diff --git a/Userland/DevTools/HackStudio/EditorWrapper.h b/Userland/DevTools/HackStudio/EditorWrapper.h
index ea72912180..5493be746e 100644
--- a/Userland/DevTools/HackStudio/EditorWrapper.h
+++ b/Userland/DevTools/HackStudio/EditorWrapper.h
@@ -37,7 +37,8 @@ public:
     void set_mode_displayable();
     void set_mode_non_displayable();
     void set_filename(const String&);
-    const String& filename() const {return m_filename;}
+    const String& filename() const { return m_filename; }
+    bool document_dirty() const { return m_document_dirty; }
 
 private:
     EditorWrapper();
@@ -48,7 +49,7 @@ private:
     RefPtr<GUI::Label> m_filename_label;
     RefPtr<GUI::Label> m_cursor_label;
     RefPtr<Editor> m_editor;
-    bool m_document_dirty {false};
+    bool m_document_dirty { false };
 };
 
 }
diff --git a/Userland/DevTools/HackStudio/HackStudioWidget.cpp b/Userland/DevTools/HackStudio/HackStudioWidget.cpp
index 5f7f0e5d32..5082480f96 100644
--- a/Userland/DevTools/HackStudio/HackStudioWidget.cpp
+++ b/Userland/DevTools/HackStudio/HackStudioWidget.cpp
@@ -896,6 +896,9 @@ void HackStudioWidget::create_toolbar(GUI::Widget& parent)
 NonnullRefPtr<GUI::Action> HackStudioWidget::create_build_action()
 {
     return GUI::Action::create("&Build", { Mod_Ctrl, Key_B }, Gfx::Bitmap::load_from_file("/res/icons/16x16/build.png"), [this](auto&) {
+        if (warn_unsaved_changes("There are unsaved changes, do you want to save before building?") == ContinueDecision::No)
+            return;
+
         reveal_action_tab(*m_terminal_wrapper);
         build(*m_terminal_wrapper);
         m_stop_action->set_enabled(true);
@@ -1129,4 +1132,35 @@ HackStudioWidget::~HackStudioWidget()
     }
 }
 
+HackStudioWidget::ContinueDecision HackStudioWidget::warn_unsaved_changes(const String& prompt)
+{
+    if (!any_document_is_dirty())
+        return ContinueDecision::Yes;
+
+    auto result = GUI::MessageBox::show(window(), prompt, "Unsaved changes", GUI::MessageBox::Type::Warning, GUI::MessageBox::InputType::YesNoCancel);
+
+    if (result == GUI::MessageBox::ExecCancel)
+        return ContinueDecision::No;
+
+    if (result == GUI::MessageBox::ExecYes) {
+        for (auto& editor_wrapper : m_all_editor_wrappers) {
+            if (editor_wrapper.document_dirty()) {
+                editor_wrapper.save();
+            }
+        }
+    }
+
+    return ContinueDecision::Yes;
+}
+
+bool HackStudioWidget::any_document_is_dirty() const
+{
+    for (auto& editor_wrapper : m_all_editor_wrappers) {
+        if (editor_wrapper.document_dirty()) {
+            return true;
+        }
+    }
+    return false;
+}
+
 }
diff --git a/Userland/DevTools/HackStudio/HackStudioWidget.h b/Userland/DevTools/HackStudio/HackStudioWidget.h
index 5d386712fa..be71cd480b 100644
--- a/Userland/DevTools/HackStudio/HackStudioWidget.h
+++ b/Userland/DevTools/HackStudio/HackStudioWidget.h
@@ -50,6 +50,12 @@ public:
         return *m_locator;
     }
 
+    enum class ContinueDecision {
+        No,
+        Yes
+    };
+    ContinueDecision warn_unsaved_changes(const String& prompt);
+
 private:
     static String get_full_path_of_serenity_source(const String& file);
     Vector<String> selected_file_paths() const;
@@ -112,6 +118,7 @@ private:
     void build(TerminalWrapper& wrapper);
 
     void hide_action_tabs();
+    bool any_document_is_dirty() const;
 
     NonnullRefPtrVector<EditorWrapper> m_all_editor_wrappers;
     RefPtr<EditorWrapper> m_current_editor_wrapper;
diff --git a/Userland/DevTools/HackStudio/main.cpp b/Userland/DevTools/HackStudio/main.cpp
index 0cb393c89b..cea0bda219 100644
--- a/Userland/DevTools/HackStudio/main.cpp
+++ b/Userland/DevTools/HackStudio/main.cpp
@@ -81,6 +81,12 @@ int main(int argc, char** argv)
     s_hack_studio_widget->initialize_menubar(menubar);
     s_window->set_menubar(menubar);
 
+    s_window->on_close_request = [&]() -> GUI::Window::CloseRequestDecision {
+        if (s_hack_studio_widget->warn_unsaved_changes("There are unsaved changes, do you want to save before exiting?") == HackStudioWidget::ContinueDecision::Yes)
+            return GUI::Window::CloseRequestDecision::Close;
+        return GUI::Window::CloseRequestDecision::StayOpen;
+    };
+
     s_window->show();
 
     s_hack_studio_widget->update_actions();