diff --git a/Directory.Build.props b/Directory.Build.props
index 4797b4f0..39a8f51d 100644
--- a/Directory.Build.props
+++ b/Directory.Build.props
@@ -47,7 +47,7 @@
     <PackageValidationBaselineVersion>17.0.0</PackageValidationBaselineVersion>
     <Product>ClangSharp</Product>
     <RootNamespace>ClangSharp</RootNamespace>
-    <VersionPrefix>18.1.0.3</VersionPrefix>
+    <VersionPrefix>18.1.0.4</VersionPrefix>
     <VersionSuffix Condition="'$(EXCLUDE_SUFFIX_FROM_VERSION)' != 'true'">rc1</VersionSuffix>
     <VersionSuffix Condition="'$(GITHUB_EVENT_NAME)' == 'pull_request'">pr</VersionSuffix>
   </PropertyGroup>
diff --git a/scripts/build.ps1 b/scripts/build.ps1
index 5558ed50..882eba52 100644
--- a/scripts/build.ps1
+++ b/scripts/build.ps1
@@ -20,7 +20,7 @@ $ErrorActionPreference = "Stop"
 
 function Build() {
   $logFile = Join-Path -Path $LogDir -ChildPath "$configuration\build.binlog"
-  & dotnet build -c "$configuration" --no-restore -v "$verbosity" /bl:"$logFile" /err "$properties" "$solution"
+  & dotnet build -c "$configuration" --no-restore -v "$verbosity" /bl:"$logFile" /err $properties "$solution"
 
   if ($LastExitCode -ne 0) {
     throw "'Build' failed for '$solution'"
@@ -57,7 +57,7 @@ function Help() {
 
 function Pack() {
   $logFile = Join-Path -Path $LogDir -ChildPath "$configuration\pack.binlog"
-  & dotnet pack -c "$configuration" --no-build --no-restore -v "$verbosity" /bl:"$logFile" /err "$properties" "$solution"
+  & dotnet pack -c "$configuration" --no-build --no-restore -v "$verbosity" /bl:"$logFile" /err $properties "$solution"
 
   if ($LastExitCode -ne 0) {
     throw "'Pack' failed for '$solution'"
@@ -66,7 +66,7 @@ function Pack() {
 
 function Restore() {
   $logFile = Join-Path -Path $LogDir -ChildPath "$configuration\restore.binlog"
-  & dotnet restore -v "$verbosity" /bl:"$logFile" /err "$properties" "$solution"
+  & dotnet restore -v "$verbosity" /bl:"$logFile" /err $properties "$solution"
 
   if ($LastExitCode -ne 0) {
     throw "'Restore' failed for '$solution'"
@@ -75,7 +75,7 @@ function Restore() {
 
 function Test() {
   $logFile = Join-Path -Path $LogDir -ChildPath "$configuration\test.binlog"
-  & dotnet test -c "$configuration" --no-build --no-restore -v "$verbosity" /bl:"$logFile" /err "$properties" "$solution"
+  & dotnet test -c "$configuration" --no-build --no-restore -v "$verbosity" /bl:"$logFile" /err $properties "$solution"
 
   if ($LastExitCode -ne 0) {
     throw "'Test' failed for '$solution'"
diff --git a/sources/ClangSharp.Interop/clangsharp/clangsharp.cs b/sources/ClangSharp.Interop/clangsharp/clangsharp.cs
index 91979977..540329f0 100644
--- a/sources/ClangSharp.Interop/clangsharp/clangsharp.cs
+++ b/sources/ClangSharp.Interop/clangsharp/clangsharp.cs
@@ -1043,6 +1043,9 @@ public static partial class @clangsharp
     [DllImport("libClangSharp", CallingConvention = CallingConvention.Cdecl, EntryPoint = "clangsharp_Type_getOriginalType", ExactSpelling = true)]
     public static extern CXType Type_getOriginalType(CXType CT);
 
+    [DllImport("libClangSharp", CallingConvention = CallingConvention.Cdecl, EntryPoint = "clangsharp_Type_getSubstTemplateTypeParamAssociatedDecl", ExactSpelling = true)]
+    public static extern CXCursor Type_getSubstTemplateTypeParamAssociatedDecl(CXType CT);
+
     [DllImport("libClangSharp", CallingConvention = CallingConvention.Cdecl, EntryPoint = "clangsharp_Type_getOwnedTagDecl", ExactSpelling = true)]
     public static extern CXCursor Type_getOwnedTagDecl(CXType CT);
 
diff --git a/sources/ClangSharp.PInvokeGenerator/Abstractions/FunctionOrDelegateDesc.cs b/sources/ClangSharp.PInvokeGenerator/Abstractions/FunctionOrDelegateDesc.cs
index d05c90b3..0a33d680 100644
--- a/sources/ClangSharp.PInvokeGenerator/Abstractions/FunctionOrDelegateDesc.cs
+++ b/sources/ClangSharp.PInvokeGenerator/Abstractions/FunctionOrDelegateDesc.cs
@@ -21,6 +21,7 @@ internal struct FunctionOrDelegateDesc
     public bool HasBody { get; set; }
     public bool IsInherited { get; set; }
     public bool NeedsUnscopedRef { get; set; }
+    public string[]? ParameterTypes { get; set; }
 
     public bool IsVirtual
     {
diff --git a/sources/ClangSharp.PInvokeGenerator/CSharp/CSharpOutputBuilder.VisitDecl.cs b/sources/ClangSharp.PInvokeGenerator/CSharp/CSharpOutputBuilder.VisitDecl.cs
index 712f8c81..8380a582 100644
--- a/sources/ClangSharp.PInvokeGenerator/CSharp/CSharpOutputBuilder.VisitDecl.cs
+++ b/sources/ClangSharp.PInvokeGenerator/CSharp/CSharpOutputBuilder.VisitDecl.cs
@@ -372,6 +372,12 @@ public void BeginFunctionOrDelegate(in FunctionOrDelegateDesc desc, ref bool isM
                 Write(desc.ParentName);
                 Write('.');
                 Write(desc.EscapedName);
+                if (desc.ParameterTypes is not null)
+                {
+                    Write('(');
+                    Write(string.Join(", ", desc.ParameterTypes));
+                    Write(')');
+                }
                 WriteLine("\" />");
             }
             else
diff --git a/sources/ClangSharp.PInvokeGenerator/PInvokeGenerator.VisitDecl.cs b/sources/ClangSharp.PInvokeGenerator/PInvokeGenerator.VisitDecl.cs
index c1e270f5..2e37bb02 100644
--- a/sources/ClangSharp.PInvokeGenerator/PInvokeGenerator.VisitDecl.cs
+++ b/sources/ClangSharp.PInvokeGenerator/PInvokeGenerator.VisitDecl.cs
@@ -501,6 +501,7 @@ private void VisitFunctionDecl(FunctionDecl functionDecl)
         var name = GetRemappedCursorName(functionDecl);
 
         var cxxMethodDecl = functionDecl as CXXMethodDecl;
+        uint overloadCount = 0;
 
         if (cxxMethodDecl is not null and CXXConstructorDecl)
         {
@@ -509,6 +510,11 @@ private void VisitFunctionDecl(FunctionDecl functionDecl)
             name = GetRemappedCursorName(parent);
         }
 
+        if (cxxMethodDecl is not null)
+        {
+            overloadCount = GetOverloadCount(cxxMethodDecl);
+        }
+
         var isManualImport = _config.WithManualImports.Contains(name);
 
         var className = name;
@@ -622,6 +628,7 @@ private void VisitFunctionDecl(FunctionDecl functionDecl)
                 }
             },
             CustomAttrGeneratorData = (functionDecl, _outputBuilder, this),
+            ParameterTypes = overloadCount > 1 ? functionDecl.Parameters.Select(param => GetTargetTypeName(param, out var _)).ToArray() : null,
         };
         Debug.Assert(_outputBuilder is not null);
 
@@ -1404,7 +1411,15 @@ private void VisitRecordDecl(RecordDecl recordDecl)
                     var className = GetClass(uuidName);
 
                     _testOutputBuilder.AddUsingDirective("System");
-                    _testOutputBuilder.AddUsingDirective($"static {GetNamespace(className)}.{className}");
+
+                    if (_config.DontUseUsingStaticsForGuidMember)
+                    {
+                        _testOutputBuilder.AddUsingDirective($"{GetNamespace(className)}");
+                    }
+                    else
+                    {
+                        _testOutputBuilder.AddUsingDirective($"static {GetNamespace(className)}.{className}");
+                    }
 
                     _testOutputBuilder.WriteIndented("/// <summary>Validates that the <see cref=\"Guid\" /> of the <see cref=\"");
                     _testOutputBuilder.Write(escapedName);
@@ -1433,7 +1448,13 @@ private void VisitRecordDecl(RecordDecl recordDecl)
                         _testOutputBuilder.Write("Is.EqualTo(");
                     }
 
-                    _testOutputBuilder.Write(uuidName);
+                    var usableUuidName = uuidName;
+                    if (_config.DontUseUsingStaticsForGuidMember)
+                    {
+                        usableUuidName = $"{className}.{usableUuidName}";
+                    }
+
+                    _testOutputBuilder.Write(usableUuidName);
 
                     if (_config.GenerateTestsNUnit)
                     {
@@ -1619,12 +1640,26 @@ private void VisitRecordDecl(RecordDecl recordDecl)
                 _outputBuilder.EmitUsingDirective("System");
                 _outputBuilder.EmitUsingDirective("System.Runtime.CompilerServices");
 
-                _outputBuilder.EmitUsingDirective($"static {GetNamespace(uuidClassName)}.{uuidClassName}");
+                if (_config.DontUseUsingStaticsForGuidMember)
+                {
+                    _outputBuilder.EmitUsingDirective($"{GetNamespace(uuidClassName)}");
+                }
+                else
+                {
+                    _outputBuilder.EmitUsingDirective($"static {GetNamespace(uuidClassName)}.{uuidClassName}");
+                }
+
+                var usableUuidName = uuidName;
+                if (_config.DontUseUsingStaticsForGuidMember)
+                {
+                    usableUuidName = $"{uuidClassName}.{usableUuidName}";
+                }
+
                 _outputBuilder.BeginValue(in valueDesc);
 
                 var code = _outputBuilder.BeginCSharpCode();
                 code.Write("(Guid*)Unsafe.AsPointer(ref Unsafe.AsRef(in ");
-                code.Write(uuidName);
+                code.Write(usableUuidName);
                 code.Write("))");
                 _outputBuilder.EndCSharpCode(code);
 
diff --git a/sources/ClangSharp.PInvokeGenerator/PInvokeGenerator.cs b/sources/ClangSharp.PInvokeGenerator/PInvokeGenerator.cs
index 0984aaf3..d3a32d63 100644
--- a/sources/ClangSharp.PInvokeGenerator/PInvokeGenerator.cs
+++ b/sources/ClangSharp.PInvokeGenerator/PInvokeGenerator.cs
@@ -3096,6 +3096,39 @@ uint GetOverloadIndex(CXXMethodDecl cxxMethodDeclToMatch, CXXRecordDecl cxxRecor
         }
     }
 
+    private uint GetOverloadCount(CXXMethodDecl cxxMethodDeclToMatch)
+    {
+        var parent = cxxMethodDeclToMatch.Parent;
+        Debug.Assert(parent is not null);
+
+        return GetOverloadIndex(cxxMethodDeclToMatch, parent, baseCount: 0);
+
+        uint GetOverloadIndex(CXXMethodDecl cxxMethodDeclToMatch, CXXRecordDecl cxxRecordDecl, uint baseCount)
+        {
+            var count = baseCount;
+
+            foreach (var cxxBaseSpecifier in cxxRecordDecl.Bases)
+            {
+                var baseCxxRecordDecl = GetRecordDecl(cxxBaseSpecifier);
+                count = GetOverloadIndex(cxxMethodDeclToMatch, baseCxxRecordDecl, count);
+            }
+
+            foreach (var cxxMethodDecl in cxxRecordDecl.Methods)
+            {
+                if (IsExcluded(cxxMethodDecl))
+                {
+                    continue;
+                }
+                else if (cxxMethodDecl.Name == cxxMethodDeclToMatch.Name)
+                {
+                    count++;
+                }
+            }
+
+            return count;
+        }
+    }
+
     private CXXRecordDecl GetRecordDecl(CXXBaseSpecifier cxxBaseSpecifier)
     {
         var baseType = cxxBaseSpecifier.Type;
diff --git a/sources/ClangSharp.PInvokeGenerator/PInvokeGeneratorConfiguration.cs b/sources/ClangSharp.PInvokeGenerator/PInvokeGeneratorConfiguration.cs
index e36133e0..53eacc0b 100644
--- a/sources/ClangSharp.PInvokeGenerator/PInvokeGeneratorConfiguration.cs
+++ b/sources/ClangSharp.PInvokeGenerator/PInvokeGeneratorConfiguration.cs
@@ -267,6 +267,8 @@ public IReadOnlyCollection<string> ExcludedNames
 
     public bool StripEnumMemberTypeName => _options.HasFlag(PInvokeGeneratorConfigurationOptions.StripEnumMemberTypeName);
 
+    public bool DontUseUsingStaticsForGuidMember => _options.HasFlag(PInvokeGeneratorConfigurationOptions.DontUseUsingStaticsForGuidMember);
+
     public string HeaderText => _headerText;
 
     [AllowNull]
diff --git a/sources/ClangSharp.PInvokeGenerator/PInvokeGeneratorConfigurationOptions.cs b/sources/ClangSharp.PInvokeGenerator/PInvokeGeneratorConfigurationOptions.cs
index c2a34293..cd77e71c 100644
--- a/sources/ClangSharp.PInvokeGenerator/PInvokeGeneratorConfigurationOptions.cs
+++ b/sources/ClangSharp.PInvokeGenerator/PInvokeGeneratorConfigurationOptions.cs
@@ -88,4 +88,6 @@ public enum PInvokeGeneratorConfigurationOptions : long
     GenerateGenericPointerWrapper = 1L << 38,
 
     StripEnumMemberTypeName = 1L << 39,
+
+    DontUseUsingStaticsForGuidMember = 1L << 40,
 }
diff --git a/sources/ClangSharp/Cursors/Decls/TemplateTypeParmDecl.cs b/sources/ClangSharp/Cursors/Decls/TemplateTypeParmDecl.cs
index f68532c1..ca0f4b1f 100644
--- a/sources/ClangSharp/Cursors/Decls/TemplateTypeParmDecl.cs
+++ b/sources/ClangSharp/Cursors/Decls/TemplateTypeParmDecl.cs
@@ -5,13 +5,14 @@
 using ClangSharp.Interop;
 using static ClangSharp.Interop.CXCursorKind;
 using static ClangSharp.Interop.CX_DeclKind;
+using static ClangSharp.Interop.CXTypeKind;
 
 namespace ClangSharp;
 
 public sealed class TemplateTypeParmDecl : TypeDecl
 {
     private readonly Lazy<IReadOnlyList<Expr>> _associatedConstraints;
-    private readonly Lazy<Type> _defaultArgument;
+    private readonly Lazy<Type?> _defaultArgument;
 
     internal TemplateTypeParmDecl(CXCursor handle) : base(handle, CXCursor_TemplateTypeParameter, CX_DeclKind_TemplateTypeParm)
     {
@@ -27,12 +28,15 @@ internal TemplateTypeParmDecl(CXCursor handle) : base(handle, CXCursor_TemplateT
 
             return associatedConstraints;
         });
-        _defaultArgument = new Lazy<Type>(() => TranslationUnit.GetOrCreate<Type>(Handle.DefaultArgType));
+        _defaultArgument = new Lazy<Type?>(() => {
+            CXType defaultArgType = Handle.DefaultArgType;
+            return defaultArgType.kind == CXType_Invalid ? null : TranslationUnit.GetOrCreate<Type>(defaultArgType);
+        });
     }
 
     public IReadOnlyList<Expr> AssociatedConstraints => _associatedConstraints.Value;
 
-    public Type DefaultArgument => _defaultArgument.Value;
+    public Type? DefaultArgument => _defaultArgument.Value;
 
     public bool DefaultArgumentWasInherited => Handle.HasInheritedDefaultArg;
 
diff --git a/sources/ClangSharp/Types/SubstTemplateTypeParmType.cs b/sources/ClangSharp/Types/SubstTemplateTypeParmType.cs
index 517d387b..d09e2a5c 100644
--- a/sources/ClangSharp/Types/SubstTemplateTypeParmType.cs
+++ b/sources/ClangSharp/Types/SubstTemplateTypeParmType.cs
@@ -9,14 +9,21 @@ namespace ClangSharp;
 
 public sealed class SubstTemplateTypeParmType : Type
 {
+    private readonly Lazy<Decl?> _associatedDecl;
     private readonly Lazy<TemplateTypeParmType> _replacedParameter;
 
     internal SubstTemplateTypeParmType(CXType handle) : base(handle, CXType_Unexposed, CX_TypeClass_SubstTemplateTypeParm)
     {
+        _associatedDecl = new Lazy<Decl?>(() => {
+            CXCursor cursor = clangsharp.Type_getSubstTemplateTypeParamAssociatedDecl(Handle);
+            return cursor.IsNull ? null : TranslationUnit.GetOrCreate<Decl>(cursor);
+        });
         _replacedParameter = new Lazy<TemplateTypeParmType>(() => TranslationUnit.GetOrCreate<TemplateTypeParmType>(Handle.OriginalType));
     }
 
     public TemplateTypeParmType ReplacedParameter => _replacedParameter.Value;
 
     public Type ReplacementType => Desugar;
+
+    public Decl? AssociatedDecl => _associatedDecl.Value;
 }
diff --git a/sources/ClangSharpPInvokeGenerator/Program.cs b/sources/ClangSharpPInvokeGenerator/Program.cs
index 322ef1e4..8bad0657 100644
--- a/sources/ClangSharpPInvokeGenerator/Program.cs
+++ b/sources/ClangSharpPInvokeGenerator/Program.cs
@@ -444,6 +444,13 @@ public static void Run(InvocationContext context)
                     break;
                 }
 
+                case "exclude-using-statics-for-guid-members":
+                case "dont-use-using-statics-for-guid-members":
+                {
+                    configOptions |= PInvokeGeneratorConfigurationOptions.DontUseUsingStaticsForGuidMember;
+                    break;
+                }
+
                 // VTBL Options
 
                 case "explicit-vtbls":
diff --git a/sources/libClangSharp/ClangSharp.cpp b/sources/libClangSharp/ClangSharp.cpp
index 5880900c..d0f0c8a9 100644
--- a/sources/libClangSharp/ClangSharp.cpp
+++ b/sources/libClangSharp/ClangSharp.cpp
@@ -26,10 +26,38 @@ using namespace clang::cxstring;
 using namespace clang::cxtu;
 using namespace clang::cxtype;
 
+CXTemplateArgumentKind ConvertTemplateArgumentKind(TemplateArgument::ArgKind kind) {
+    switch (kind) {
+    case TemplateArgument::Null:
+        return CXTemplateArgumentKind_Null;
+    case TemplateArgument::Type:
+        return CXTemplateArgumentKind_Type;
+    case TemplateArgument::Declaration:
+        return CXTemplateArgumentKind_Declaration;
+    case TemplateArgument::NullPtr:
+        return CXTemplateArgumentKind_NullPtr;
+    case TemplateArgument::Integral:
+        return CXTemplateArgumentKind_Integral;
+    case TemplateArgument::StructuralValue:
+        // Does not exist in CXTemplateArgumentKind
+        return CXTemplateArgumentKind_Invalid;
+    case TemplateArgument::Template:
+        return CXTemplateArgumentKind_Template;
+    case TemplateArgument::TemplateExpansion:
+        return CXTemplateArgumentKind_TemplateExpansion;
+    case TemplateArgument::Expression:
+        return CXTemplateArgumentKind_Expression;
+    case TemplateArgument::Pack:
+        return CXTemplateArgumentKind_Pack;
+    default:
+        return CXTemplateArgumentKind_Invalid;
+    }
+}
+
 CX_TemplateArgument MakeCXTemplateArgument(const TemplateArgument* TA, CXTranslationUnit TU, bool needsDispose = false) {
     if (TA) {
         assert(TU && "Invalid arguments!");
-        return { static_cast<CXTemplateArgumentKind>(TA->getKind()), (needsDispose ? 1 : 0), TA, TU };
+        return { ConvertTemplateArgumentKind(TA->getKind()), (needsDispose ? 1 : 0), TA, TU };
     }
 
     return { };
@@ -1009,15 +1037,19 @@ CXCursor clangsharp_Cursor_getDefaultArg(CXCursor C) {
 }
 
 CXType clangsharp_Cursor_getDefaultArgType(CXCursor C) {
+    QualType QT;
+
     if (isDeclOrTU(C.kind)) {
         const Decl* D = getCursorDecl(C);
 
         if (const TemplateTypeParmDecl* TTPD = dyn_cast<TemplateTypeParmDecl>(D)) {
-            return MakeCXType(TTPD->getDefaultArgument(), getCursorTU(C));
+            if (TTPD->hasDefaultArgument()) {
+                QT = TTPD->getDefaultArgument();
+            }
         }
     }
 
-    return MakeCXType(QualType(), getCursorTU(C));
+    return MakeCXType(QT, getCursorTU(C));
 }
 
 CXCursor clangsharp_Cursor_getDefinition(CXCursor C) {
@@ -5369,6 +5401,17 @@ CXType clangsharp_Type_getOriginalType(CXType CT) {
     return MakeCXType(QualType(), GetTypeTU(CT));
 }
 
+CXCursor clangsharp_Type_getSubstTemplateTypeParamAssociatedDecl(CXType CT) {
+    QualType T = GetQualType(CT);
+    const Type* TP = T.getTypePtrOrNull();
+
+    if (const SubstTemplateTypeParmType* STTPT = dyn_cast<SubstTemplateTypeParmType>(TP)) {
+        return MakeCXCursor(STTPT->getAssociatedDecl(), GetTypeTU(CT));
+    }
+
+    clang_getNullCursor();
+}
+
 CXCursor clangsharp_Type_getOwnedTagDecl(CXType CT) {
     QualType T = GetQualType(CT);
     const Type* TP = T.getTypePtrOrNull();
diff --git a/sources/libClangSharp/ClangSharp.h b/sources/libClangSharp/ClangSharp.h
index 01120c2b..b7ea675a 100644
--- a/sources/libClangSharp/ClangSharp.h
+++ b/sources/libClangSharp/ClangSharp.h
@@ -841,6 +841,8 @@ CLANGSHARP_LINKAGE int clangsharp_Type_getNumRows(CXType CT);
 
 CLANGSHARP_LINKAGE CXType clangsharp_Type_getOriginalType(CXType CT);
 
+CLANGSHARP_LINKAGE CXCursor clangsharp_Type_getSubstTemplateTypeParamAssociatedDecl(CXType CT);
+
 CLANGSHARP_LINKAGE CXCursor clangsharp_Type_getOwnedTagDecl(CXType CT);
 
 CLANGSHARP_LINKAGE CXType clangsharp_Type_getPointeeType(CXType CT);
diff --git a/tests/ClangSharp.UnitTests/CursorTests/DeclTest.cs b/tests/ClangSharp.UnitTests/CursorTests/DeclTest.cs
index 067280f1..e216b73b 100644
--- a/tests/ClangSharp.UnitTests/CursorTests/DeclTest.cs
+++ b/tests/ClangSharp.UnitTests/CursorTests/DeclTest.cs
@@ -74,4 +74,27 @@ class MyClass<int, U>
         var templateParameter = classTemplatePartialSpecializationDecl.TemplateParameters.Single();
         Assert.That(templateParameter.Name, Is.EqualTo("U"));
     }
+
+    [Test]
+    [Ignore("TODO: LibClangSharp needs to be recompiled first")]
+    public void TemplateParameterPackTest()
+    {
+        var inputContents = $@"template<class... Types>
+class tuple;
+
+tuple<int, long> SomeFunction();
+";
+
+        using var translationUnit = CreateTranslationUnit(inputContents);
+
+        var functionDecl = translationUnit.TranslationUnitDecl.Decls.OfType<FunctionDecl>().Single();
+        var tupleDecl = functionDecl.ReturnType.AsCXXRecordDecl as ClassTemplateSpecializationDecl;
+        Assert.That(tupleDecl, Is.Not.Null);
+        Assert.That(tupleDecl!.TemplateArgs.Count, Is.EqualTo(1));
+
+        var packElements = tupleDecl.TemplateArgs[0].PackElements;
+        Assert.That(packElements.Count, Is.EqualTo(2));
+        Assert.That(packElements[0].AsType.AsString, Is.EqualTo("int"));
+        Assert.That(packElements[1].AsType.AsString, Is.EqualTo("long"));
+    }
 }