diff --git a/Userland/Libraries/LibCodeComprehension/Shell/ShellComprehensionEngine.cpp b/Userland/Libraries/LibCodeComprehension/Shell/ShellComprehensionEngine.cpp
index 26230ad3b97..504343f0014 100644
--- a/Userland/Libraries/LibCodeComprehension/Shell/ShellComprehensionEngine.cpp
+++ b/Userland/Libraries/LibCodeComprehension/Shell/ShellComprehensionEngine.cpp
@@ -180,7 +180,7 @@ Optional<CodeComprehension::ProjectLocation> ShellComprehensionEngine::find_decl
         return {};
     }
 
-    auto name = static_ptr_cast<::Shell::AST::BarewordLiteral>(result.matching_node)->text();
+    auto name = static_ptr_cast<::Shell::AST::BarewordLiteral const>(result.matching_node)->text();
     auto& declarations = all_declarations();
     for (auto& entry : declarations) {
         for (auto& declaration : entry.value) {
@@ -209,7 +209,7 @@ void ShellComprehensionEngine::update_declared_symbols(DocumentData const& docum
 
                 DeprecatedString name;
                 if (literal->is_bareword())
-                    name = static_ptr_cast<::Shell::AST::BarewordLiteral>(literal)->text();
+                    name = static_ptr_cast<::Shell::AST::BarewordLiteral const>(literal)->text();
 
                 if (!name.is_empty()) {
                     dbgln("Found variable {}", name);
diff --git a/Userland/Shell/AST.cpp b/Userland/Shell/AST.cpp
index 3d83b301937..838b5e01f75 100644
--- a/Userland/Shell/AST.cpp
+++ b/Userland/Shell/AST.cpp
@@ -260,7 +260,7 @@ void Node::clear_syntax_error()
     m_syntax_error_node->clear_syntax_error();
 }
 
-void Node::set_is_syntax_error(SyntaxError const& error_node)
+void Node::set_is_syntax_error(SyntaxError& error_node)
 {
     if (!m_syntax_error_node) {
         m_syntax_error_node = error_node;
@@ -331,14 +331,14 @@ Node::Node(Position position)
 {
 }
 
-Vector<Line::CompletionSuggestion> Node::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result)
+Vector<Line::CompletionSuggestion> Node::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result) const
 {
     auto matching_node = hit_test_result.matching_node;
     if (matching_node) {
         auto kind = matching_node->kind();
         StringLiteral::EnclosureType enclosure_type = StringLiteral::EnclosureType::None;
         if (kind == Kind::StringLiteral)
-            enclosure_type = static_cast<StringLiteral*>(matching_node.ptr())->enclosure_type();
+            enclosure_type = static_cast<StringLiteral const*>(matching_node.ptr())->enclosure_type();
 
         auto set_results_trivia = [enclosure_type](Vector<Line::CompletionSuggestion>&& suggestions) {
             if (enclosure_type != StringLiteral::EnclosureType::None) {
@@ -352,12 +352,12 @@ Vector<Line::CompletionSuggestion> Node::complete_for_editor(Shell& shell, size_
             StringView text;
             size_t corrected_offset;
             if (kind == Kind::BarewordLiteral) {
-                auto* node = static_cast<BarewordLiteral*>(matching_node.ptr());
+                auto* node = static_cast<BarewordLiteral const*>(matching_node.ptr());
                 text = node->text();
                 escape_mode = Shell::EscapeMode::Bareword;
                 corrected_offset = find_offset_into_node(text, offset - matching_node->position().start_offset, escape_mode);
             } else {
-                auto* node = static_cast<StringLiteral*>(matching_node.ptr());
+                auto* node = static_cast<StringLiteral const*>(matching_node.ptr());
                 text = node->text();
                 escape_mode = enclosure_type == StringLiteral::EnclosureType::SingleQuotes ? Shell::EscapeMode::SingleQuotedString : Shell::EscapeMode::DoubleQuotedString;
                 corrected_offset = find_offset_into_node(text, offset - matching_node->position().start_offset + 1, escape_mode);
@@ -382,9 +382,9 @@ Vector<Line::CompletionSuggestion> Node::complete_for_editor(Shell& shell, size_
 
             DeprecatedString program_name;
             if (program_name_node->is_bareword())
-                program_name = static_cast<BarewordLiteral*>(program_name_node.ptr())->text();
+                program_name = static_cast<BarewordLiteral const*>(program_name_node.ptr())->text();
             else
-                program_name = static_cast<StringLiteral*>(program_name_node.ptr())->text();
+                program_name = static_cast<StringLiteral const*>(program_name_node.ptr())->text();
 
             return set_results_trivia(shell.complete_option(program_name, text, corrected_offset, hit_test_result.closest_command_node.ptr(), hit_test_result.matching_node));
         }
@@ -553,7 +553,7 @@ HitTestResult ListConcatenate::hit_test_position(size_t offset) const
     return {};
 }
 
-RefPtr<Node> ListConcatenate::leftmost_trivial_literal() const
+RefPtr<Node const> ListConcatenate::leftmost_trivial_literal() const
 {
     if (m_list.is_empty())
         return nullptr;
@@ -764,14 +764,14 @@ HitTestResult CastToCommand::hit_test_position(size_t offset) const
     return result;
 }
 
-Vector<Line::CompletionSuggestion> CastToCommand::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result)
+Vector<Line::CompletionSuggestion> CastToCommand::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result) const
 {
     auto matching_node = hit_test_result.matching_node;
     if (!matching_node || !matching_node->is_bareword())
         return {};
 
     auto corrected_offset = offset - matching_node->position().start_offset;
-    auto* node = static_cast<BarewordLiteral*>(matching_node.ptr());
+    auto* node = static_cast<BarewordLiteral const*>(matching_node.ptr());
 
     if (corrected_offset > node->text().length())
         return {};
@@ -779,7 +779,7 @@ Vector<Line::CompletionSuggestion> CastToCommand::complete_for_editor(Shell& she
     return shell.complete_program_name(node->text(), corrected_offset);
 }
 
-RefPtr<Node> CastToCommand::leftmost_trivial_literal() const
+RefPtr<Node const> CastToCommand::leftmost_trivial_literal() const
 {
     return m_inner->leftmost_trivial_literal();
 }
@@ -841,7 +841,7 @@ HitTestResult CastToList::hit_test_position(size_t offset) const
     return m_inner->hit_test_position(offset);
 }
 
-RefPtr<Node> CastToList::leftmost_trivial_literal() const
+RefPtr<Node const> CastToList::leftmost_trivial_literal() const
 {
     return m_inner->leftmost_trivial_literal();
 }
@@ -1124,7 +1124,7 @@ HitTestResult FunctionDeclaration::hit_test_position(size_t offset) const
     return result;
 }
 
-Vector<Line::CompletionSuggestion> FunctionDeclaration::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result)
+Vector<Line::CompletionSuggestion> FunctionDeclaration::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result) const
 {
     auto matching_node = hit_test_result.matching_node;
     if (!matching_node)
@@ -1134,7 +1134,7 @@ Vector<Line::CompletionSuggestion> FunctionDeclaration::complete_for_editor(Shel
         return matching_node->complete_for_editor(shell, offset, hit_test_result);
 
     auto corrected_offset = offset - matching_node->position().start_offset - 1; // Skip the first '$'
-    auto* node = static_cast<SimpleVariable*>(matching_node.ptr());
+    auto* node = static_cast<SimpleVariable const*>(matching_node.ptr());
 
     auto name = node->name().substring_view(0, corrected_offset);
 
@@ -1863,14 +1863,14 @@ HitTestResult Execute::hit_test_position(size_t offset) const
     return result;
 }
 
-Vector<Line::CompletionSuggestion> Execute::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result)
+Vector<Line::CompletionSuggestion> Execute::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result) const
 {
     auto matching_node = hit_test_result.matching_node;
     if (!matching_node || !matching_node->is_bareword())
         return {};
 
     auto corrected_offset = offset - matching_node->position().start_offset;
-    auto* node = static_cast<BarewordLiteral*>(matching_node.ptr());
+    auto* node = static_cast<BarewordLiteral const*>(matching_node.ptr());
 
     if (corrected_offset > node->text().length())
         return {};
@@ -2043,7 +2043,7 @@ void ImmediateExpression::highlight_in_editor(Line::Editor& editor, Shell& shell
         editor.stylize({ m_closing_brace_position->start_offset, m_closing_brace_position->end_offset }, { Line::Style::Foreground(Line::Style::XtermColor::Green) });
 }
 
-Vector<Line::CompletionSuggestion> ImmediateExpression::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result)
+Vector<Line::CompletionSuggestion> ImmediateExpression::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result) const
 {
     auto matching_node = hit_test_result.matching_node;
     if (!matching_node || matching_node != this)
@@ -2135,7 +2135,7 @@ HitTestResult Join::hit_test_position(size_t offset) const
     return m_right->hit_test_position(offset);
 }
 
-RefPtr<Node> Join::leftmost_trivial_literal() const
+RefPtr<Node const> Join::leftmost_trivial_literal() const
 {
     if (auto value = m_left->leftmost_trivial_literal())
         return value;
@@ -2558,14 +2558,14 @@ HitTestResult PathRedirectionNode::hit_test_position(size_t offset) const
     return result;
 }
 
-Vector<Line::CompletionSuggestion> PathRedirectionNode::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result)
+Vector<Line::CompletionSuggestion> PathRedirectionNode::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result) const
 {
     auto matching_node = hit_test_result.matching_node;
     if (!matching_node || !matching_node->is_bareword())
         return {};
 
     auto corrected_offset = offset - matching_node->position().start_offset;
-    auto* node = static_cast<BarewordLiteral*>(matching_node.ptr());
+    auto* node = static_cast<BarewordLiteral const*>(matching_node.ptr());
 
     if (corrected_offset > node->text().length())
         return {};
@@ -2810,7 +2810,7 @@ HitTestResult Sequence::hit_test_position(size_t offset) const
     return {};
 }
 
-RefPtr<Node> Sequence::leftmost_trivial_literal() const
+RefPtr<Node const> Sequence::leftmost_trivial_literal() const
 {
     for (auto& entry : m_entries) {
         if (auto node = entry.leftmost_trivial_literal())
@@ -2899,7 +2899,7 @@ HitTestResult Slice::hit_test_position(size_t offset) const
     return m_selector->hit_test_position(offset);
 }
 
-Vector<Line::CompletionSuggestion> Slice::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result)
+Vector<Line::CompletionSuggestion> Slice::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result) const
 {
     // TODO: Maybe intercept this, and suggest values in range?
     return m_selector->complete_for_editor(shell, offset, hit_test_result);
@@ -2958,7 +2958,7 @@ HitTestResult SimpleVariable::hit_test_position(size_t offset) const
     return { this, this, nullptr };
 }
 
-Vector<Line::CompletionSuggestion> SimpleVariable::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result)
+Vector<Line::CompletionSuggestion> SimpleVariable::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result) const
 {
     auto matching_node = hit_test_result.matching_node;
     if (!matching_node)
@@ -3012,7 +3012,7 @@ void SpecialVariable::highlight_in_editor(Line::Editor& editor, Shell& shell, Hi
         m_slice->highlight_in_editor(editor, shell, metadata);
 }
 
-Vector<Line::CompletionSuggestion> SpecialVariable::complete_for_editor(Shell&, size_t, HitTestResult const&)
+Vector<Line::CompletionSuggestion> SpecialVariable::complete_for_editor(Shell&, size_t, HitTestResult const&) const
 {
     return {};
 }
@@ -3134,7 +3134,7 @@ void Juxtaposition::highlight_in_editor(Line::Editor& editor, Shell& shell, High
     }
 }
 
-Vector<Line::CompletionSuggestion> Juxtaposition::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result)
+Vector<Line::CompletionSuggestion> Juxtaposition::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result) const
 {
     auto matching_node = hit_test_result.matching_node;
     if (m_left->would_execute() || m_right->would_execute()) {
@@ -3312,7 +3312,7 @@ SyntaxError::SyntaxError(Position position, DeprecatedString error, bool is_cont
 {
 }
 
-SyntaxError const& SyntaxError::syntax_error_node() const
+SyntaxError& SyntaxError::syntax_error_node()
 {
     return *this;
 }
@@ -3364,7 +3364,7 @@ HitTestResult Tilde::hit_test_position(size_t offset) const
     return { this, this, nullptr };
 }
 
-Vector<Line::CompletionSuggestion> Tilde::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result)
+Vector<Line::CompletionSuggestion> Tilde::complete_for_editor(Shell& shell, size_t offset, HitTestResult const& hit_test_result) const
 {
     auto matching_node = hit_test_result.matching_node;
     if (!matching_node)
@@ -3718,7 +3718,7 @@ NonnullRefPtr<Value> SimpleVariableValue::resolve_without_cast(RefPtr<Shell> she
         if (!m_slices.is_empty())
             result = result->with_slices(m_slices);
 
-        return result;
+        return const_cast<Value&>(*result);
     }
 
     return *this;
@@ -3755,12 +3755,12 @@ Vector<DeprecatedString> SpecialVariableValue::resolve_as_list(RefPtr<Shell> she
         return { resolve_slices(shell, DeprecatedString::number(getpid()), m_slices) };
     case '*':
         if (auto argv = shell->lookup_local_variable("ARGV"sv))
-            return resolve_slices(shell, argv->resolve_as_list(shell), m_slices);
+            return resolve_slices(shell, const_cast<Value&>(*argv).resolve_as_list(shell), m_slices);
         return resolve_slices(shell, Vector<DeprecatedString> {}, m_slices);
     case '#':
         if (auto argv = shell->lookup_local_variable("ARGV"sv)) {
             if (argv->is_list()) {
-                auto list_argv = static_cast<AST::ListValue*>(argv.ptr());
+                auto list_argv = static_cast<AST::ListValue const*>(argv.ptr());
                 return { resolve_slices(shell, DeprecatedString::number(list_argv->values().size()), m_slices) };
             }
             return { resolve_slices(shell, "1", m_slices) };
diff --git a/Userland/Shell/AST.h b/Userland/Shell/AST.h
index 0f1c293ffd0..4d68c7848a4 100644
--- a/Userland/Shell/AST.h
+++ b/Userland/Shell/AST.h
@@ -220,9 +220,9 @@ struct Command {
 };
 
 struct HitTestResult {
-    RefPtr<Node> matching_node;
-    RefPtr<Node> closest_node_with_semantic_meaning; // This is used if matching_node is a bareword
-    RefPtr<Node> closest_command_node;               // This is used if matching_node is a bareword, and it is not the first in a list
+    RefPtr<Node const> matching_node;
+    RefPtr<Node const> closest_node_with_semantic_meaning; // This is used if matching_node is a bareword
+    RefPtr<Node const> closest_command_node;               // This is used if matching_node is a bareword, and it is not the first in a list
 };
 
 class Value : public RefCounted<Value> {
@@ -424,7 +424,7 @@ public:
     virtual void for_each_entry(RefPtr<Shell> shell, Function<IterationDecision(NonnullRefPtr<Value>)> callback);
     virtual RefPtr<Value> run(RefPtr<Shell>) = 0;
     virtual void highlight_in_editor(Line::Editor&, Shell&, HighlightMetadata = {}) = 0;
-    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&);
+    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) const;
     Vector<Line::CompletionSuggestion> complete_for_editor(Shell& shell, size_t offset);
     virtual HitTestResult hit_test_position(size_t offset) const
     {
@@ -451,14 +451,14 @@ public:
 
     Position const& position() const { return m_position; }
     virtual void clear_syntax_error();
-    virtual void set_is_syntax_error(SyntaxError const& error_node);
-    virtual SyntaxError const& syntax_error_node() const
+    virtual void set_is_syntax_error(SyntaxError& error_node);
+    virtual SyntaxError& syntax_error_node()
     {
         VERIFY(is_syntax_error());
         return *m_syntax_error_node;
     }
 
-    virtual RefPtr<Node> leftmost_trivial_literal() const { return nullptr; }
+    virtual RefPtr<Node const> leftmost_trivial_literal() const { return nullptr; }
 
     Vector<Command> to_lazy_evaluated_commands(RefPtr<Shell> shell);
 
@@ -534,7 +534,7 @@ public:
     PathRedirectionNode(Position, int, NonnullRefPtr<Node>);
     virtual ~PathRedirectionNode();
     virtual void highlight_in_editor(Line::Editor&, Shell&, HighlightMetadata = {}) override;
-    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) override;
+    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) const override;
     virtual HitTestResult hit_test_position(size_t offset) const override;
     virtual bool is_command() const override { return true; }
     virtual bool is_list() const override { return true; }
@@ -585,7 +585,7 @@ private:
     virtual void highlight_in_editor(Line::Editor&, Shell&, HighlightMetadata = {}) override;
     virtual HitTestResult hit_test_position(size_t) const override;
     virtual bool is_list() const override { return true; }
-    virtual RefPtr<Node> leftmost_trivial_literal() const override;
+    virtual RefPtr<Node const> leftmost_trivial_literal() const override;
 
     Vector<NonnullRefPtr<Node>> m_list;
 };
@@ -622,7 +622,7 @@ private:
     virtual RefPtr<Value> run(RefPtr<Shell>) override;
     virtual void highlight_in_editor(Line::Editor&, Shell&, HighlightMetadata = {}) override;
     virtual bool is_bareword() const override { return true; }
-    virtual RefPtr<Node> leftmost_trivial_literal() const override { return this; }
+    virtual RefPtr<Node const> leftmost_trivial_literal() const override { return this; }
 
     DeprecatedString m_text;
 };
@@ -659,10 +659,10 @@ private:
     virtual RefPtr<Value> run(RefPtr<Shell>) override;
     virtual void highlight_in_editor(Line::Editor&, Shell&, HighlightMetadata = {}) override;
     virtual HitTestResult hit_test_position(size_t) const override;
-    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) override;
+    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) const override;
     virtual bool is_command() const override { return true; }
     virtual bool is_list() const override { return true; }
-    virtual RefPtr<Node> leftmost_trivial_literal() const override;
+    virtual RefPtr<Node const> leftmost_trivial_literal() const override;
 
     NonnullRefPtr<Node> m_inner;
 };
@@ -683,7 +683,7 @@ private:
     virtual void highlight_in_editor(Line::Editor&, Shell&, HighlightMetadata = {}) override;
     virtual HitTestResult hit_test_position(size_t) const override;
     virtual bool is_list() const override { return true; }
-    virtual RefPtr<Node> leftmost_trivial_literal() const override;
+    virtual RefPtr<Node const> leftmost_trivial_literal() const override;
 
     RefPtr<Node> m_inner;
 };
@@ -849,7 +849,7 @@ private:
     virtual RefPtr<Value> run(RefPtr<Shell>) override;
     virtual void highlight_in_editor(Line::Editor&, Shell&, HighlightMetadata = {}) override;
     virtual HitTestResult hit_test_position(size_t) const override;
-    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) override;
+    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) const override;
     virtual bool would_execute() const override { return true; }
     virtual bool should_override_execution_in_current_process() const override { return true; }
 
@@ -982,7 +982,7 @@ private:
     virtual RefPtr<Value> run(RefPtr<Shell>) override;
     virtual void highlight_in_editor(Line::Editor&, Shell&, HighlightMetadata = {}) override;
     virtual HitTestResult hit_test_position(size_t) const override;
-    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) override;
+    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) const override;
     virtual bool is_execute() const override { return true; }
     virtual bool would_execute() const override { return true; }
 
@@ -1034,7 +1034,7 @@ private:
     virtual void dump(int level) const override;
     virtual RefPtr<Value> run(RefPtr<Shell>) override;
     virtual void highlight_in_editor(Line::Editor&, Shell&, HighlightMetadata = {}) override;
-    Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) override;
+    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) const override;
     virtual HitTestResult hit_test_position(size_t) const override;
 
     NonnullRefPtrVector<AST::Node> m_arguments;
@@ -1059,7 +1059,7 @@ private:
     virtual HitTestResult hit_test_position(size_t) const override;
     virtual bool is_command() const override { return true; }
     virtual bool is_list() const override { return true; }
-    virtual RefPtr<Node> leftmost_trivial_literal() const override;
+    virtual RefPtr<Node const> leftmost_trivial_literal() const override;
 
     NonnullRefPtr<Node> m_left;
     NonnullRefPtr<Node> m_right;
@@ -1204,7 +1204,7 @@ private:
     virtual HitTestResult hit_test_position(size_t) const override;
     virtual bool is_list() const override { return true; }
     virtual bool should_override_execution_in_current_process() const override { return true; }
-    virtual RefPtr<Node> leftmost_trivial_literal() const override;
+    virtual RefPtr<Node const> leftmost_trivial_literal() const override;
 
     NonnullRefPtrVector<Node> m_entries;
     Vector<Position> m_separator_positions;
@@ -1242,7 +1242,7 @@ public:
     virtual void dump(int level) const override;
     virtual RefPtr<Value> run(RefPtr<Shell>) override;
     virtual void highlight_in_editor(Line::Editor&, Shell&, HighlightMetadata = {}) override;
-    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) override;
+    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) const override;
     virtual HitTestResult hit_test_position(size_t) const override;
 
 protected:
@@ -1284,7 +1284,7 @@ private:
     virtual void dump(int level) const override;
     virtual RefPtr<Value> run(RefPtr<Shell>) override;
     virtual void highlight_in_editor(Line::Editor&, Shell&, HighlightMetadata = {}) override;
-    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) override;
+    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) const override;
     virtual HitTestResult hit_test_position(size_t) const override;
     virtual bool is_simple_variable() const override { return true; }
 
@@ -1304,7 +1304,7 @@ private:
     virtual void dump(int level) const override;
     virtual RefPtr<Value> run(RefPtr<Shell>) override;
     virtual void highlight_in_editor(Line::Editor&, Shell&, HighlightMetadata = {}) override;
-    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) override;
+    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) const override;
     virtual HitTestResult hit_test_position(size_t) const override;
 
     char m_name { 0 };
@@ -1329,7 +1329,7 @@ private:
     virtual RefPtr<Value> run(RefPtr<Shell>) override;
     virtual void highlight_in_editor(Line::Editor&, Shell&, HighlightMetadata = {}) override;
     virtual HitTestResult hit_test_position(size_t) const override;
-    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) override;
+    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) const override;
 
     NonnullRefPtr<Node> m_left;
     NonnullRefPtr<Node> m_right;
@@ -1363,7 +1363,7 @@ private:
     virtual RefPtr<Value> run(RefPtr<Shell>) override;
     virtual void highlight_in_editor(Line::Editor&, Shell&, HighlightMetadata = {}) override;
     virtual HitTestResult hit_test_position(size_t) const override;
-    virtual RefPtr<Node> leftmost_trivial_literal() const override { return this; };
+    virtual RefPtr<Node const> leftmost_trivial_literal() const override { return this; };
 
     DeprecatedString m_end;
     bool m_allows_interpolation { false };
@@ -1392,7 +1392,7 @@ private:
     virtual void dump(int level) const override;
     virtual RefPtr<Value> run(RefPtr<Shell>) override;
     virtual void highlight_in_editor(Line::Editor&, Shell&, HighlightMetadata = {}) override;
-    virtual RefPtr<Node> leftmost_trivial_literal() const override { return this; };
+    virtual RefPtr<Node const> leftmost_trivial_literal() const override { return this; };
 
     DeprecatedString m_text;
     EnclosureType m_enclosure_type;
@@ -1431,7 +1431,7 @@ public:
     {
         m_is_cleared = true;
     }
-    virtual void set_is_syntax_error(SyntaxError const& error) override
+    virtual void set_is_syntax_error(SyntaxError& error) override
     {
         m_position = error.position();
         m_is_cleared = error.m_is_cleared;
@@ -1447,7 +1447,7 @@ private:
     virtual RefPtr<Value> run(RefPtr<Shell>) override;
     virtual void highlight_in_editor(Line::Editor&, Shell&, HighlightMetadata = {}) override;
     virtual HitTestResult hit_test_position(size_t) const override { return { nullptr, nullptr, nullptr }; }
-    virtual SyntaxError const& syntax_error_node() const override;
+    virtual SyntaxError& syntax_error_node() override;
 
     DeprecatedString m_syntax_error_text;
     bool m_is_continuable { false };
@@ -1484,7 +1484,7 @@ private:
     virtual void dump(int level) const override;
     virtual RefPtr<Value> run(RefPtr<Shell>) override;
     virtual void highlight_in_editor(Line::Editor&, Shell&, HighlightMetadata = {}) override;
-    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) override;
+    virtual Vector<Line::CompletionSuggestion> complete_for_editor(Shell&, size_t, HitTestResult const&) const override;
     virtual HitTestResult hit_test_position(size_t) const override;
     virtual bool is_tilde() const override { return true; }
 
diff --git a/Userland/Shell/Builtin.cpp b/Userland/Shell/Builtin.cpp
index ad9c03c7a06..a4e78b8604a 100644
--- a/Userland/Shell/Builtin.cpp
+++ b/Userland/Shell/Builtin.cpp
@@ -554,7 +554,7 @@ int Shell::builtin_export(int argc, char const** argv)
         if (parts.size() == 1) {
             auto value = lookup_local_variable(parts[0]);
             if (value) {
-                auto values = value->resolve_as_list(*this);
+                auto values = const_cast<AST::Value&>(*value).resolve_as_list(*this);
                 StringBuilder builder;
                 builder.join(' ', values);
                 parts.append(builder.to_deprecated_string());
@@ -946,9 +946,9 @@ int Shell::builtin_shift(int argc, char const** argv)
     }
 
     if (!argv_->is_list())
-        argv_ = adopt_ref(*new AST::ListValue({ argv_.release_nonnull() }));
+        argv_ = adopt_ref(*new AST::ListValue({ const_cast<AST::Value&>(*argv_) }));
 
-    auto& values = static_cast<AST::ListValue*>(argv_.ptr())->values();
+    auto& values = const_cast<AST::ListValue*>(static_cast<AST::ListValue const*>(argv_.ptr()))->values();
     if ((size_t)count > values.size()) {
         warnln("shift: shift count must not be greater than {}", values.size());
         return 1;
@@ -975,7 +975,7 @@ int Shell::builtin_source(int argc, char const** argv)
     auto previous_argv = lookup_local_variable("ARGV"sv);
     ScopeGuard guard { [&] {
         if (!args.is_empty())
-            set_local_variable("ARGV", move(previous_argv));
+            set_local_variable("ARGV", const_cast<AST::Value&>(*previous_argv));
     } };
 
     if (!args.is_empty())
@@ -1337,7 +1337,7 @@ int Shell::builtin_argsparser_parse(int argc, char const** argv)
     auto enlist = [&](auto name, auto value) -> NonnullRefPtr<AST::Value> {
         auto variable = lookup_local_variable(name);
         if (variable) {
-            auto list = variable->resolve_as_list(*this);
+            auto list = const_cast<AST::Value&>(*variable).resolve_as_list(*this);
             auto new_value = value->resolve_as_string(*this);
             list.append(move(new_value));
             return make_ref_counted<AST::ListValue>(move(list));
diff --git a/Userland/Shell/Formatter.h b/Userland/Shell/Formatter.h
index b1f2cb40593..ac58e54ec25 100644
--- a/Userland/Shell/Formatter.h
+++ b/Userland/Shell/Formatter.h
@@ -117,8 +117,8 @@ private:
     StringView m_source;
     size_t m_output_cursor { 0 };
     ssize_t m_cursor { -1 };
-    RefPtr<AST::Node> m_root_node;
-    AST::Node* m_hit_node { nullptr };
+    RefPtr<AST::Node const> m_root_node;
+    AST::Node const* m_hit_node { nullptr };
 
     const AST::Node* m_parent_node { nullptr };
     const AST::Node* m_last_visited_node { nullptr };
diff --git a/Userland/Shell/Job.cpp b/Userland/Shell/Job.cpp
index 171018b8ecc..919b0593a82 100644
--- a/Userland/Shell/Job.cpp
+++ b/Userland/Shell/Job.cpp
@@ -96,7 +96,7 @@ void Job::set_signalled(int sig)
         on_exit(*this);
 }
 
-void Job::unblock() const
+void Job::unblock()
 {
     if (!m_exited && on_exit)
         on_exit(*this);
diff --git a/Userland/Shell/Job.h b/Userland/Shell/Job.h
index 6f214f1fb40..f6cef51bbad 100644
--- a/Userland/Shell/Job.h
+++ b/Userland/Shell/Job.h
@@ -63,7 +63,7 @@ public:
     bool should_announce_signal() const { return m_should_announce_signal; }
     bool is_suspended() const { return m_is_suspended; }
     bool shell_did_continue() const { return m_shell_did_continue; }
-    void unblock() const;
+    void unblock();
 
     Core::ElapsedTimer& timer() { return m_command_timer; }
 
diff --git a/Userland/Shell/Shell.cpp b/Userland/Shell/Shell.cpp
index 2a2512427a6..ef1e94ac93e 100644
--- a/Userland/Shell/Shell.cpp
+++ b/Userland/Shell/Shell.cpp
@@ -350,7 +350,7 @@ Shell::LocalFrame* Shell::find_frame_containing_local_variable(StringView name)
     return nullptr;
 }
 
-RefPtr<AST::Value> Shell::lookup_local_variable(StringView name) const
+RefPtr<AST::Value const> Shell::lookup_local_variable(StringView name) const
 {
     if (auto* frame = find_frame_containing_local_variable(name))
         return frame->local_variables.get(name).value();
@@ -361,7 +361,7 @@ RefPtr<AST::Value> Shell::lookup_local_variable(StringView name) const
     return nullptr;
 }
 
-RefPtr<AST::Value> Shell::get_argument(size_t index) const
+RefPtr<AST::Value const> Shell::get_argument(size_t index) const
 {
     if (index == 0)
         return adopt_ref(*new AST::StringValue(current_script));
@@ -369,7 +369,7 @@ RefPtr<AST::Value> Shell::get_argument(size_t index) const
     --index;
     if (auto argv = lookup_local_variable("ARGV"sv)) {
         if (argv->is_list_without_resolution()) {
-            AST::ListValue* list = static_cast<AST::ListValue*>(argv.ptr());
+            AST::ListValue const* list = static_cast<AST::ListValue const*>(argv.ptr());
             if (list->values().size() <= index)
                 return nullptr;
 
@@ -390,7 +390,7 @@ DeprecatedString Shell::local_variable_or(StringView name, DeprecatedString cons
     auto value = lookup_local_variable(name);
     if (value) {
         StringBuilder builder;
-        builder.join(' ', value->resolve_as_list(*this));
+        builder.join(' ', const_cast<AST::Value&>(*value).resolve_as_list(const_cast<Shell&>(*this)));
         return builder.to_deprecated_string();
     }
     return replacement;
@@ -1068,7 +1068,7 @@ bool Shell::is_allowed_to_modify_termios(const AST::Command& command) const
     if (!value)
         return false;
 
-    return value->resolve_as_list(*this).contains_slow(command.argv[0]);
+    return const_cast<AST::Value&>(*value).resolve_as_list(const_cast<Shell&>(*this)).contains_slow(command.argv[0]);
 }
 
 void Shell::restore_ios()
@@ -1093,7 +1093,7 @@ void Shell::block_on_pipeline(RefPtr<AST::Pipeline> pipeline)
 
 void Shell::block_on_job(RefPtr<Job> job)
 {
-    TemporaryChange<Job const*> current_job { m_current_job, job.ptr() };
+    TemporaryChange<Job*> current_job { m_current_job, job.ptr() };
 
     if (!job)
         return;
@@ -1671,7 +1671,7 @@ ErrorOr<Vector<Line::CompletionSuggestion>> Shell::complete_via_program_itself(s
         if (!node)
             return Error::from_string_literal("Cannot complete");
 
-        program_name_storage = node->run(*this)->resolve_as_string(*this);
+        program_name_storage = const_cast<AST::Node&>(*node).run(*this)->resolve_as_string(*this);
         known_program_name = program_name_storage;
     }
 
@@ -2281,7 +2281,7 @@ u64 Shell::find_last_job_id() const
     return job_id;
 }
 
-Job const* Shell::find_job(u64 id, bool is_pid)
+Job* Shell::find_job(u64 id, bool is_pid)
 {
     for (auto& entry : jobs) {
         if (is_pid) {
diff --git a/Userland/Shell/Shell.h b/Userland/Shell/Shell.h
index b1ea7894192..f2912bcaa1e 100644
--- a/Userland/Shell/Shell.h
+++ b/Userland/Shell/Shell.h
@@ -170,8 +170,8 @@ public:
 
     static bool has_history_event(StringView);
 
-    RefPtr<AST::Value> get_argument(size_t) const;
-    RefPtr<AST::Value> lookup_local_variable(StringView) const;
+    RefPtr<AST::Value const> get_argument(size_t) const;
+    RefPtr<AST::Value const> lookup_local_variable(StringView) const;
     DeprecatedString local_variable_or(StringView, DeprecatedString const&) const;
     void set_local_variable(DeprecatedString const&, RefPtr<AST::Value>, bool only_in_current_frame = false);
     void unset_local_variable(StringView, bool only_in_current_frame = false);
@@ -290,8 +290,8 @@ public:
     void restore_ios();
 
     u64 find_last_job_id() const;
-    Job const* find_job(u64 id, bool is_pid = false);
-    Job const* current_job() const { return m_current_job; }
+    Job* find_job(u64 id, bool is_pid = false);
+    Job* current_job() const { return m_current_job; }
     void kill_job(Job const*, int sig);
 
     DeprecatedString get_history_path();
@@ -406,7 +406,7 @@ private:
     void add_entry_to_cache(RunnablePath const&);
     void remove_entry_from_cache(StringView);
     void stop_all_jobs();
-    Job const* m_current_job { nullptr };
+    Job* m_current_job { nullptr };
     LocalFrame* find_frame_containing_local_variable(StringView name);
     LocalFrame const* find_frame_containing_local_variable(StringView name) const
     {