWarningCS8669 = "DataPortalExtensionGen_SuppressWarningCS8669";
+}
\ No newline at end of file
diff --git a/src/Csla.DataPortalExtensionGenerator/DataPortalExtensionGenerator.cs b/src/Csla.DataPortalExtensionGenerator/DataPortalExtensionGenerator.cs
index 698df37..1020761 100644
--- a/src/Csla.DataPortalExtensionGenerator/DataPortalExtensionGenerator.cs
+++ b/src/Csla.DataPortalExtensionGenerator/DataPortalExtensionGenerator.cs
@@ -2,6 +2,7 @@
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Text;
 using Ossendorf.Csla.DataPortalExtensionGenerator.Diagnostics;
+using System.Diagnostics.CodeAnalysis;
 using System.Text;
 
 namespace Ossendorf.Csla.DataPortalExtensionGenerator;
@@ -22,7 +23,10 @@ private static void AddMarkerAttribute(IncrementalGeneratorInitializationContext
         => context.RegisterPostInitializationOutput(ctx => ctx.AddSource("DataPortalExtensionsAttribute.g.cs", SourceText.From(GeneratorHelper.MarkerAttribute, Encoding.UTF8)));
 
     private static void AddCodeGenerator(IncrementalGeneratorInitializationContext context) {
-        var options = GetGeneratorOptions(context);
+        var optionsAndDiagnostics = GetGeneratorOptions(context);
+
+        var options = optionsAndDiagnostics
+            .Select((o, _) => o.Value);
 
         var extensionClassesAndDiagnostics = context.SyntaxProvider
             .ForAttributeWithMetadataName(
@@ -55,6 +59,10 @@ private static void AddCodeGenerator(IncrementalGeneratorInitializationContext c
             methodDeclarationsAndDiagnostics.SelectMany((m, _) => m.Errors),
             static (ctx, info) => ctx.ReportDiagnostic(info)
         );
+        context.RegisterSourceOutput(
+            optionsAndDiagnostics.SelectMany((o, _) => o.Errors),
+            static (ctx, info) => ctx.ReportDiagnostic(info)
+        );
 
         context.RegisterSourceOutput(
             source: classesToGenerateInto,
@@ -62,18 +70,38 @@ private static void AddCodeGenerator(IncrementalGeneratorInitializationContext c
         );
     }
 
-    private static IncrementalValueProvider<GeneratorOptions> GetGeneratorOptions(IncrementalGeneratorInitializationContext context) {
+    private static IncrementalValueProvider<Result<GeneratorOptions>> GetGeneratorOptions(IncrementalGeneratorInitializationContext context) {
         return context.AnalyzerConfigOptionsProvider.Select((options, _) => {
 
-            if (!options.GlobalOptions.TryGetValue("build_property.DataPortalExtensionGen_MethodPrefix", out var methodPrefix) || methodPrefix is null) {
+            if (!TryGetGlobalOption(ConfigConstants.MethodPrefix, out var methodPrefix) || methodPrefix is null) {
                 methodPrefix = "";
             }
 
-            if (!options.GlobalOptions.TryGetValue("build_property.DataPortalExtensionGen_MethodSuffix", out var methodSuffix) || methodSuffix is null) {
+            if (!TryGetGlobalOption(ConfigConstants.MethodSuffix, out var methodSuffix) || methodSuffix is null) {
                 methodSuffix = "";
             }
 
-            return new GeneratorOptions(methodPrefix, methodSuffix);
+            var errors = new List<DiagnosticInfo>();
+            var nullableContextOptions = NullableContextOptions.Enable;
+            if (TryGetGlobalOption(ConfigConstants.NullableContext, out var nullabilityContext)) {
+                if (nullabilityContext.Equals("Disable", StringComparison.OrdinalIgnoreCase)) {
+                    nullableContextOptions = NullableContextOptions.Disable;
+                } else if (!nullabilityContext.Equals("Enable", StringComparison.OrdinalIgnoreCase)) {
+                    errors.Add(NullableContextValueDiagnostic.Create(nullabilityContext));
+                }
+            }
+
+            var suppressWarningCS8669 = false;
+            if (TryGetGlobalOption(ConfigConstants.SuppressWarningCS8669, out var suppressWarningString)) {
+                if (!bool.TryParse(suppressWarningString, out suppressWarningCS8669)) {
+                    suppressWarningCS8669 = false;
+                    errors.Add(SuppressWarningCS8669ValueDiagnostic.Create(suppressWarningString));
+                }
+            }
+
+            return new Result<GeneratorOptions>(new GeneratorOptions(methodPrefix, methodSuffix, nullableContextOptions, suppressWarningCS8669), new EquatableArray<DiagnosticInfo>([.. errors]));
+
+            bool TryGetGlobalOption(string key, [NotNullWhen(true)] out string? value) => options.GlobalOptions.TryGetValue($"build_property.{key}", out value);
         });
     }
 }
\ No newline at end of file
diff --git a/src/Csla.DataPortalExtensionGenerator/Diagnostics/DiagnosticHelper.cs b/src/Csla.DataPortalExtensionGenerator/Diagnostics/DiagnosticHelper.cs
index 1244487..08f8088 100644
--- a/src/Csla.DataPortalExtensionGenerator/Diagnostics/DiagnosticHelper.cs
+++ b/src/Csla.DataPortalExtensionGenerator/Diagnostics/DiagnosticHelper.cs
@@ -5,6 +5,7 @@ namespace Ossendorf.Csla.DataPortalExtensionGenerator.Diagnostics;
 internal static class DiagnosticHelper {
     public static void ReportDiagnostic(this SourceProductionContext ctx, DiagnosticInfo info)
         => ctx.ReportDiagnostic(CreateDiagnostic(info));
+
     private static Diagnostic CreateDiagnostic(DiagnosticInfo info) {
         var diagnostic = Diagnostic.Create(info.Descriptor, info.Location);
         return diagnostic;
diff --git a/src/Csla.DataPortalExtensionGenerator/Diagnostics/DiagnosticId.cs b/src/Csla.DataPortalExtensionGenerator/Diagnostics/DiagnosticId.cs
new file mode 100644
index 0000000..1e5ca15
--- /dev/null
+++ b/src/Csla.DataPortalExtensionGenerator/Diagnostics/DiagnosticId.cs
@@ -0,0 +1,15 @@
+using NetEscapades.EnumGenerators;
+
+namespace Ossendorf.Csla.DataPortalExtensionGenerator.Diagnostics;
+
+[EnumExtensions]
+internal enum DiagnosticId {
+    // NotPartialDiagnostic
+    DPEGEN001,
+    // PrivateClassCanNotBeAParameterDiagnostic
+    DPEGEN002,
+    // NullableContextValueDiagnostic
+    DPEGEN003,
+    // SuppressWarningCS8669ValueDiagnostic
+    DPEGEN004,
+}
diff --git a/src/Csla.DataPortalExtensionGenerator/Diagnostics/DiagnosticInfo.cs b/src/Csla.DataPortalExtensionGenerator/Diagnostics/DiagnosticInfo.cs
index 24724f5..57e8804 100644
--- a/src/Csla.DataPortalExtensionGenerator/Diagnostics/DiagnosticInfo.cs
+++ b/src/Csla.DataPortalExtensionGenerator/Diagnostics/DiagnosticInfo.cs
@@ -2,4 +2,4 @@
 
 namespace Ossendorf.Csla.DataPortalExtensionGenerator.Diagnostics;
 
-internal record DiagnosticInfo(DiagnosticDescriptor Descriptor, Location Location);
\ No newline at end of file
+internal record DiagnosticInfo(DiagnosticDescriptor Descriptor, Location? Location);
\ No newline at end of file
diff --git a/src/Csla.DataPortalExtensionGenerator/Diagnostics/NotPartialDiagnostic.cs b/src/Csla.DataPortalExtensionGenerator/Diagnostics/NotPartialDiagnostic.cs
index 508b636..a55a175 100644
--- a/src/Csla.DataPortalExtensionGenerator/Diagnostics/NotPartialDiagnostic.cs
+++ b/src/Csla.DataPortalExtensionGenerator/Diagnostics/NotPartialDiagnostic.cs
@@ -3,10 +3,9 @@
 
 namespace Ossendorf.Csla.DataPortalExtensionGenerator.Diagnostics;
 internal static class NotPartialDiagnostic {
-    internal const string Id = "DPEGEN001";
     internal const string Message = $"The target of the {GeneratorHelper.MarkerAttributeNameWithSuffix} must be declared as partial.";
     internal const string Title = "Must be partial";
 
     public static DiagnosticInfo Create(ClassDeclarationSyntax syntax)
-        => new(new DiagnosticDescriptor(Id, Title, Message, "Usage", defaultSeverity: DiagnosticSeverity.Warning, isEnabledByDefault: true), syntax.GetLocation());
+        => new(new DiagnosticDescriptor(DiagnosticId.DPEGEN001.ToStringFast(), Title, Message, "Usage", defaultSeverity: DiagnosticSeverity.Warning, isEnabledByDefault: true), syntax.GetLocation());
 }
\ No newline at end of file
diff --git a/src/Csla.DataPortalExtensionGenerator/Diagnostics/NullableContextValueDiagnostic.cs b/src/Csla.DataPortalExtensionGenerator/Diagnostics/NullableContextValueDiagnostic.cs
new file mode 100644
index 0000000..554d97d
--- /dev/null
+++ b/src/Csla.DataPortalExtensionGenerator/Diagnostics/NullableContextValueDiagnostic.cs
@@ -0,0 +1,12 @@
+using Microsoft.CodeAnalysis;
+using System.Globalization;
+
+namespace Ossendorf.Csla.DataPortalExtensionGenerator.Diagnostics;
+
+internal static class NullableContextValueDiagnostic {
+    internal const string Message = $"The value '{{0}}' for setting '{ConfigConstants.NullableContext}' is not known. Only 'Enable' and 'Disable' are allowed. Default of 'Enable' is used.";
+    internal const string Title = "Nullable context value unknown";
+
+    public static DiagnosticInfo Create(string configValue)
+        => new(new DiagnosticDescriptor(DiagnosticId.DPEGEN003.ToStringFast(), Title, string.Format(CultureInfo.InvariantCulture, Message, configValue), "Usage", defaultSeverity: DiagnosticSeverity.Warning, isEnabledByDefault: true), null);
+}
diff --git a/src/Csla.DataPortalExtensionGenerator/Diagnostics/PrivateClassCanNotBeAParameterDiagnostic.cs b/src/Csla.DataPortalExtensionGenerator/Diagnostics/PrivateClassCanNotBeAParameterDiagnostic.cs
index 3a6c9e6..d81cfc6 100644
--- a/src/Csla.DataPortalExtensionGenerator/Diagnostics/PrivateClassCanNotBeAParameterDiagnostic.cs
+++ b/src/Csla.DataPortalExtensionGenerator/Diagnostics/PrivateClassCanNotBeAParameterDiagnostic.cs
@@ -5,10 +5,9 @@
 namespace Ossendorf.Csla.DataPortalExtensionGenerator.Diagnostics;
 
 internal static class PrivateClassCanNotBeAParameterDiagnostic {
-    internal const string Id = "DPEGEN002";
     internal const string Message = "The {0} method for {1} has a paramter of type {2} which is private and can't be used for generating an extension method.";
     internal const string Title = "CSLA method parameters must not be private types.";
 
     public static DiagnosticInfo Create(MethodDeclarationSyntax syntax, DataPortalMethod dataPortalMethod, string methodName, string invalidClassType)
-        => new(new DiagnosticDescriptor(Id, Title, string.Format(CultureInfo.InvariantCulture, Message, dataPortalMethod.ToStringFast(), methodName, invalidClassType), "Usage", defaultSeverity: DiagnosticSeverity.Error, isEnabledByDefault: true), syntax.GetLocation());
+        => new(new DiagnosticDescriptor(DiagnosticId.DPEGEN002.ToStringFast(), Title, string.Format(CultureInfo.InvariantCulture, Message, dataPortalMethod.ToStringFast(), methodName, invalidClassType), "Usage", defaultSeverity: DiagnosticSeverity.Error, isEnabledByDefault: true), syntax.GetLocation());
 }
\ No newline at end of file
diff --git a/src/Csla.DataPortalExtensionGenerator/Diagnostics/SuppressWarningCS8669ValueDiagnostic.cs b/src/Csla.DataPortalExtensionGenerator/Diagnostics/SuppressWarningCS8669ValueDiagnostic.cs
new file mode 100644
index 0000000..447789f
--- /dev/null
+++ b/src/Csla.DataPortalExtensionGenerator/Diagnostics/SuppressWarningCS8669ValueDiagnostic.cs
@@ -0,0 +1,12 @@
+using Microsoft.CodeAnalysis;
+using System.Globalization;
+
+namespace Ossendorf.Csla.DataPortalExtensionGenerator.Diagnostics;
+
+internal static class SuppressWarningCS8669ValueDiagnostic {
+    internal const string Message = $"The value '{{0}}' for setting '{ConfigConstants.SuppressWarningCS8669}' is not parseable to boolean. Default of false is used.";
+    internal const string Title = "CS8669 value unknown";
+
+    public static DiagnosticInfo Create(string configValue)
+        => new(new DiagnosticDescriptor(DiagnosticId.DPEGEN004.ToStringFast(), Title, string.Format(CultureInfo.InvariantCulture, Message, configValue), "Usage", defaultSeverity: DiagnosticSeverity.Warning, isEnabledByDefault: true), null);
+}
\ No newline at end of file
diff --git a/src/Csla.DataPortalExtensionGenerator/Emitter.cs b/src/Csla.DataPortalExtensionGenerator/Emitter.cs
index 73d78a0..3d2070c 100644
--- a/src/Csla.DataPortalExtensionGenerator/Emitter.cs
+++ b/src/Csla.DataPortalExtensionGenerator/Emitter.cs
@@ -22,21 +22,15 @@ public static void EmitExtensionClass(SourceProductionContext context, ((ClassFo
     }
 
     private static string GenerateCode(in ClassForExtensions extensionClass, in ImmutableArray<PortalOperationToGenerate> methods, in GeneratorOptions options, CancellationToken ct) {
-
-        var ns = extensionClass.Namespace;
-        var name = extensionClass.Name;
-
         return new StringBuilder()
             .AppendLine("// <auto-generated />")
-
-            //.AppendNullableContextDependingOnTarget(/*extensionClass.NullableAnnotation*/ NullableAnnotation.None)
-
+            .AppendNullableContext(in options)
             .AppendLine()
-            .AppendLine(string.IsNullOrWhiteSpace(ns) ? "" : $@"namespace {ns}")
+            .AppendNamespace(in extensionClass)
             .AppendLine("{")
             .Append("    [global::System.CodeDom.Compiler.GeneratedCode(\"Ossendorf.Csla.DataportalExtensionsGenerator\", \"").Append(GeneratorHelper.VersionString).AppendLine("\")]")
             .AppendLine("    [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = \"Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.\")]")
-            .AppendLine($"    static partial class {name}")
+            .AppendClassDeclaration(in extensionClass)
             .AppendLine("    {")
             .AppendMethodsGroupedByClass(in methods, in options, ct)
             .AppendLine("    }")
diff --git a/src/Csla.DataPortalExtensionGenerator/GeneratorHelper.cs b/src/Csla.DataPortalExtensionGenerator/GeneratorHelper.cs
index d0aebdf..6b13117 100644
--- a/src/Csla.DataPortalExtensionGenerator/GeneratorHelper.cs
+++ b/src/Csla.DataPortalExtensionGenerator/GeneratorHelper.cs
@@ -1,8 +1,4 @@
-using Microsoft.CodeAnalysis.CSharp.Syntax;
-using System.Collections.Immutable;
-using System.Text;
-
-namespace Ossendorf.Csla.DataPortalExtensionGenerator;
+namespace Ossendorf.Csla.DataPortalExtensionGenerator;
 internal static class GeneratorHelper {
 
     public const string FullyQalifiedNameOfMarkerAttribute = "Ossendorf.Csla.DataPortalExtensionGenerator.DataPortalExtensionsAttribute";
@@ -29,90 +25,6 @@ public class {MarkerAttributeNameWithSuffix} : global::System.Attribute {{
     }}
 }}";
 
-    public static StringBuilder AppendMethodsGroupedByClass(this StringBuilder sb, in ImmutableArray<PortalOperationToGenerate> foundOperations, in GeneratorOptions options, CancellationToken ct) {
-        const string intendation = "        ";
-
-        var groupedByClass = foundOperations.Cast<PortalOperationToGenerate>().GroupBy(o => o.Object).ToImmutableArray();
-
-        foreach (var operationsByClass in groupedByClass) {
-            ct.ThrowIfCancellationRequested();
-
-            if (!operationsByClass.Any()) {
-                continue;
-            }
-
-            var boName = operationsByClass.Key.GloballyQualifiedName;
-
-            foreach (var operation in operationsByClass) {
-                ct.ThrowIfCancellationRequested();
-
-                var childPrefix = IsChildMethod(operation.PortalMethod) ? "Child" : "";
-                string returnType;
-                if (operation.PortalMethod is DataPortalMethod.Delete) {
-                    returnType = "Task";
-                } else {
-                    returnType = $"Task<{boName}>";
-                }
-
-                var (parameters, arguments) = GetParametersAndArgumentsToUse(operation.Parameters, ct);
-
-                var visibilityModifier = operationsByClass.Key.HasPublicModifier && operation.Parameters.All(p => p.IsPublic) ? "public" : "internal";
-
-                _ = sb.Append(intendation)
-                    .Append(visibilityModifier).Append(" static ")
-                    .Append("global::System.Threading.Tasks.").Append(returnType).Append(" ").Append(options.MethodPrefix).Append(operation.MethodName).Append(options.MethodSuffix)
-                    .Append("(this global::Csla.I").Append(childPrefix).Append("DataPortal<").Append(boName).Append("> ")
-                    .Append("portal").Append(parameters).Append(")")
-                    .Append(" => portal.").Append(operation.PortalMethod.ToStringFast()).Append("Async")
-                    .Append("(").Append(arguments).Append(");").AppendLine();
-            }
-        }
-
-        return sb;
-
-        static bool IsChildMethod(DataPortalMethod portalMethod) {
-            return portalMethod switch {
-                DataPortalMethod.FetchChild or DataPortalMethod.CreateChild => true,
-                DataPortalMethod.Fetch or DataPortalMethod.Delete or DataPortalMethod.Create or DataPortalMethod.Execute => false,
-                _ => throw new InvalidOperationException($"Unknown dataportal method {portalMethod}"),
-            };
-        }
-    }
-
-    private static (StringBuilder Parameters, StringBuilder Arguments) GetParametersAndArgumentsToUse(EquatableArray<OperationParameter> parameters, CancellationToken ct) {
-        var parametersBuilder = new StringBuilder();
-        var argumentsBuilder = new StringBuilder();
-        if (parameters.Count == 0) {
-            return (parametersBuilder, argumentsBuilder);
-        }
-
-        foreach (var parameter in parameters) {
-            ct.ThrowIfCancellationRequested();
-
-            if (parametersBuilder.Length > 0) {
-                parametersBuilder.Append(", ");
-                argumentsBuilder.Append(", ");
-            }
-
-            parametersBuilder.Append(parameter.ParameterFormatted);
-            argumentsBuilder.Append(parameter.ArgumentFormatted);
-        }
-
-        if (parametersBuilder.Length > 0) {
-            parametersBuilder.Insert(0, ", ");
-        }
-
-        return (parametersBuilder, argumentsBuilder);
-    }
-
-    public static string ExtractAttributeName(NameSyntax? name) {
-        return name switch {
-            SimpleNameSyntax ins => ins.Identifier.Text,
-            QualifiedNameSyntax qns => qns.Right.Identifier.Text,
-            _ => ""
-        };
-    }
-
     private static readonly Dictionary<string, DataPortalMethod> _methodTranslations = [];
     static GeneratorHelper() {
         foreach (var portalMethod in Enum.GetValues(typeof(DataPortalMethod)).Cast<DataPortalMethod>()) {
diff --git a/src/Csla.DataPortalExtensionGenerator/GeneratorOptions.cs b/src/Csla.DataPortalExtensionGenerator/GeneratorOptions.cs
index 7556438..9a58a49 100644
--- a/src/Csla.DataPortalExtensionGenerator/GeneratorOptions.cs
+++ b/src/Csla.DataPortalExtensionGenerator/GeneratorOptions.cs
@@ -1,11 +1,17 @@
-namespace Ossendorf.Csla.DataPortalExtensionGenerator;
+using Microsoft.CodeAnalysis;
+
+namespace Ossendorf.Csla.DataPortalExtensionGenerator;
 
 internal readonly record struct GeneratorOptions {
     public readonly string MethodPrefix;
     public readonly string MethodSuffix;
+    public readonly NullableContextOptions NullableContextOptions;
+    public readonly bool SuppressWarningCS8669;
 
-    public GeneratorOptions(string methodPrefix, string methodSuffix) {
+    public GeneratorOptions(string methodPrefix, string methodSuffix, NullableContextOptions nullableContextOptions, bool suppressWarningCS8669) {
         MethodPrefix = methodPrefix;
         MethodSuffix = methodSuffix;
+        NullableContextOptions = nullableContextOptions;
+        SuppressWarningCS8669 = suppressWarningCS8669;
     }
 }
\ No newline at end of file
diff --git a/src/Csla.DataPortalExtensionGenerator/Ossendorf.Csla.DataPortalExtensionGenerator.props b/src/Csla.DataPortalExtensionGenerator/Ossendorf.Csla.DataPortalExtensionGenerator.props
index bfd2e66..f24309b 100644
--- a/src/Csla.DataPortalExtensionGenerator/Ossendorf.Csla.DataPortalExtensionGenerator.props
+++ b/src/Csla.DataPortalExtensionGenerator/Ossendorf.Csla.DataPortalExtensionGenerator.props
@@ -2,5 +2,7 @@
     <ItemGroup>
         <CompilerVisibleProperty Include="DataPortalExtensionGen_MethodPrefix" />
         <CompilerVisibleProperty Include="DataPortalExtensionGen_MethodSuffix" />
+        <CompilerVisibleProperty Include="DataPortalExtensionGen_NullableContext" />
+        <CompilerVisibleProperty Include="DataPortalExtensionGen_SuppressWarningCS8669" />
     </ItemGroup>
 </Project>
\ No newline at end of file
diff --git a/src/Csla.DataPortalExtensionGenerator/Parser.cs b/src/Csla.DataPortalExtensionGenerator/Parser.cs
index 9b601a0..0f3a96c 100644
--- a/src/Csla.DataPortalExtensionGenerator/Parser.cs
+++ b/src/Csla.DataPortalExtensionGenerator/Parser.cs
@@ -3,6 +3,7 @@
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Ossendorf.Csla.DataPortalExtensionGenerator.Diagnostics;
 using System.Diagnostics.CodeAnalysis;
+using System.Reflection.Metadata;
 using System.Text;
 
 namespace Ossendorf.Csla.DataPortalExtensionGenerator;
@@ -45,7 +46,7 @@ public static bool CouldBeCslaDataPortalAttribute(SyntaxNode node, CancellationT
             return false;
         }
 
-        var name = GeneratorHelper.ExtractAttributeName(attribute.Name);
+        var name = ExtractAttributeName(attribute.Name);
 
         return name is not null && GeneratorHelper.RecognizedCslaDataPortalAttributes.Keys.Contains(name);
     }
@@ -79,9 +80,8 @@ public static bool CouldBeCslaDataPortalAttribute(SyntaxNode node, CancellationT
         var parameters = GetRelevantParametersForMethod(methodDeclaration, ctx.SemanticModel, ct, dataPortalMethod, diagnostics);
         var errors = new EquatableArray<DiagnosticInfo>([.. diagnostics]);
 
-        var hasNullableEnabled = false;
         var methodName = methodDeclaration.Identifier.ToString();
-        return new Result<(PortalOperationToGenerate PortalOperationToGenerate, bool IsValid)>((new PortalOperationToGenerate(methodName, parameters, hasNullableEnabled, dataPortalMethod, portalObject.Value), true), errors);
+        return new Result<(PortalOperationToGenerate PortalOperationToGenerate, bool IsValid)>((new PortalOperationToGenerate(methodName, parameters, dataPortalMethod, portalObject.Value), true), errors);
     }
 
     private static bool GetPortalObject(SyntaxNode? classDeclarationNode, SemanticModel semanticModel, CancellationToken cancellationToken, [NotNullWhen(true)] out PortalObject? portalObject) {
@@ -121,8 +121,12 @@ private static EquatableArray<OperationParameter> GetRelevantParametersForMethod
                 continue;
             }
 
+            if (semanticModel.GetDeclaredSymbol(parameter, ct) is not IParameterSymbol parameterDeclaredSymbol) {
+                continue;
+            }
+
             var hasPublicModifier = HasPublicVisibility(parameterTypeSymbol, diagnostics, dataPortalMethod, methodSyntax);
-            var parametersFormattedForUsage = FormatForParameterUsage(parameter, parameterTypeSymbol);
+            var parametersFormattedForUsage = FormatForParameterUsage(parameter, parameterTypeSymbol, parameterDeclaredSymbol);
             foundParameters.Add(new OperationParameter(parameterTypeSymbol.ContainingNamespace?.ToString() ?? "", parameter.Identifier.ToString(), parametersFormattedForUsage, hasPublicModifier));
         }
 
@@ -134,7 +138,7 @@ static bool IsInjectedParameter(ParameterSyntax parameter) {
                 for (var j = 0; j < al.Attributes.Count; j++) {
                     var attr = al.Attributes[j];
 
-                    var attrName = EnsureAttributeSuffix(GeneratorHelper.ExtractAttributeName(attr.Name));
+                    var attrName = EnsureAttributeSuffix(ExtractAttributeName(attr.Name));
                     if (attrName.Equals("InjectAttribute", StringComparison.Ordinal)) {
                         return true;
                     }
@@ -169,8 +173,9 @@ static bool HasPublicVisibility(ITypeSymbol typeSymbol, List<DiagnosticInfo> dia
         }
     }
 
-    private static string FormatForParameterUsage(ParameterSyntax parameter, ITypeSymbol parameterTypeSymbol) {
+    private static string FormatForParameterUsage(ParameterSyntax parameter, ITypeSymbol parameterTypeSymbol, IParameterSymbol parameterDeclaredSymbol) {
         var typeString = parameterTypeSymbol.ToString();
+#pragma warning disable IDE0066 // Convert switch statement to expression, This is more readable than the switch-expression
         switch (typeString) {
             case "string":
             case "string[]":
@@ -217,65 +222,23 @@ private static string FormatForParameterUsage(ParameterSyntax parameter, ITypeSy
             case "object[]":
                 return parameter.ToString();
         }
+#pragma warning restore IDE0066 // Convert switch statement to expression
 
-        var typeStringBuilder = GetTypeString(parameterTypeSymbol);
-
-        var parameterVariableName = parameter.Identifier.ToString();
-        if (parameter.Default is not null) {
-            if (parameterTypeSymbol is { TypeKind: TypeKind.Enum } && parameter.Default.Value is MemberAccessExpressionSyntax valueOfEnum) {
-                parameterVariableName += $" = {typeStringBuilder}.{valueOfEnum.Name}";
-            } else {
-                parameterVariableName += $" {parameter.Default}";
-            }
-            //const int NullLiteralExpression = 8754; // See https://learn.microsoft.com/en-us/dotnet/api/microsoft.codeanalysis.csharp.syntaxkind?view=roslyn-dotnet-4.7.0#microsoft-codeanalysis-csharp-syntaxkind-nullliteralexpression
-            //if (parameter.Default is EqualsValueClauseSyntax { Value.RawKind: NullLiteralExpression }) {
-        }
-
-        return $"{typeStringBuilder} {parameterVariableName}";
-
-        static StringBuilder GetTypeString(ITypeSymbol typeSymbol, StringBuilder? sb = null) {
-            sb ??= new();
-
-            sb.Append("global::");
-            if (!typeSymbol.ContainingNamespace.IsGlobalNamespace) {
-                sb.Append(typeSymbol.ContainingNamespace).Append(".");
-            }
-
-            sb.Append(GetTypeWithHierarchy(typeSymbol));
-
-            if (typeSymbol is INamedTypeSymbol { TypeArguments.Length: > 0 } namedTypeSymbol) {
-                sb.Append("<");
-
-                for (var i = 0; i < namedTypeSymbol.TypeArguments.Length; i++) {
-                    if (i > 0) {
-                        sb.Append(", ");
-                    }
-
-                    sb = GetTypeString(namedTypeSymbol.TypeArguments[i], sb);
-                }
-
-                sb.Append(">");
-            }
-
-            return sb;
-
-            static StringBuilder GetTypeWithHierarchy(ITypeSymbol? typeSymbol, StringBuilder? sb = null) {
-                if (typeSymbol is null) {
-                    return sb ?? new();
-                }
-
-                sb ??= new();
-
-                if (sb.Length > 0) {
-                    sb.Insert(0, ".");
-                }
-
-                sb.Insert(0, typeSymbol.Name);
-
-                return GetTypeWithHierarchy(typeSymbol.ContainingType, sb);
-            }
-        }
+        return new StringBuilder()
+            .AppendType(parameterTypeSymbol, parameterDeclaredSymbol)
+            .Append(" ")
+            .AppendVariableName(parameter)
+            .AppendDefaultValue(parameter, parameterTypeSymbol, parameterDeclaredSymbol)
+            .ToString();
     }
 
     #endregion
+
+    private static string ExtractAttributeName(NameSyntax? name) {
+        return name switch {
+            SimpleNameSyntax ins => ins.Identifier.Text,
+            QualifiedNameSyntax qns => qns.Right.Identifier.Text,
+            _ => ""
+        };
+    }
 }
\ No newline at end of file
diff --git a/src/Csla.DataPortalExtensionGenerator/PortalOperationToGenerate.cs b/src/Csla.DataPortalExtensionGenerator/PortalOperationToGenerate.cs
index 3f3e69a..b6aa9ba 100644
--- a/src/Csla.DataPortalExtensionGenerator/PortalOperationToGenerate.cs
+++ b/src/Csla.DataPortalExtensionGenerator/PortalOperationToGenerate.cs
@@ -4,14 +4,12 @@ internal readonly record struct PortalOperationToGenerate {
 
     public readonly string MethodName;
     public readonly EquatableArray<OperationParameter> Parameters;
-    public readonly bool HasNullableEnabled;
     public readonly DataPortalMethod PortalMethod;
     public readonly PortalObject Object;
 
-    public PortalOperationToGenerate(string methodName, EquatableArray<OperationParameter> parameters, bool hasNullableEnabled, DataPortalMethod portalMethod, PortalObject @object) {
+    public PortalOperationToGenerate(string methodName, EquatableArray<OperationParameter> parameters, DataPortalMethod portalMethod, PortalObject @object) {
         MethodName = methodName;
         Parameters = parameters;
-        HasNullableEnabled = hasNullableEnabled;
         PortalMethod = portalMethod;
         Object = @object;
     }
diff --git a/src/Csla.DataPortalExtensionGenerator/StringBuilderExtensions.cs b/src/Csla.DataPortalExtensionGenerator/StringBuilderExtensions.cs
new file mode 100644
index 0000000..87610cc
--- /dev/null
+++ b/src/Csla.DataPortalExtensionGenerator/StringBuilderExtensions.cs
@@ -0,0 +1,131 @@
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp.Syntax;
+using System.Collections.Immutable;
+using System.Text;
+
+namespace Ossendorf.Csla.DataPortalExtensionGenerator;
+
+internal static class StringBuilderExtensions {
+    private static SymbolDisplayFormat FullyQualifiedFormat { get; } = SymbolDisplayFormat.FullyQualifiedFormat.WithMiscellaneousOptions(SymbolDisplayMiscellaneousOptions.IncludeNullableReferenceTypeModifier | SymbolDisplayMiscellaneousOptions.UseSpecialTypes);
+
+    public static StringBuilder AppendMethodsGroupedByClass(this StringBuilder sb, in ImmutableArray<PortalOperationToGenerate> foundOperations, in GeneratorOptions options, CancellationToken ct) {
+        const string intendation = "        ";
+
+        var groupedByClass = foundOperations.Cast<PortalOperationToGenerate>().GroupBy(o => o.Object).ToImmutableArray();
+
+        foreach (var operationsByClass in groupedByClass) {
+            ct.ThrowIfCancellationRequested();
+
+            if (!operationsByClass.Any()) {
+                continue;
+            }
+
+            var boName = operationsByClass.Key.GloballyQualifiedName;
+
+            foreach (var operation in operationsByClass) {
+                ct.ThrowIfCancellationRequested();
+
+                var childPrefix = IsChildMethod(operation.PortalMethod) ? "Child" : "";
+                string returnType;
+                if (operation.PortalMethod is DataPortalMethod.Delete) {
+                    returnType = "Task";
+                } else {
+                    returnType = $"Task<{boName}>";
+                }
+
+                var (parameters, arguments) = GetParametersAndArgumentsToUse(operation.Parameters, ct);
+
+                var visibilityModifier = operationsByClass.Key.HasPublicModifier && operation.Parameters.All(p => p.IsPublic) ? "public" : "internal";
+
+                _ = sb.Append(intendation)
+                    .Append(visibilityModifier).Append(" static ")
+                    .Append("global::System.Threading.Tasks.").Append(returnType).Append(" ").Append(options.MethodPrefix).Append(operation.MethodName).Append(options.MethodSuffix)
+                    .Append("(this global::Csla.I").Append(childPrefix).Append("DataPortal<").Append(boName).Append("> ")
+                    .Append("portal").Append(parameters).Append(")")
+                    .Append(" => portal.").Append(operation.PortalMethod.ToStringFast()).Append("Async")
+                    .Append("(").Append(arguments).Append(");").AppendLine();
+            }
+        }
+
+        return sb;
+
+        static bool IsChildMethod(DataPortalMethod portalMethod) {
+            return portalMethod switch {
+                DataPortalMethod.FetchChild or DataPortalMethod.CreateChild => true,
+                DataPortalMethod.Fetch or DataPortalMethod.Delete or DataPortalMethod.Create or DataPortalMethod.Execute => false,
+                _ => throw new InvalidOperationException($"Unknown dataportal method {portalMethod}"),
+            };
+        }
+    }
+
+    private static (StringBuilder Parameters, StringBuilder Arguments) GetParametersAndArgumentsToUse(EquatableArray<OperationParameter> parameters, CancellationToken ct) {
+        var parametersBuilder = new StringBuilder();
+        var argumentsBuilder = new StringBuilder();
+        if (parameters.Count == 0) {
+            return (parametersBuilder, argumentsBuilder);
+        }
+
+        foreach (var parameter in parameters) {
+            ct.ThrowIfCancellationRequested();
+
+            if (parametersBuilder.Length > 0) {
+                parametersBuilder.Append(", ");
+                argumentsBuilder.Append(", ");
+            }
+
+            parametersBuilder.Append(parameter.ParameterFormatted);
+            argumentsBuilder.Append(parameter.ArgumentFormatted);
+        }
+
+        if (parametersBuilder.Length > 0) {
+            parametersBuilder.Insert(0, ", ");
+        }
+
+        return (parametersBuilder, argumentsBuilder);
+    }
+
+    public static StringBuilder AppendNamespace(this StringBuilder sb, in ClassForExtensions classForExtensions)
+        => sb.AppendLine(string.IsNullOrWhiteSpace(classForExtensions.Namespace) ? "" : $@"namespace {classForExtensions.Namespace}");
+
+    public static StringBuilder AppendClassDeclaration(this StringBuilder sb, in ClassForExtensions classForExtensions)
+        => sb.AppendLine($"    static partial class {classForExtensions.Name}");
+
+    public static StringBuilder AppendNullableContext(this StringBuilder sb, in GeneratorOptions options) {
+        var directiveValue = options.NullableContextOptions.AnnotationsEnabled() ? "enable" : "disable";
+        sb.AppendLine($"#nullable {directiveValue}");
+        if (options.SuppressWarningCS8669) {
+            sb.AppendLine("#pragma warning disable CS8669 // The annotation for nullable reference types should only be used in code within a '#nullable' annotations context. Auto-generated code requires an explicit '#nullable' directive in source.");
+        }
+
+        return sb;
+    }
+
+    public static StringBuilder AppendType(this StringBuilder sb, ITypeSymbol typeSymbol, IParameterSymbol parameterDeclaredSymbol) {
+        sb.Append(typeSymbol.ToDisplayString(FullyQualifiedFormat));
+        if (parameterDeclaredSymbol.NullableAnnotation == NullableAnnotation.Annotated && !(sb[^1] == '?')) {
+            sb.Append("?");
+        }
+
+        return sb;
+    }
+
+    public static StringBuilder AppendVariableName(this StringBuilder sb, ParameterSyntax parameter) 
+        => sb.Append(parameter.Identifier.ToString());
+
+    public static StringBuilder AppendDefaultValue(this StringBuilder sb, ParameterSyntax parameter, ITypeSymbol parameterTypeSymbol, IParameterSymbol parameterDeclaredSymbol) {
+        if (parameter.Default is null) {
+            return sb;
+        }
+
+        if (parameterTypeSymbol is { TypeKind: TypeKind.Enum } && parameter.Default.Value is MemberAccessExpressionSyntax valueOfEnum) {
+            sb.Append(" = ").AppendType(parameterTypeSymbol, parameterDeclaredSymbol).Append(".").Append(valueOfEnum.Name);
+        } else {
+            sb.Append(" ").Append(parameter.Default);
+        }
+
+        return sb;
+
+        //const int NullLiteralExpression = 8754; // See https://learn.microsoft.com/en-us/dotnet/api/microsoft.codeanalysis.csharp.syntaxkind?view=roslyn-dotnet-4.7.0#microsoft-codeanalysis-csharp-syntaxkind-nullliteralexpression
+        //if (parameter.Default is EqualsValueClauseSyntax { Value.RawKind: NullLiteralExpression }) {
+    }
+}
\ No newline at end of file
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/DiagnosticTests.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/DiagnosticTests.cs
index 7c88167..e14fba4 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/DiagnosticTests.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/DiagnosticTests.cs
@@ -1,4 +1,7 @@
-namespace Ossendorf.Csla.DataPortalExtensionGenerator.Tests;
+using FluentAssertions;
+using Microsoft.CodeAnalysis;
+
+namespace Ossendorf.Csla.DataPortalExtensionGenerator.Tests;
 public class DiagnosticTests {
 
     private const string ValidExtensionClass = @$"
@@ -37,4 +40,63 @@ private class PrivateClass {{ }}
 
         TestHelper.Diagnostic(ValidExtensionClass, cslaClass, "DPEGEN002");
     }
-}
+
+    [Fact]
+    public void WhenUsingNullableAnnotationsInDisabledContextWithSuppressWarningsCS8632MustNotBeReported() {
+        const string cslaClass = $@"
+#nullable enable
+using Csla;
+
+namespace SomeCslaClass;
+
+public class Foo {{
+    [Fetch]
+    private void Bar(string? x, string? z = null){{ }}
+}}
+";
+        var globalCompilerOptions = TestAnalyzerConfigOptionsProvider.Create(new[] {
+            KeyValuePair.Create("DataPortalExtensionGen_SuppressWarningCS8669", bool.TrueString),
+            KeyValuePair.Create("DataPortalExtensionGen_NullableContext", "disable")
+        });
+
+        TestHelper.Diagnostic(ValidExtensionClass, cslaClass, globalCompilerOptions, diagnostics => diagnostics.Should().BeEmpty(), d => d.Should().BeEmpty(), NullableContextOptions.Disable);
+    }
+
+    [Fact]
+    public void WhenNullableContextConfigValueIsUnknownItMustGetDiagnosticDPEGEN003() {
+        const string cslaClass = $@"
+using Csla;
+
+namespace SomeCslaClass;
+
+public class Foo {{
+    [Fetch]
+    private void Bar(int a){{ }}
+}}
+";
+        var globalCompilerOptions = TestAnalyzerConfigOptionsProvider.Create(new[] {
+            KeyValuePair.Create("DataPortalExtensionGen_NullableContext", "Unknown")
+        });
+        
+        TestHelper.Diagnostic(ValidExtensionClass, cslaClass, "DPEGEN003", globalCompilerOptions);
+    }
+
+    [Fact]
+    public void WhenSuppressWarningCS8669ConfigValueIsUnknownItMustGetDiagnosticDPEGEN004() {
+        const string cslaClass = $@"
+using Csla;
+
+namespace SomeCslaClass;
+
+public class Foo {{
+    [Fetch]
+    private void Bar(int a){{ }}
+}}
+";
+        var globalCompilerOptions = TestAnalyzerConfigOptionsProvider.Create(new[] {
+            KeyValuePair.Create("DataPortalExtensionGen_SuppressWarningCS8669", "NotBooleanParseable")
+        });
+
+        TestHelper.Diagnostic(ValidExtensionClass, cslaClass, "DPEGEN004", globalCompilerOptions);
+    }
+}
\ No newline at end of file
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/GeneratorSnapshotTests.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/GeneratorSnapshotTests.cs
index 5b3f625..2534dae 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/GeneratorSnapshotTests.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/GeneratorSnapshotTests.cs
@@ -150,7 +150,7 @@ namespace MyTest.Greats;
 
 public class Foo {{
     public class Bar {{
-        public string Name {{ get; set; }}
+        public string Name {{ get; set; }} = """";
     }}
 }}
 ";
@@ -195,6 +195,24 @@ private void Bar({type}? krznbf) {{
         return TestHelper.Verify(cslaSource, t => t.UseParameters(type));
     }
 
+    [Theory]
+    [MemberData(nameof(CSharpBuiltInTypesNullable))]
+    public Task NullablePrimitivesArray(string type) {
+        var cslaSource = $@"
+using Csla;
+
+namespace VerifyTests;
+
+public class DummyBOWithParams {{
+    [Fetch]
+    private void Bar({type}[]? krznbf = null) {{
+    }}
+}}
+";
+
+        return TestHelper.Verify(cslaSource, t => t.UseParameters(type));
+    }
+
     [Fact]
     public Task GenericArity1Parameter() {
         var cslaSource = $@"
@@ -233,9 +251,9 @@ private void Bar(TestGenerica<RandomClass, RandomClass.RandomInner, RandomClass.
 namespace GenericTests;
 
 public class TestGenerica<T1,T2,T3> {{
-    public T1 Type1 {{ get; set; }}
-    public T2 Type2 {{ get; set; }}
-    public T3 Type3 {{ get; set; }}
+    public T1? Type1 {{ get; set; }}
+    public T2? Type2 {{ get; set; }}
+    public T3? Type3 {{ get; set; }}
 }}
 
 public class RandomClass {{
@@ -340,7 +358,7 @@ namespace VerifyTests;
 
 public class DummyBOWithParams {{
     [Fetch]
-    private void Bar(string a, int b = 1, List<string> list = null, string x = null, string z = """") {{
+    private void Bar(string a, int b = 1, List<string>? list = null, string? x = null, string z = """") {{
     }}
 }}
 ";
@@ -357,12 +375,12 @@ namespace VerifyTests;
 
 public class DummyBOWithParams {{
     [Fetch]
-    private void Bar(string a, int b = 1, int[] c = null, string x = null) {{
+    private void Bar(string a, int b = 1, int[]? c = null, string? x = null) {{
     }}
 }}
 ";
 
-        return TestHelper.Verify(cslaSource);
+        return TestHelper.Verify(cslaSource, true);
     }
 
     [Fact]
@@ -415,4 +433,40 @@ public static partial class DataPortalExtensions2 {{
 
         return TestHelper.Verify(cslaSource, additionalClassToGenerateInto, 3);
     }
+
+    [Fact]
+    public Task PrefixConfig() {
+        var cslaSource = $@"
+using Csla;
+
+namespace VerifyTests;
+
+public class DummyBOWithParams {{
+    [Fetch]
+    private void Bar(int krznbf) {{
+    }}
+}}
+";
+
+        var globalCompilerOptions = TestAnalyzerConfigOptionsProvider.Create("DataPortalExtensionGen_MethodPrefix", "Prefix");
+        return TestHelper.Verify(cslaSource, globalCompilerOptions);
+    }
+
+    [Fact]
+    public Task SuffixConfig() {
+        var cslaSource = $@"
+using Csla;
+
+namespace VerifyTests;
+
+public class DummyBOWithParams {{
+    [Fetch]
+    private void Bar(int krznbf) {{
+    }}
+}}
+";
+
+        var globalCompilerOptions = TestAnalyzerConfigOptionsProvider.Create("DataPortalExtensionGen_MethodSuffix", "Suffix");
+        return TestHelper.Verify(cslaSource, globalCompilerOptions);
+    }
 }
\ No newline at end of file
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArrayDefaultValue#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArrayDefaultValue#GeneratorTests.DataPortalExtensions.g.verified.cs
index 29fe51c..dc5ae5e 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArrayDefaultValue#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArrayDefaultValue#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,11 +1,12 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
     [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = "Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.")]
     static partial class DataPortalExtensions
     {
-        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, string a, int b = 1, int[] c = null, string x = null) => portal.FetchAsync(a, b, c, x);
+        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, string a, int b = 1, int[]? c = null, string? x = null) => portal.FetchAsync(a, b, c, x);
     }
 }
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=bool#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=bool#GeneratorTests.DataPortalExtensions.g.verified.cs
index f3a792b..f089d75 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=bool#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=bool#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=byte#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=byte#GeneratorTests.DataPortalExtensions.g.verified.cs
index c46c7f4..83eec11 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=byte#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=byte#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=char#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=char#GeneratorTests.DataPortalExtensions.g.verified.cs
index cd32847..41b90a8 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=char#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=char#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=decimal#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=decimal#GeneratorTests.DataPortalExtensions.g.verified.cs
index 38e3e09..0430994 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=decimal#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=decimal#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=double#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=double#GeneratorTests.DataPortalExtensions.g.verified.cs
index f083379..0f2e03b 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=double#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=double#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=float#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=float#GeneratorTests.DataPortalExtensions.g.verified.cs
index 6cb78bc..f841409 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=float#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=float#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=int#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=int#GeneratorTests.DataPortalExtensions.g.verified.cs
index 9ecff19..b4d8ea0 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=int#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=int#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=long#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=long#GeneratorTests.DataPortalExtensions.g.verified.cs
index c79d1d5..8fe1c40 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=long#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=long#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=object#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=object#GeneratorTests.DataPortalExtensions.g.verified.cs
index 1054d70..9e265ed 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=object#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=object#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=sbyte#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=sbyte#GeneratorTests.DataPortalExtensions.g.verified.cs
index 851e1c4..fd34060 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=sbyte#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=sbyte#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=short#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=short#GeneratorTests.DataPortalExtensions.g.verified.cs
index dd8a637..4601f21 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=short#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=short#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=string#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=string#GeneratorTests.DataPortalExtensions.g.verified.cs
index eee20b7..2254038 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=string#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=string#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=uint#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=uint#GeneratorTests.DataPortalExtensions.g.verified.cs
index a4a642c..628bac0 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=uint#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=uint#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=ulong#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=ulong#GeneratorTests.DataPortalExtensions.g.verified.cs
index 25703a6..a6206bf 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=ulong#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=ulong#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=ushort#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=ushort#GeneratorTests.DataPortalExtensions.g.verified.cs
index a5abe67..5cebef1 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=ushort#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.BuiltInTypeArray_type=ushort#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.DefaultValueParameter#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.DefaultValueParameter#GeneratorTests.DataPortalExtensions.g.verified.cs
index a4bbe63..4b87a91 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.DefaultValueParameter#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.DefaultValueParameter#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=Create#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=Create#GeneratorTests.DataPortalExtensions.g.verified.cs
index 072942d..825b6cd 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=Create#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=Create#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=CreateAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=CreateAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs
index 072942d..825b6cd 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=CreateAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=CreateAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=CreateChild#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=CreateChild#GeneratorTests.DataPortalExtensions.g.verified.cs
index 13f0ffb..36bad0c 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=CreateChild#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=CreateChild#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=CreateChildAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=CreateChildAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs
index 13f0ffb..36bad0c 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=CreateChildAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=CreateChildAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=Delete#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=Delete#GeneratorTests.DataPortalExtensions.g.verified.cs
index 4daa506..a9bed8f 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=Delete#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=Delete#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=DeleteAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=DeleteAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs
index 4daa506..a9bed8f 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=DeleteAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=DeleteAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=Execute#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=Execute#GeneratorTests.DataPortalExtensions.g.verified.cs
index 497fbd6..02a755f 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=Execute#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=Execute#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=ExecuteAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=ExecuteAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs
index 497fbd6..02a755f 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=ExecuteAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=ExecuteAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=Fetch#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=Fetch#GeneratorTests.DataPortalExtensions.g.verified.cs
index ef74c94..1767fdd 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=Fetch#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=Fetch#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=FetchAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=FetchAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs
index ef74c94..1767fdd 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=FetchAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=FetchAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=FetchChild#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=FetchChild#GeneratorTests.DataPortalExtensions.g.verified.cs
index fd7b9e0..2dd3c41 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=FetchChild#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=FetchChild#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=FetchChildAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=FetchChildAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs
index fd7b9e0..2dd3c41 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=FetchChildAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EmptyParameters_portalMethod=FetchChildAttribute#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EnumParameter#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EnumParameter#GeneratorTests.DataPortalExtensions.g.verified.cs
index 9c1cc94..8b3e952 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EnumParameter#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EnumParameter#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EnumParameterDefaultValue#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EnumParameterDefaultValue#GeneratorTests.DataPortalExtensions.g.verified.cs
index 5aeb605..43bf982 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EnumParameterDefaultValue#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.EnumParameterDefaultValue#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.GenericArity1Parameter#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.GenericArity1Parameter#GeneratorTests.DataPortalExtensions.g.verified.cs
index a6d2a2b..b008bd0 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.GenericArity1Parameter#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.GenericArity1Parameter#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.GenericArity3Parameter#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.GenericArity3Parameter#GeneratorTests.DataPortalExtensions.g.verified.cs
index 3368754..f1fe48d 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.GenericArity3Parameter#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.GenericArity3Parameter#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.GenericParameterDefaultValue#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.GenericParameterDefaultValue#GeneratorTests.DataPortalExtensions.g.verified.cs
index 3de4c20..52042a7 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.GenericParameterDefaultValue#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.GenericParameterDefaultValue#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,11 +1,12 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
     [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = "Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.")]
     static partial class DataPortalExtensions
     {
-        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, string a, int b = 1, global::System.Collections.Generic.List<global::System.String> list = null, string x = null, string z = "") => portal.FetchAsync(a, b, list, x, z);
+        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, string a, int b = 1, global::System.Collections.Generic.List<string>? list = null, string? x = null, string z = "") => portal.FetchAsync(a, b, list, x, z);
     }
 }
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.InjectedParametersIgnored#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.InjectedParametersIgnored#GeneratorTests.DataPortalExtensions.g.verified.cs
index 260f209..bc74d9d 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.InjectedParametersIgnored#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.InjectedParametersIgnored#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.InternalParameterMustMakeTheExtensionInternal#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.InternalParameterMustMakeTheExtensionInternal#GeneratorTests.DataPortalExtensions.g.verified.cs
index 35bce48..f4d41cf 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.InternalParameterMustMakeTheExtensionInternal#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.InternalParameterMustMakeTheExtensionInternal#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.MultiplePrimitiveParameters#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.MultiplePrimitiveParameters#GeneratorTests.DataPortalExtensions.g.verified.cs
index cce0daa..4986153 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.MultiplePrimitiveParameters#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.MultiplePrimitiveParameters#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NestedTypeAsBusinessObjectType#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NestedTypeAsBusinessObjectType#GeneratorTests.DataPortalExtensions.g.verified.cs
index d057e5a..0d9d20d 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NestedTypeAsBusinessObjectType#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NestedTypeAsBusinessObjectType#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NestedTypeAsParameter#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NestedTypeAsParameter#GeneratorTests.DataPortalExtensions.g.verified.cs
index 08fd6ee..4f273ed 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NestedTypeAsParameter#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NestedTypeAsParameter#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullableEnum#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullableEnum#GeneratorTests.DataPortalExtensions.g.verified.cs
index cbaede2..1ddd012 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullableEnum#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullableEnum#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,11 +1,12 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
     [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = "Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.")]
     static partial class DataPortalExtensions
     {
-        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, global::System.Nullable<global::TestEnum.SomeEnum> krznbf) => portal.FetchAsync(krznbf);
+        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, global::TestEnum.SomeEnum? krznbf) => portal.FetchAsync(krznbf);
     }
 }
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=bool#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=bool#GeneratorTests.DataPortalExtensions.g.verified.cs
new file mode 100644
index 0000000..a376da7
--- /dev/null
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=bool#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -0,0 +1,12 @@
+//HintName: GeneratorTests.DataPortalExtensions.g.cs
+// <auto-generated />
+#nullable enable
+
+namespace GeneratorTests
+{
+    [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = "Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.")]
+    static partial class DataPortalExtensions
+    {
+        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, bool[]? krznbf = null) => portal.FetchAsync(krznbf);
+    }
+}
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=byte#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=byte#GeneratorTests.DataPortalExtensions.g.verified.cs
new file mode 100644
index 0000000..ff9154f
--- /dev/null
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=byte#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -0,0 +1,12 @@
+//HintName: GeneratorTests.DataPortalExtensions.g.cs
+// <auto-generated />
+#nullable enable
+
+namespace GeneratorTests
+{
+    [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = "Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.")]
+    static partial class DataPortalExtensions
+    {
+        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, byte[]? krznbf = null) => portal.FetchAsync(krznbf);
+    }
+}
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=char#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=char#GeneratorTests.DataPortalExtensions.g.verified.cs
new file mode 100644
index 0000000..991ab1a
--- /dev/null
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=char#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -0,0 +1,12 @@
+//HintName: GeneratorTests.DataPortalExtensions.g.cs
+// <auto-generated />
+#nullable enable
+
+namespace GeneratorTests
+{
+    [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = "Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.")]
+    static partial class DataPortalExtensions
+    {
+        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, char[]? krznbf = null) => portal.FetchAsync(krznbf);
+    }
+}
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=decimal#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=decimal#GeneratorTests.DataPortalExtensions.g.verified.cs
new file mode 100644
index 0000000..fde7c0d
--- /dev/null
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=decimal#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -0,0 +1,12 @@
+//HintName: GeneratorTests.DataPortalExtensions.g.cs
+// <auto-generated />
+#nullable enable
+
+namespace GeneratorTests
+{
+    [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = "Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.")]
+    static partial class DataPortalExtensions
+    {
+        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, decimal[]? krznbf = null) => portal.FetchAsync(krznbf);
+    }
+}
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=double#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=double#GeneratorTests.DataPortalExtensions.g.verified.cs
new file mode 100644
index 0000000..4467f99
--- /dev/null
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=double#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -0,0 +1,12 @@
+//HintName: GeneratorTests.DataPortalExtensions.g.cs
+// <auto-generated />
+#nullable enable
+
+namespace GeneratorTests
+{
+    [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = "Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.")]
+    static partial class DataPortalExtensions
+    {
+        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, double[]? krznbf = null) => portal.FetchAsync(krznbf);
+    }
+}
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=float#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=float#GeneratorTests.DataPortalExtensions.g.verified.cs
new file mode 100644
index 0000000..315ce7d
--- /dev/null
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=float#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -0,0 +1,12 @@
+//HintName: GeneratorTests.DataPortalExtensions.g.cs
+// <auto-generated />
+#nullable enable
+
+namespace GeneratorTests
+{
+    [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = "Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.")]
+    static partial class DataPortalExtensions
+    {
+        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, float[]? krznbf = null) => portal.FetchAsync(krznbf);
+    }
+}
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=int#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=int#GeneratorTests.DataPortalExtensions.g.verified.cs
new file mode 100644
index 0000000..fe869a3
--- /dev/null
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=int#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -0,0 +1,12 @@
+//HintName: GeneratorTests.DataPortalExtensions.g.cs
+// <auto-generated />
+#nullable enable
+
+namespace GeneratorTests
+{
+    [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = "Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.")]
+    static partial class DataPortalExtensions
+    {
+        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, int[]? krznbf = null) => portal.FetchAsync(krznbf);
+    }
+}
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=long#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=long#GeneratorTests.DataPortalExtensions.g.verified.cs
new file mode 100644
index 0000000..8ba225c
--- /dev/null
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=long#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -0,0 +1,12 @@
+//HintName: GeneratorTests.DataPortalExtensions.g.cs
+// <auto-generated />
+#nullable enable
+
+namespace GeneratorTests
+{
+    [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = "Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.")]
+    static partial class DataPortalExtensions
+    {
+        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, long[]? krznbf = null) => portal.FetchAsync(krznbf);
+    }
+}
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=sbyte#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=sbyte#GeneratorTests.DataPortalExtensions.g.verified.cs
new file mode 100644
index 0000000..a939123
--- /dev/null
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=sbyte#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -0,0 +1,12 @@
+//HintName: GeneratorTests.DataPortalExtensions.g.cs
+// <auto-generated />
+#nullable enable
+
+namespace GeneratorTests
+{
+    [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = "Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.")]
+    static partial class DataPortalExtensions
+    {
+        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, sbyte[]? krznbf = null) => portal.FetchAsync(krznbf);
+    }
+}
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=short#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=short#GeneratorTests.DataPortalExtensions.g.verified.cs
new file mode 100644
index 0000000..b7ccabe
--- /dev/null
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=short#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -0,0 +1,12 @@
+//HintName: GeneratorTests.DataPortalExtensions.g.cs
+// <auto-generated />
+#nullable enable
+
+namespace GeneratorTests
+{
+    [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = "Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.")]
+    static partial class DataPortalExtensions
+    {
+        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, short[]? krznbf = null) => portal.FetchAsync(krznbf);
+    }
+}
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=uint#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=uint#GeneratorTests.DataPortalExtensions.g.verified.cs
new file mode 100644
index 0000000..8529043
--- /dev/null
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=uint#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -0,0 +1,12 @@
+//HintName: GeneratorTests.DataPortalExtensions.g.cs
+// <auto-generated />
+#nullable enable
+
+namespace GeneratorTests
+{
+    [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = "Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.")]
+    static partial class DataPortalExtensions
+    {
+        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, uint[]? krznbf = null) => portal.FetchAsync(krznbf);
+    }
+}
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=ulong#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=ulong#GeneratorTests.DataPortalExtensions.g.verified.cs
new file mode 100644
index 0000000..9d80d60
--- /dev/null
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=ulong#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -0,0 +1,12 @@
+//HintName: GeneratorTests.DataPortalExtensions.g.cs
+// <auto-generated />
+#nullable enable
+
+namespace GeneratorTests
+{
+    [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = "Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.")]
+    static partial class DataPortalExtensions
+    {
+        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, ulong[]? krznbf = null) => portal.FetchAsync(krznbf);
+    }
+}
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=ushort#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=ushort#GeneratorTests.DataPortalExtensions.g.verified.cs
new file mode 100644
index 0000000..df285cc
--- /dev/null
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitivesArray_type=ushort#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -0,0 +1,12 @@
+//HintName: GeneratorTests.DataPortalExtensions.g.cs
+// <auto-generated />
+#nullable enable
+
+namespace GeneratorTests
+{
+    [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = "Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.")]
+    static partial class DataPortalExtensions
+    {
+        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> Bar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, ushort[]? krznbf = null) => portal.FetchAsync(krznbf);
+    }
+}
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=bool#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=bool#GeneratorTests.DataPortalExtensions.g.verified.cs
index 2275377..6c1d6e8 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=bool#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=bool#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=byte#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=byte#GeneratorTests.DataPortalExtensions.g.verified.cs
index ecf4ba2..9b13e41 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=byte#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=byte#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=char#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=char#GeneratorTests.DataPortalExtensions.g.verified.cs
index 696f10a..34b9646 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=char#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=char#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=decimal#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=decimal#GeneratorTests.DataPortalExtensions.g.verified.cs
index 3d87124..b4b3647 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=decimal#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=decimal#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=double#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=double#GeneratorTests.DataPortalExtensions.g.verified.cs
index fbb63a4..839049f 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=double#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=double#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=float#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=float#GeneratorTests.DataPortalExtensions.g.verified.cs
index ef774ad..51122cc 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=float#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=float#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=int#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=int#GeneratorTests.DataPortalExtensions.g.verified.cs
index 6f864f0..66611cb 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=int#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=int#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=long#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=long#GeneratorTests.DataPortalExtensions.g.verified.cs
index 922f4c3..d06646b 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=long#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=long#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=sbyte#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=sbyte#GeneratorTests.DataPortalExtensions.g.verified.cs
index 5f56fec..eb883cf 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=sbyte#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=sbyte#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=short#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=short#GeneratorTests.DataPortalExtensions.g.verified.cs
index c2d0b89..e5d7df9 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=short#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=short#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=uint#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=uint#GeneratorTests.DataPortalExtensions.g.verified.cs
index 10eb416..05cece7 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=uint#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=uint#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=ulong#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=ulong#GeneratorTests.DataPortalExtensions.g.verified.cs
index f99a6d0..6d36dfd 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=ulong#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=ulong#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=ushort#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=ushort#GeneratorTests.DataPortalExtensions.g.verified.cs
index f7ccdde..0531bef 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=ushort#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.NullablePrimitves_type=ushort#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.OnlyInjectedParameters#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.OnlyInjectedParameters#GeneratorTests.DataPortalExtensions.g.verified.cs
index 7ed6711..97aae3b 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.OnlyInjectedParameters#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.OnlyInjectedParameters#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.PrefixConfig#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.PrefixConfig#GeneratorTests.DataPortalExtensions.g.verified.cs
new file mode 100644
index 0000000..fbcff9f
--- /dev/null
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.PrefixConfig#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -0,0 +1,12 @@
+//HintName: GeneratorTests.DataPortalExtensions.g.cs
+// <auto-generated />
+#nullable enable
+
+namespace GeneratorTests
+{
+    [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = "Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.")]
+    static partial class DataPortalExtensions
+    {
+        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> PrefixBar(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, int krznbf) => portal.FetchAsync(krznbf);
+    }
+}
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.SuffixConfig#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.SuffixConfig#GeneratorTests.DataPortalExtensions.g.verified.cs
new file mode 100644
index 0000000..6935298
--- /dev/null
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.SuffixConfig#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -0,0 +1,12 @@
+//HintName: GeneratorTests.DataPortalExtensions.g.cs
+// <auto-generated />
+#nullable enable
+
+namespace GeneratorTests
+{
+    [global::System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage(Justification = "Generated by the Ossendorf.Csla.DataPortalExtensionsGenerators source generator.")]
+    static partial class DataPortalExtensions
+    {
+        public static global::System.Threading.Tasks.Task<global::VerifyTests.DummyBOWithParams> BarSuffix(this global::Csla.IDataPortal<global::VerifyTests.DummyBOWithParams> portal, int krznbf) => portal.FetchAsync(krznbf);
+    }
+}
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.TwoClassesToGenerateInto#GeneratorTests.DataPortalExtensions.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.TwoClassesToGenerateInto#GeneratorTests.DataPortalExtensions.g.verified.cs
index 63d1eb2..9f9518b 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.TwoClassesToGenerateInto#GeneratorTests.DataPortalExtensions.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.TwoClassesToGenerateInto#GeneratorTests.DataPortalExtensions.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests.DataPortalExtensions.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.TwoClassesToGenerateInto#GeneratorTests2.DataPortalExtensions2.g.verified.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.TwoClassesToGenerateInto#GeneratorTests2.DataPortalExtensions2.g.verified.cs
index 4d5ea26..f9e1ec3 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.TwoClassesToGenerateInto#GeneratorTests2.DataPortalExtensions2.g.verified.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/Snapshots/GeneratorSnapshotTests.TwoClassesToGenerateInto#GeneratorTests2.DataPortalExtensions2.g.verified.cs
@@ -1,5 +1,6 @@
 //HintName: GeneratorTests2.DataPortalExtensions2.g.cs
 // <auto-generated />
+#nullable enable
 
 namespace GeneratorTests2
 {
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/TestAnalyzerConfigOptions.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/TestAnalyzerConfigOptions.cs
new file mode 100644
index 0000000..041df45
--- /dev/null
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/TestAnalyzerConfigOptions.cs
@@ -0,0 +1,21 @@
+using Microsoft.CodeAnalysis.Diagnostics;
+using System.Collections.Immutable;
+using System.Diagnostics.CodeAnalysis;
+
+namespace Ossendorf.Csla.DataPortalExtensionGenerator.Tests;
+
+internal sealed class TestAnalyzerConfigOptions : AnalyzerConfigOptions {
+    internal static readonly ImmutableDictionary<string, string> EmptyDictionary = ImmutableDictionary.Create<string, string>(KeyComparer);
+
+    public static TestAnalyzerConfigOptions Empty { get; } = new TestAnalyzerConfigOptions(EmptyDictionary);
+
+    private readonly ImmutableDictionary<string, string> _options;
+
+    public TestAnalyzerConfigOptions(ImmutableDictionary<string, string> options) {
+        _options = options;
+    }
+
+    public override bool TryGetValue(string key, [NotNullWhen(true)] out string? value) => _options.TryGetValue(key[15..], out value);
+
+    public override IEnumerable<string> Keys => _options.Keys;
+}
\ No newline at end of file
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/TestAnalyzerConfigOptionsProvider.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/TestAnalyzerConfigOptionsProvider.cs
new file mode 100644
index 0000000..a444739
--- /dev/null
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/TestAnalyzerConfigOptionsProvider.cs
@@ -0,0 +1,28 @@
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.Diagnostics;
+using System.Collections.Immutable;
+
+namespace Ossendorf.Csla.DataPortalExtensionGenerator.Tests;
+
+internal sealed class TestAnalyzerConfigOptionsProvider : AnalyzerConfigOptionsProvider {
+
+    public static TestAnalyzerConfigOptionsProvider Empty { get; } = new TestAnalyzerConfigOptionsProvider(TestAnalyzerConfigOptions.Empty);
+
+    private readonly ImmutableDictionary<object, AnalyzerConfigOptions> _treeDict = ImmutableDictionary<object, AnalyzerConfigOptions>.Empty;
+
+    public override AnalyzerConfigOptions GlobalOptions { get; }
+
+    private TestAnalyzerConfigOptionsProvider(AnalyzerConfigOptions globalOptions) {
+        GlobalOptions = globalOptions;
+    }
+
+    public override AnalyzerConfigOptions GetOptions(SyntaxTree tree) 
+        => TestAnalyzerConfigOptions.Empty;
+    public override AnalyzerConfigOptions GetOptions(AdditionalText textFile) 
+        => TestAnalyzerConfigOptions.Empty;
+
+    public static TestAnalyzerConfigOptionsProvider Create(string key, string value) => Create(new[] { KeyValuePair.Create(key, value) });
+
+    public static TestAnalyzerConfigOptionsProvider Create(IEnumerable<KeyValuePair<string,string>> config) => new(new TestAnalyzerConfigOptions(ImmutableDictionary.CreateRange(config))
+);
+}
diff --git a/tests/Csla.DataPortalExtensionGenerator.Tests/TestHelper.cs b/tests/Csla.DataPortalExtensionGenerator.Tests/TestHelper.cs
index b042183..73a3b28 100644
--- a/tests/Csla.DataPortalExtensionGenerator.Tests/TestHelper.cs
+++ b/tests/Csla.DataPortalExtensionGenerator.Tests/TestHelper.cs
@@ -1,7 +1,10 @@
 using Csla;
 using FluentAssertions;
+using FluentAssertions.Execution;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.CSharp;
+using Microsoft.CodeAnalysis.Diagnostics;
+using System.Collections.Immutable;
 
 namespace Ossendorf.Csla.DataPortalExtensionGenerator.Tests;
 
@@ -14,15 +17,23 @@ public static partial class DataPortalExtensions {{
     }}
 }}";
 
-    public static Task Verify(string cslaSource) => Verify(cslaSource, "");
+    public static Task Verify(string cslaSource) => Verify(cslaSource, true);
 
-    public static Task Verify(string cslaSource, string additionalSource) => Verify(cslaSource, additionalSource, 2);
+    public static Task Verify(string cslaSource, TestAnalyzerConfigOptionsProvider globalCompilerOptions) => Verify(cslaSource, "", t => t, 2, true, globalCompilerOptions);
 
-    public static Task Verify(string cslaSource, string additionalSource, int expectedFileCount) => Verify(cslaSource, additionalSource, s => s, expectedFileCount);
+    public static Task Verify(string cslaSource, bool enableNullableContext) => Verify(cslaSource, "", enableNullableContext);
 
-    public static Task Verify(string cslaSource, Func<SettingsTask, SettingsTask> configureVerify) => Verify(cslaSource, "", configureVerify, 2);
+    public static Task Verify(string cslaSource, string additionalSource) => Verify(cslaSource, additionalSource, true);
 
-    public static Task Verify(string cslaSource, string additionalSource, Func<SettingsTask, SettingsTask> configureVerify, int expectedFileCount) {
+    public static Task Verify(string cslaSource, string additionalSource, bool enableNullableContext) => Verify(cslaSource, additionalSource, 2, enableNullableContext);
+
+    public static Task Verify(string cslaSource, string additionalSource, int expectedFileCount) => Verify(cslaSource, additionalSource, expectedFileCount, true);
+
+    public static Task Verify(string cslaSource, string additionalSource, int expectedFileCount, bool enableNullableContext) => Verify(cslaSource, additionalSource, s => s, expectedFileCount, enableNullableContext);
+
+    public static Task Verify(string cslaSource, Func<SettingsTask, SettingsTask> configureVerify) => Verify(cslaSource, "", configureVerify, 2, true);
+
+    public static Task Verify(string cslaSource, string additionalSource, Func<SettingsTask, SettingsTask> configureVerify, int expectedFileCount, bool enableNullableContext, TestAnalyzerConfigOptionsProvider? globalCompilerOptions = null) {
 
         var syntaxTrees = new List<SyntaxTree>() {
             CSharpSyntaxTree.ParseText(ClassToGenerateExtensionsInto), // ExtensionClassTree
@@ -44,21 +55,25 @@ public static Task Verify(string cslaSource, string additionalSource, Func<Setti
                 assemblyName: "GeneratorTests",
                 syntaxTrees: syntaxTrees,
                 references: references,
-                new CSharpCompilationOptions(OutputKind.DynamicallyLinkedLibrary)
+                new CSharpCompilationOptions(OutputKind.DynamicallyLinkedLibrary).WithNullableContextOptions(enableNullableContext ? NullableContextOptions.Enable : NullableContextOptions.Disable)
             );
 
         var generator = new DataPortalExtensionGenerator();
 
-        GeneratorDriver driver = CSharpGeneratorDriver.Create(generator);
+        var driver = CSharpGeneratorDriver.Create(generator).WithUpdatedAnalyzerConfigOptions(globalCompilerOptions ?? TestAnalyzerConfigOptionsProvider.Empty);
+
+        driver = driver.RunGeneratorsAndUpdateCompilation(compilation, out var outputCompilation, out var diagnostics);
 
-        driver = driver.RunGeneratorsAndUpdateCompilation(compilation, out var outputCompilation, out var _);
+        using (new AssertionScope()) {
+            outputCompilation.GetDiagnostics().Should().BeEmpty();
+            diagnostics.Should().BeEmpty();
+        }
 
-        outputCompilation.GetDiagnostics().Should().BeEmpty();
         return configureVerify(
             Verifier.Verify(CreateResultFromRun(driver, expectedFileCount))
                 .UseDirectory("Snapshots")
                 .ScrubLinesContaining(StringComparison.Ordinal, ".GeneratedCode(\"Ossendorf.Csla.Dataportal")
-        //.AutoVerify()
+            //.AutoVerify()
         );
     }
 
@@ -74,7 +89,13 @@ private static RunResultWithIgnoreList CreateResultFromRun(GeneratorDriver drive
     public static void Diagnostic(string portalExtensionClass, string expectedDiagnosticId) 
         => Diagnostic(portalExtensionClass, "", expectedDiagnosticId);
 
-    public static void Diagnostic(string portalExtensionClass, string cslaClass, string expectedDiagnosticId) {
+    public static void Diagnostic(string portalExtensionClass, string cslaClass, string expectedDiagnosticId) 
+        => Diagnostic(portalExtensionClass, cslaClass, null, diagnostics => diagnostics.Should().OnlyContain(d => d.Id == expectedDiagnosticId), d => { });
+
+    public static void Diagnostic(string validExtensionClass, string cslaClass, string expectedDiagnosticId, TestAnalyzerConfigOptionsProvider globalCompilerOptions)
+        => Diagnostic(validExtensionClass, cslaClass, globalCompilerOptions, diagnostics => diagnostics.Should().OnlyContain(d => d.Id == expectedDiagnosticId), d => { });
+
+    public static void Diagnostic(string portalExtensionClass, string cslaClass, AnalyzerConfigOptionsProvider? globalConfigOptionsProvider, Action<IEnumerable<Diagnostic>> sourceGenReportedDiagnostics, Action<IEnumerable<Diagnostic>> compilerReportedDiagnostics, NullableContextOptions nullableContextOptions = NullableContextOptions.Enable) {
         var syntaxTrees = new List<SyntaxTree>() {
             CSharpSyntaxTree.ParseText(portalExtensionClass), // ExtensionClassTree
         };
@@ -93,14 +114,17 @@ public static void Diagnostic(string portalExtensionClass, string cslaClass, str
                 assemblyName: "GeneratorTests",
                 syntaxTrees: syntaxTrees,
                 references: references,
-                new CSharpCompilationOptions(OutputKind.DynamicallyLinkedLibrary)
+                new CSharpCompilationOptions(OutputKind.DynamicallyLinkedLibrary).WithNullableContextOptions(nullableContextOptions)
             );
 
         var generator = new DataPortalExtensionGenerator();
 
-        GeneratorDriver driver = CSharpGeneratorDriver.Create(generator);
+        var driver = CSharpGeneratorDriver.Create(generator).WithUpdatedAnalyzerConfigOptions(globalConfigOptionsProvider ?? TestAnalyzerConfigOptionsProvider.Empty);
 
         driver = driver.RunGeneratorsAndUpdateCompilation(compilation, out var outputCompilation, out var diagnostics);
-        diagnostics.Should().OnlyContain(d => d.Id == expectedDiagnosticId);
+        using (new AssertionScope()) {
+            sourceGenReportedDiagnostics(diagnostics);
+            compilerReportedDiagnostics(outputCompilation.GetDiagnostics());
+        }
     }
 }
\ No newline at end of file