diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
index 89c798e..3dfaf52 100644
--- a/.github/workflows/publish.yml
+++ b/.github/workflows/publish.yml
@@ -35,7 +35,7 @@ jobs:
             - name: Upload Artifacts
               uses: actions/upload-artifact@v4
               with:
-                name: Vertex
+                name: Mamba
                 path: |
                     build/macosx/arm64/release/Jvav
                     build/windows/x64/release/Jvav.exe
diff --git a/src/Mamba/Code Analysis/Diagnostic.cpp b/src/Mamba/Code Analysis/Diagnostic.cpp
index 829ed99..f0cdf3a 100644
--- a/src/Mamba/Code Analysis/Diagnostic.cpp	
+++ b/src/Mamba/Code Analysis/Diagnostic.cpp	
@@ -1,10 +1,10 @@
 #include "Diagnostic.h"
+
 #include "MambaCore.h"
 
 namespace Mamba
 {
-    Diagnostic::Diagnostic(const DiagnosticSeverity Severity,
-                           const TextLocation Location,
+    Diagnostic::Diagnostic(const DiagnosticSeverity Severity, const TextLocation Location,
                            const std::shared_ptr<const String> Message) noexcept :
         Severity(Severity), Location(Location), Message(Message)
     {
diff --git a/src/Mamba/Code Analysis/Diagnostic.h b/src/Mamba/Code Analysis/Diagnostic.h
index 29b9982..352f5ec 100644
--- a/src/Mamba/Code Analysis/Diagnostic.h	
+++ b/src/Mamba/Code Analysis/Diagnostic.h	
@@ -1,6 +1,7 @@
 #pragma once
 
 #include "MambaCore.h"
+
 #include "TextLocation.h"
 #include <memory>
 
@@ -16,8 +17,7 @@ namespace Mamba
     class Diagnostic final
     {
     public:
-        [[nodiscard]] Diagnostic(const DiagnosticSeverity Severity,
-                                 const TextLocation Location,
+        [[nodiscard]] Diagnostic(const DiagnosticSeverity Severity, const TextLocation Location,
                                  const std::shared_ptr<const String> Message) noexcept;
 
         const DiagnosticSeverity Severity;
diff --git a/src/Mamba/Code Analysis/DiagnosticBag.h b/src/Mamba/Code Analysis/DiagnosticBag.h
index 30a92c5..d16d4e3 100644
--- a/src/Mamba/Code Analysis/DiagnosticBag.h	
+++ b/src/Mamba/Code Analysis/DiagnosticBag.h	
@@ -1,12 +1,11 @@
 #pragma once
 
-#include "MambaCore.h"
-#include "SyntaxKind.h"
-#include "TextLocation.h"
-
 #include <memory>
 #include <vector>
 
+#include "SyntaxKind.h"
+#include "TextLocation.h"
+
 namespace Mamba
 {
     class DiagnosticBag : public std::vector<std::shared_ptr<const class Diagnostic>>
diff --git a/src/Mamba/Code Analysis/Syntax/ExpressionSyntax.cpp b/src/Mamba/Code Analysis/Syntax/ExpressionSyntax.cpp
index 2a646bc..fc212c9 100644
--- a/src/Mamba/Code Analysis/Syntax/ExpressionSyntax.cpp	
+++ b/src/Mamba/Code Analysis/Syntax/ExpressionSyntax.cpp	
@@ -1,5 +1,7 @@
 #include "ExpressionSyntax.h"
 
+#include "SyntaxTree.h"
+
 namespace Mamba
 {
     ExpressionSyntax::ExpressionSyntax(const std::shared_ptr<const class SyntaxTree> SyntaxTree) noexcept :
diff --git a/src/Mamba/Code Analysis/Syntax/Lexer.cpp b/src/Mamba/Code Analysis/Syntax/Lexer.cpp
index 3ff49a5..8744760 100644
--- a/src/Mamba/Code Analysis/Syntax/Lexer.cpp	
+++ b/src/Mamba/Code Analysis/Syntax/Lexer.cpp	
@@ -1,6 +1,7 @@
 #include "Lexer.h"
+
 #include "DiagnosticBag.h"
-#include "MambaCore.h"
+#include "Literal.h"
 #include "SourceText.h"
 #include "SyntaxFacts.h"
 #include "SyntaxKind.h"
@@ -16,11 +17,11 @@
 namespace Mamba
 {
     Lexer::Lexer(const std::shared_ptr<const class SyntaxTree> SyntaxTree) :
-        SyntaxTree(SyntaxTree), Text(SyntaxTree->Text), Start(), Position(), Kind(SyntaxKind::BadToken)
+        SyntaxTree(SyntaxTree), Text(SyntaxTree->Text), Position(), Start(), Kind(SyntaxKind::BadToken)
     {
     }
 
-    std::shared_ptr<const class SyntaxToken> Lexer::Lex() noexcept
+    std::shared_ptr<const SyntaxToken> Lexer::Lex() noexcept
     {
         const auto TokenStart = Position;
 
diff --git a/src/Mamba/Code Analysis/Syntax/Lexer.h b/src/Mamba/Code Analysis/Syntax/Lexer.h
index 1a1ffe1..b026e46 100644
--- a/src/Mamba/Code Analysis/Syntax/Lexer.h	
+++ b/src/Mamba/Code Analysis/Syntax/Lexer.h	
@@ -1,7 +1,6 @@
 #pragma once
 
 #include "DiagnosticBag.h"
-#include "Literal.h"
 #include "MambaCore.h"
 #include "SourceText.h"
 #include "SyntaxKind.h"
@@ -20,7 +19,7 @@ namespace Mamba
         std::size_t Start;
 
         SyntaxKind Kind;
-        NullableSharedPtr<Literal> Value;
+        NullableSharedPtr<struct Literal> Value;
 
     public:
         DiagnosticBag Diagnostics;
@@ -84,7 +83,7 @@ namespace Mamba
 
         // Report an invalid number diagnostic with the specified base and literal
         template<std::size_t Base>
-        void ReportInvalidNumber(const TextSpan& Span, const StringView& Literal)
+        void ReportInvalidNumber(const TextSpan Span, const StringView Literal)
 
             requires(Base == 2 || Base == 8 || Base == 10 || Base == 16)
         {
diff --git a/src/Mamba/Code Analysis/Syntax/Literal.cpp b/src/Mamba/Code Analysis/Syntax/Literal.cpp
index bab07ab..de91799 100644
--- a/src/Mamba/Code Analysis/Syntax/Literal.cpp	
+++ b/src/Mamba/Code Analysis/Syntax/Literal.cpp	
@@ -18,7 +18,7 @@ namespace Mamba
     Literal::Literal() noexcept {}
 
     Literal::Literal(const std::shared_ptr<String> String) noexcept :
-        StringValue(String), Value(StringView(*String)), Type(LiteralType::String)
+        Value(StringView(*String)), Type(LiteralType::String), StringValue(String)
     {
     }
 
diff --git a/src/Mamba/Code Analysis/Syntax/Literal.h b/src/Mamba/Code Analysis/Syntax/Literal.h
index 4b95eba..8200903 100644
--- a/src/Mamba/Code Analysis/Syntax/Literal.h	
+++ b/src/Mamba/Code Analysis/Syntax/Literal.h	
@@ -1,8 +1,10 @@
 #pragma once
 
 #include "MambaCore.h"
+
 #include <cstdint>
 #include <memory>
+#include <optional>
 
 namespace Mamba
 {
@@ -43,7 +45,7 @@ namespace Mamba
         LiteralValue(const LiteralValue&) = default;
         LiteralValue(LiteralValue&&) = default;
 
-        friend class Literal;
+        friend struct Literal;
     };
 
     enum class LiteralType
@@ -74,7 +76,7 @@ namespace Mamba
         LiteralValue Value;
         LiteralType Type;
 
-        std::optional<std::shared_ptr<const String>> StringValue;
+        ::std::optional<std::shared_ptr<const String>> StringValue;
 
         [[nodiscard]] Literal() noexcept;
         [[nodiscard]] Literal(const std::shared_ptr<String> String) noexcept;
diff --git a/src/Mamba/Code Analysis/Syntax/LiteralExpressionSyntax.cpp b/src/Mamba/Code Analysis/Syntax/LiteralExpressionSyntax.cpp
index ff75efc..8a6eb93 100644
--- a/src/Mamba/Code Analysis/Syntax/LiteralExpressionSyntax.cpp	
+++ b/src/Mamba/Code Analysis/Syntax/LiteralExpressionSyntax.cpp	
@@ -1,19 +1,20 @@
 #include "LiteralExpressionSyntax.h"
 
+#include "Literal.h"
 #include "SyntaxToken.h"
+#include "SyntaxTree.h"
 
 namespace Mamba
 {
-    LiteralExpressionSyntax::LiteralExpressionSyntax(
-        const std::shared_ptr<const class SyntaxTree> SyntaxTree,
-        const std::shared_ptr<const class SyntaxToken> LiteralToken) noexcept :
+    LiteralExpressionSyntax::LiteralExpressionSyntax(const std::shared_ptr<const class SyntaxTree> SyntaxTree,
+                                                     const std::shared_ptr<const SyntaxToken> LiteralToken) noexcept :
         Super(SyntaxTree), LiteralToken(LiteralToken), Value(LiteralToken->Value)
     {
     }
 
     LiteralExpressionSyntax::LiteralExpressionSyntax(const std::shared_ptr<const class SyntaxTree> SyntaxTree,
-                                                     const std::shared_ptr<const class SyntaxToken> LiteralToken,
-                                                     const std::shared_ptr<const class Literal> Value) noexcept :
+                                                     const std::shared_ptr<const SyntaxToken> LiteralToken,
+                                                     const std::shared_ptr<const Literal> Value) noexcept :
         Super(SyntaxTree), LiteralToken(LiteralToken), Value(Value)
     {
     }
diff --git a/src/Mamba/Code Analysis/Syntax/LiteralExpressionSyntax.h b/src/Mamba/Code Analysis/Syntax/LiteralExpressionSyntax.h
index 72b0945..78a958b 100644
--- a/src/Mamba/Code Analysis/Syntax/LiteralExpressionSyntax.h	
+++ b/src/Mamba/Code Analysis/Syntax/LiteralExpressionSyntax.h	
@@ -17,12 +17,15 @@ namespace Mamba
 
         [[nodiscard]] LiteralExpressionSyntax(const std::shared_ptr<const class SyntaxTree> SyntaxTree,
                                               const std::shared_ptr<const class SyntaxToken> LiteralToken,
-                                              const std::shared_ptr<const class Literal> Value) noexcept;
+                                              // msvc bug, struct keyword is required here, class is not allowed
+                                              // https://eel.is/c++draft/dcl.dcl#dcl.type.elab-7
+                                              // https://zh.cppreference.com/w/cpp/language/elaborated_type_specifier
+                                              const std::shared_ptr<const struct Literal> Value) noexcept;
 
         virtual SyntaxKind Kind() const noexcept override;
         virtual std::vector<std::shared_ptr<const class SyntaxNode>> Children() const noexcept override;
 
         const std::shared_ptr<const class SyntaxToken> LiteralToken;
-        const std::shared_ptr<const class Literal> Value;
+        const std::shared_ptr<const struct Literal> Value;
     };
 } // namespace Mamba
\ No newline at end of file
diff --git a/src/Mamba/Code Analysis/Syntax/Parser.cpp b/src/Mamba/Code Analysis/Syntax/Parser.cpp
index fed2907..ced4de9 100644
--- a/src/Mamba/Code Analysis/Syntax/Parser.cpp	
+++ b/src/Mamba/Code Analysis/Syntax/Parser.cpp	
@@ -1,34 +1,41 @@
 #include "Parser.h"
+
+#include <memory>
+
 #include "AssignmentExpressionSyntax.h"
 #include "BinaryExpressionSyntax.h"
+#include "BlockStatementSyntax.h"
 #include "BreakStatementSyntax.h"
 #include "CallExpressionSyntax.h"
+#include "CompilationUnitSyntax.h"
 #include "ContinueStatementSyntax.h"
 #include "DoWhileStatementSyntax.h"
+#include "ElseClauseSyntax.h"
+#include "ExpressionStatementSyntax.h"
 #include "ExpressionSyntax.h"
 #include "ForStatementSyntax.h"
+#include "FunctionDeclarationSyntax.h"
 #include "GlobalStatementSyntax.h"
 #include "IfStatementSyntax.h"
 #include "Lexer.h"
+#include "Literal.h"
 #include "LiteralExpressionSyntax.h"
 #include "MambaCore.h"
 #include "NameExpressionSyntax.h"
 #include "ParameterSyntax.h"
 #include "ParenthesizedExpressionSyntax.h"
 #include "ReturnStatementSyntax.h"
+#include "StatementSyntax.h"
 #include "SyntaxFacts.h"
 #include "SyntaxKind.h"
 #include "SyntaxNode.h"
 #include "SyntaxToken.h"
 #include "SyntaxTree.h"
+#include "TypeClauseSyntax.h"
 #include "UnaryExpressionSyntax.h"
 #include "VariableDeclarationSyntax.h"
-
-#include "MambaCore.h"
 #include "WhileStatementSyntax.h"
 
-#include <memory>
-
 namespace Mamba
 {
     Parser::Parser(const std::shared_ptr<const class SyntaxTree> SyntaxTree) noexcept :
@@ -234,8 +241,8 @@ namespace Mamba
         }
 
         const auto CloseBraceToken = MatchToken(SyntaxKind::CloseBraceToken);
-        return std::make_shared<BlockStatementSyntax>(SyntaxTree, OpenBraceToken, std::move(Statements),
-                                                      CloseBraceToken);
+        return std::make_shared<const BlockStatementSyntax>(SyntaxTree, OpenBraceToken, std::move(Statements),
+                                                            CloseBraceToken);
     }
 
     std::shared_ptr<const StatementSyntax> Parser::ParseVariableDeclaration() noexcept
@@ -354,7 +361,7 @@ namespace Mamba
     std::shared_ptr<const ExpressionStatementSyntax> Parser::ParseExpressionStatement() noexcept
     {
         const auto Expression = ParseExpression();
-        return std::make_shared<ExpressionStatementSyntax>(SyntaxTree, Expression);
+        return std::make_shared<const ExpressionStatementSyntax>(SyntaxTree, Expression);
     }
 
     std::shared_ptr<const ExpressionSyntax> Parser::ParseExpression() noexcept
@@ -451,26 +458,27 @@ namespace Mamba
         const auto Left = MatchToken(SyntaxKind::OpenParenthesisToken);
         const auto Expression = ParseExpression();
         const auto Right = MatchToken(SyntaxKind::CloseParenthesisToken);
-        return std::make_shared<ParenthesizedExpressionSyntax>(SyntaxTree, Left, Expression, Right);
+        return std::make_shared<const ParenthesizedExpressionSyntax>(SyntaxTree, Left, Expression, Right);
     }
 
     std::shared_ptr<const class ExpressionSyntax> Parser::ParseBooleanLiteral() noexcept
     {
         const auto IsTrue = Current()->Kind() == SyntaxKind::TrueKeyword;
         const auto KeywordToken = MatchToken(IsTrue ? SyntaxKind::TrueKeyword : SyntaxKind::FalseKeyword);
-        return std::make_shared<LiteralExpressionSyntax>(SyntaxTree, KeywordToken, std::make_shared<Literal>(IsTrue));
+        return std::make_shared<const LiteralExpressionSyntax>(SyntaxTree, KeywordToken,
+                                                               std::make_shared<const Literal>(IsTrue));
     }
 
     std::shared_ptr<const class ExpressionSyntax> Parser::ParseNumericLiteral() noexcept
     {
         const auto NumberToken = MatchToken(SyntaxKind::NumberToken);
-        return std::make_shared<LiteralExpressionSyntax>(SyntaxTree, NumberToken);
+        return std::make_shared<const LiteralExpressionSyntax>(SyntaxTree, NumberToken);
     }
 
     std::shared_ptr<const class ExpressionSyntax> Parser::ParseStringLiteral() noexcept
     {
         const auto StringToken = MatchToken(SyntaxKind::StringToken);
-        return std::make_shared<LiteralExpressionSyntax>(SyntaxTree, StringToken);
+        return std::make_shared<const LiteralExpressionSyntax>(SyntaxTree, StringToken);
     }
 
     std::shared_ptr<const class ExpressionSyntax> Parser::ParseNameOrCallExpression() noexcept
diff --git a/src/Mamba/Code Analysis/Syntax/Parser.h b/src/Mamba/Code Analysis/Syntax/Parser.h
index e99317b..3561cc4 100644
--- a/src/Mamba/Code Analysis/Syntax/Parser.h	
+++ b/src/Mamba/Code Analysis/Syntax/Parser.h	
@@ -1,21 +1,10 @@
 #pragma once
 
-#include "BlockStatementSyntax.h"
-#include "CompilationUnitSyntax.h"
+#include <memory>
+#include <vector>
+
 #include "DiagnosticBag.h"
-#include "ElseClauseSyntax.h"
-#include "ExpressionStatementSyntax.h"
-#include "ExpressionSyntax.h"
-#include "FunctionDeclarationSyntax.h"
-#include "MambaCore.h"
-#include "MemberSyntax.h"
-#include "ParameterSyntax.h"
 #include "SeperatedSyntaxList.h"
-#include "StatementSyntax.h"
-#include "SyntaxKind.h"
-#include "SyntaxToken.h"
-#include "TypeClauseSyntax.h"
-#include <memory>
 
 namespace Mamba
 {
diff --git a/src/Mamba/Code Analysis/Syntax/SeperatedSyntaxList.h b/src/Mamba/Code Analysis/Syntax/SeperatedSyntaxList.h
index 52965f0..06246c0 100644
--- a/src/Mamba/Code Analysis/Syntax/SeperatedSyntaxList.h	
+++ b/src/Mamba/Code Analysis/Syntax/SeperatedSyntaxList.h	
@@ -12,7 +12,11 @@ namespace Mamba
         [[nodiscard]] constexpr Container<T> SkipSeperators(Container<T>&& NodesAndSeparators) const noexcept
         {
             auto Result = Container<T>(NodesAndSeparators.size() / 2);
+#if __cpp_size_t_suffix == 202011L
             for (auto Index = 0uz; Index < NodesAndSeparators.size() / 2; ++Index)
+#else
+            for (auto Index = std::size_t(); Index < NodesAndSeparators.size() / 2; ++Index)
+#endif
             {
                 Result[Index] = std::move(NodesAndSeparators[Index * 2]);
             }
diff --git a/src/Mamba/Code Analysis/Syntax/SyntaxFacts.cpp b/src/Mamba/Code Analysis/Syntax/SyntaxFacts.cpp
index 3f9dc37..6bc8e18 100644
--- a/src/Mamba/Code Analysis/Syntax/SyntaxFacts.cpp	
+++ b/src/Mamba/Code Analysis/Syntax/SyntaxFacts.cpp	
@@ -356,12 +356,9 @@ namespace Mamba
                 return TEXT("AssignmentExpression");
             case SyntaxKind::CallExpression:
                 return TEXT("CallExpression");
-            deafult:
+            default:
                 return TEXT("Unknown");
         }
-
-        // GCC & MSVC reports that control reaches end of non-void function [-Wreturn-type]
-        std::unreachable();
     }
 
     bool SyntaxFacts::IsKeyword(const SyntaxKind Kind) noexcept
diff --git a/src/Mamba/Code Analysis/Syntax/SyntaxNode.cpp b/src/Mamba/Code Analysis/Syntax/SyntaxNode.cpp
index 871e1db..43da8f2 100644
--- a/src/Mamba/Code Analysis/Syntax/SyntaxNode.cpp	
+++ b/src/Mamba/Code Analysis/Syntax/SyntaxNode.cpp	
@@ -1,5 +1,6 @@
-#include "SyntaxNode.h"
+#include "SyntaxNode.h"
 
+#include "Literal.h"
 #include "MambaCore.h"
 #include "SourceText.h"
 #include "SyntaxFacts.h"
@@ -16,6 +17,8 @@ namespace Mamba
     {
     }
 
+    SyntaxNode::~SyntaxNode() noexcept {}
+
     const std::shared_ptr<const class SyntaxNode> SyntaxNode::Parent() const noexcept
     {
         return SyntaxTree->GetParent(shared_from_this());
@@ -185,7 +188,7 @@ namespace Mamba
 
         const auto LastChild = Node->Children().size() == 0 ? nullptr : Node->Children().back();
 
-        for (const auto Child : Node->Children())
+        for (auto&& Child : Node->Children())
         {
             PrettyPrint(Stream, Child, Indent, Child == LastChild);
         }
diff --git a/src/Mamba/Code Analysis/Syntax/SyntaxNode.h b/src/Mamba/Code Analysis/Syntax/SyntaxNode.h
index 27f1127..c4b93c7 100644
--- a/src/Mamba/Code Analysis/Syntax/SyntaxNode.h	
+++ b/src/Mamba/Code Analysis/Syntax/SyntaxNode.h	
@@ -16,6 +16,8 @@ namespace Mamba
         [[nodiscard]] SyntaxNode(const std::shared_ptr<const class SyntaxTree> SyntaxTree) noexcept;
 
     public:
+        virtual ~SyntaxNode() noexcept;
+
         const std::shared_ptr<const class SyntaxTree> SyntaxTree;
 
         [[nodiscard]] const NullableSharedPtr<const class SyntaxNode> Parent() const noexcept;
diff --git a/src/Mamba/Code Analysis/Syntax/SyntaxToken.cpp b/src/Mamba/Code Analysis/Syntax/SyntaxToken.cpp
index b194fa7..51276f7 100644
--- a/src/Mamba/Code Analysis/Syntax/SyntaxToken.cpp	
+++ b/src/Mamba/Code Analysis/Syntax/SyntaxToken.cpp	
@@ -4,12 +4,10 @@
 
 namespace Mamba
 {
-    SyntaxToken::SyntaxToken(const std::shared_ptr<const class SyntaxTree> SyntaxTree,
-                             const SyntaxKind Kind,
-                             const std::size_t Position,
-                             const std::shared_ptr<const String> Text,
+    SyntaxToken::SyntaxToken(const std::shared_ptr<const class SyntaxTree> SyntaxTree, const SyntaxKind Kind,
+                             const std::size_t Position, const std::shared_ptr<const String> Text,
                              const NullableSharedPtr<Literal> Value) noexcept :
-        Super(SyntaxTree), KindValue(Kind), Position(Position), Text(Text), Value(Value)
+        Super(SyntaxTree), Position(Position), Text(Text), Value(Value), KindValue(Kind)
     {
     }
 
diff --git a/src/Mamba/Code Analysis/Syntax/SyntaxToken.h b/src/Mamba/Code Analysis/Syntax/SyntaxToken.h
index 0e6fbc3..b1dba93 100644
--- a/src/Mamba/Code Analysis/Syntax/SyntaxToken.h	
+++ b/src/Mamba/Code Analysis/Syntax/SyntaxToken.h	
@@ -1,6 +1,5 @@
 #pragma once
 
-#include "Literal.h"
 #include "MambaCore.h"
 #include "SyntaxKind.h"
 #include "SyntaxNode.h"
@@ -14,11 +13,9 @@ namespace Mamba
         using Super = SyntaxNode;
 
     public:
-        [[nodiscard]] SyntaxToken(const std::shared_ptr<const class SyntaxTree> SyntaxTree,
-                                  const SyntaxKind Kind,
-                                  const std::size_t Position,
-                                  const std::shared_ptr<const String> Text,
-                                  const NullableSharedPtr<Literal> Value) noexcept;
+        [[nodiscard]] SyntaxToken(const std::shared_ptr<const class SyntaxTree> SyntaxTree, const SyntaxKind Kind,
+                                  const std::size_t Position, const std::shared_ptr<const String> Text,
+                                  const NullableSharedPtr<struct Literal> Value) noexcept;
 
         virtual SyntaxKind Kind() const noexcept override;
 
diff --git a/src/Mamba/Code Analysis/Syntax/SyntaxTree.cpp b/src/Mamba/Code Analysis/Syntax/SyntaxTree.cpp
index bf5530b..0f91dde 100644
--- a/src/Mamba/Code Analysis/Syntax/SyntaxTree.cpp	
+++ b/src/Mamba/Code Analysis/Syntax/SyntaxTree.cpp	
@@ -1,9 +1,12 @@
 #include "SyntaxTree.h"
+
+#include "CompilationUnitSyntax.h"
 #include "Lexer.h"
 #include "MambaCore.h"
 #include "Parser.h"
 #include "SourceText.h"
 #include "SyntaxKind.h"
+#include "SyntaxNode.h"
 #include "SyntaxToken.h"
 
 #include <fast_io.h>
diff --git a/src/Mamba/Code Analysis/Syntax/SyntaxTree.h b/src/Mamba/Code Analysis/Syntax/SyntaxTree.h
index ef81caa..11ec31f 100644
--- a/src/Mamba/Code Analysis/Syntax/SyntaxTree.h	
+++ b/src/Mamba/Code Analysis/Syntax/SyntaxTree.h	
@@ -1,9 +1,9 @@
 #pragma once
 
 #include "MambaCore.h"
-#include "TextLine.h"
 
 #include <memory>
+#include <optional>
 #include <unordered_map>
 #include <utility>
 #include <vector>
diff --git a/src/Mamba/Code Analysis/Syntax/VariableDeclarationSyntax.h b/src/Mamba/Code Analysis/Syntax/VariableDeclarationSyntax.h
index c27208d..681a4c4 100644
--- a/src/Mamba/Code Analysis/Syntax/VariableDeclarationSyntax.h	
+++ b/src/Mamba/Code Analysis/Syntax/VariableDeclarationSyntax.h	
@@ -1,11 +1,9 @@
 #pragma once
 
-#include "MambaCore.h"
-#include "StatementSyntax.h"
-#include "TypeClauseSyntax.h"
-
 #include <memory>
 
+#include "StatementSyntax.h"
+
 namespace Mamba
 {
     class VariableDeclarationSyntax : public StatementSyntax
diff --git a/src/Mamba/Code Analysis/Text/SourceText.cpp b/src/Mamba/Code Analysis/Text/SourceText.cpp
index 6a824a2..69df70c 100644
--- a/src/Mamba/Code Analysis/Text/SourceText.cpp	
+++ b/src/Mamba/Code Analysis/Text/SourceText.cpp	
@@ -25,8 +25,13 @@ namespace Mamba
     {
         auto Result = std::vector<std::shared_ptr<const TextLine>>();
 
+#if __cpp_size_t_suffix == 202011L
         auto Position = 0uz;
         auto LineStart = 0uz;
+#else
+        auto Position = std::size_t();
+        auto LineStart = std::size_t();
+#endif
 
         while (Position < Text.length())
         {
@@ -89,7 +94,11 @@ namespace Mamba
 
     std::size_t SourceText::GetLineIndex(const std::size_t Position) const noexcept
     {
+#if __cpp_size_t_suffix == 202011L
         auto Lower = 0uz;
+#else
+        auto Lower = std::size_t();
+#endif
         auto Upper = Lines.size() - 1;
 
         while (Lower <= Upper)
diff --git a/src/Mamba/Code Analysis/Text/SourceText.h b/src/Mamba/Code Analysis/Text/SourceText.h
index 5ac8fd0..dc0d24e 100644
--- a/src/Mamba/Code Analysis/Text/SourceText.h	
+++ b/src/Mamba/Code Analysis/Text/SourceText.h	
@@ -1,6 +1,7 @@
 #pragma once
 
 #include "MambaCore.h"
+#include "TextSpan.h"
 
 #include <memory>
 #include <vector>
@@ -31,10 +32,17 @@ namespace Mamba
         [[nodiscard]] static std::size_t GetLineBreakWidth(const String& Text, const std::size_t Position) noexcept;
 
     public:
+#if __cpp_explicit_this_parameter == 202110L
         [[nodiscard]] auto&& operator[](this auto&& Self, const std::size_t Position) noexcept
         {
             return (*std::forward<decltype(Self)>(Self).Text)[Position];
         }
+#else
+        [[nodiscard]] Char operator[](const std::size_t Position) const noexcept
+        {
+            return (*Text)[Position];
+        }
+#endif
 
         [[nodiscard]] std::size_t Length() const noexcept;
 
@@ -45,10 +53,10 @@ namespace Mamba
         [[nodiscard]] std::shared_ptr<String> ToString(const std::size_t Start,
                                                        const std::size_t Length) const noexcept;
 
-        [[nodiscard]] std::shared_ptr<const String> ToString(const class TextSpan Span) const noexcept;
+        [[nodiscard]] std::shared_ptr<const String> ToString(const TextSpan Span) const noexcept;
 
         [[nodiscard]] StringView ToView(const std::size_t Start, const std::size_t Length) const noexcept;
 
-        [[nodiscard]] StringView ToView(const class TextSpan Span) const noexcept;
+        [[nodiscard]] StringView ToView(const TextSpan Span) const noexcept;
     };
 } // namespace Mamba
diff --git a/src/Mamba/Code Analysis/Text/TextLine.h b/src/Mamba/Code Analysis/Text/TextLine.h
index 42ae275..e1756b3 100644
--- a/src/Mamba/Code Analysis/Text/TextLine.h	
+++ b/src/Mamba/Code Analysis/Text/TextLine.h	
@@ -16,13 +16,11 @@ namespace Mamba
         std::size_t End() const noexcept;
         const std::size_t LengthIncludeLineBreak;
 
-        class TextSpan Span() const noexcept;
-        class TextSpan SpanIncludeLineBreak() const noexcept;
+        struct TextSpan Span() const noexcept;
+        struct TextSpan SpanIncludeLineBreak() const noexcept;
 
-        [[nodiscard]] TextLine(const std::shared_ptr<const class SourceText> Text,
-                               const std::size_t Start,
-                               const std::size_t Length,
-                               const std::size_t LengthIncludeLineBreak) noexcept;
+        [[nodiscard]] TextLine(const std::shared_ptr<const class SourceText> Text, const std::size_t Start,
+                               const std::size_t Length, const std::size_t LengthIncludeLineBreak) noexcept;
 
         [[nodiscard]] std::shared_ptr<const String> ToString() const noexcept;
     };
diff --git a/src/Mamba/MambaCore.h b/src/Mamba/MambaCore.h
index c634dc2..f620b81 100644
--- a/src/Mamba/MambaCore.h
+++ b/src/Mamba/MambaCore.h
@@ -5,6 +5,7 @@
 #include <utility>
 
 #include <fast_io.h>
+#include <fast_io_unit/string.h>
 
 #define MAMBA_NAMESPACE_BEGIN \
     namespace Mamba           \
diff --git a/src/main.cpp b/src/main.cpp
index 6174f5a..a5fa51f 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,11 +1,12 @@
-#include "CompilationUnitSyntax.h"
-#include "fast_io_core_impl/codecvt/general.h"
-#include "fast_io_core_impl/error.h"
-#include "fast_io_unit/string_impl/concat.h"
-#include "MambaCore.h"
-#include "SyntaxTree.h"
 #include <fast_io.h>
 #include <memory>
+#include <print>
+
+#include "Diagnostic.h"
+#include "MambaCore.h"
+#include "SyntaxTree.h"
+
+#include "CompilationUnitSyntax.h"
 
 int main(int argc, char* argv[])
 {
@@ -14,11 +15,30 @@ int main(int argc, char* argv[])
         for (auto i = 1; i < argc; ++i)
         {
             auto Argument = fast_io::mnp::os_c_str(argv[i]);
-            fast_io::io::perrln("Compiling: ", Argument);
+            fast_io::io::println("Compiling: ", Argument);
             const auto SyntaxTree = Mamba::SyntaxTree::Load(
                 std::make_shared<const Mamba::String>(fast_io::u8concat(fast_io::mnp::code_cvt(Argument))));
 
             fast_io::io::println(fast_io::mnp::code_cvt(SyntaxTree.Root()->ToString()));
+
+            if (!SyntaxTree.Diagnostics().empty())
+            {
+                for (auto&& Diagnostic : SyntaxTree.Diagnostics())
+                {
+                    if (Diagnostic->Severity == Mamba::DiagnosticSeverity::Error)
+                    {
+                        fast_io::io::println("Error: ", fast_io::mnp::code_cvt(*Diagnostic->Message));
+                    }
+                    else if (Diagnostic->Severity == Mamba::DiagnosticSeverity::Warning)
+                    {
+                        fast_io::io::println("Warning: ", fast_io::mnp::code_cvt(*Diagnostic->Message));
+                    }
+                    else
+                    {
+                        fast_io::io::println("Info: ", fast_io::mnp::code_cvt(*Diagnostic->Message));
+                    }
+                }
+            }
         }
     }
     catch (const std::exception& exception)
@@ -29,4 +49,4 @@ int main(int argc, char* argv[])
     {
         fast_io::io::perrln(exception);
     }
-}
+}
\ No newline at end of file
diff --git a/xmake.lua b/xmake.lua
index fc0cd14..e308a92 100644
--- a/xmake.lua
+++ b/xmake.lua
@@ -10,8 +10,11 @@ target("Jvav")
     set_languages("clatest", "c++latest")
     add_packages("fast_io")
     set_toolchains("llvm")
+    set_warnings("all")
     add_includedirs("src/Mamba", "src/Mamba/Code Analysis", "src/Mamba/Code Analysis/Syntax", "src/Mamba/Code Analysis/Text")
-    add_linkdirs("/opt/homebrew/opt/llvm/lib/c++") -- macOS compability
+    if is_os("macosx") then
+        add_linkdirs("/opt/homebrew/opt/llvm/lib/c++") -- macOS compability
+    end
     if is_mode("release") then
         set_optimize("fastest")
     end