diff --git a/src/ast.h b/src/ast.h
index 1431c18..ba0d174 100644
--- a/src/ast.h
+++ b/src/ast.h
@@ -11,6 +11,7 @@ namespace AST {
     class Node {
     public:
         virtual std::string formatted() = 0;
+        virtual ~Node() = default;
     };
 
     class Expression : public Node {
@@ -20,6 +21,7 @@ namespace AST {
 
     class Type {
     public:
+        virtual ~Type() = default;
         virtual std::string formatted() = 0;
         virtual llvm::Type* codegen(codegen::Builder& builder) = 0;
     };
@@ -34,6 +36,7 @@ namespace AST {
         int m_value;
     public:
         IntLiteralExpression(int value) : m_value{ value } {}
+        virtual ~IntLiteralExpression() override = default;
         virtual std::string formatted() override;
         virtual llvm::Value* codegen(codegen::Builder& builder) override;
     };
@@ -44,6 +47,7 @@ namespace AST {
         std::unique_ptr<Expression> m_expr;
     public:
         ReturnStatement(std::unique_ptr<Expression> expr) : m_expr{ std::move(expr) } {}
+        virtual ~ReturnStatement() override = default;
         virtual std::string formatted() override;
         virtual void codegen(codegen::Builder& builder) override;
     };
@@ -70,6 +74,7 @@ namespace AST {
             , m_name{ name }
             , m_statements{ std::move(statements) } {
         }
+        virtual ~Function() override = default;
         virtual std::string formatted() override;
         virtual void codegen(codegen::Builder& builder) override;
     };
@@ -83,6 +88,7 @@ namespace AST {
         FundamentalTypeKind m_ty;
     public:
         FundamentalType(FundamentalTypeKind kind) : m_ty{ kind } {}
+        virtual ~FundamentalType() override = default;
         virtual std::string formatted() override;
         virtual llvm::Type* codegen(codegen::Builder& builder) override;
     };