diff --git a/src/Previewer/DBusPreviewer.js b/src/Previewer/DBusPreviewer.js
index d56e9f891..cf2e35d41 100644
--- a/src/Previewer/DBusPreviewer.js
+++ b/src/Previewer/DBusPreviewer.js
@@ -42,6 +42,11 @@ async function startProcess(type) {
     [executable_name, server.get_client_address()],
     Gio.SubprocessFlags.NONE,
   );
+
+  current_sub_process.wait_async(null).then(() => {
+    dbus_previewer.onStop?.();
+  });
+
   current_type = type;
 
   const connection = await new Promise((resolve) => {
@@ -83,12 +88,14 @@ async function startProcess(type) {
     null,
   );
 
-  proxy.connectSignal("CssParserError", (_proxy, _name_owner, ...args) => {
+  proxy.connectSignal("CssParserError", (_self, _name_owner, ...args) => {
     dbus_previewer.onCssParserError?.(...args);
   });
 
-  proxy.connectSignal("WindowOpen", (_proxy, _name_owner, ...args) => {
-    dbus_previewer.onWindowOpen?.(...args);
+  proxy.connectSignal("WindowOpen", (_self, _name_owner, [open]) => {
+    if (!open) {
+      dbus_previewer.stop().catch(console.error);
+    }
   });
 
   return proxy;
@@ -96,7 +103,7 @@ async function startProcess(type) {
 
 const dbus_previewer = {
   onCssParserError: null, // set in External.js
-  onWindowOpen: null, // set in External.js
+  onStop: null,
   async getProxy(type) {
     if (current_type !== type) {
       await this.stop();
diff --git a/src/Previewer/External.js b/src/Previewer/External.js
index a85b9618b..6f124e16e 100644
--- a/src/Previewer/External.js
+++ b/src/Previewer/External.js
@@ -1,13 +1,11 @@
 import Adw from "gi://Adw";
 import dbus_previewer from "./DBusPreviewer.js";
 
-export default function External({ output, builder, onWindowChange }) {
+export default function External({ output, builder, onStop }) {
   const stack = builder.get_object("stack_preview");
   let dbus_proxy;
 
-  dbus_previewer.onWindowOpen = ([open]) => {
-    onWindowChange(open);
-  };
+  dbus_previewer.onStop = onStop;
 
   dbus_previewer.onCssParserError = (error) => {
     builder
@@ -46,15 +44,10 @@ export default function External({ output, builder, onWindowChange }) {
       console.debug(err);
       return;
     }
-    stack.set_visible_child_name("open_window");
   }
 
   function stop() {
-    close()
-      .then(() => {
-        return dbus_previewer.stop();
-      })
-      .catch(console.error);
+    close().then(() => dbus_previewer.stop());
   }
 
   async function updateXML({ xml, target_id, original_id }) {
diff --git a/src/Previewer/Internal.js b/src/Previewer/Internal.js
index faedf2e90..ca5faef04 100644
--- a/src/Previewer/Internal.js
+++ b/src/Previewer/Internal.js
@@ -19,6 +19,7 @@ export default function Internal({
   dropdown_preview_align,
   panel_ui,
   session,
+  onStop,
 }) {
   const inline_css_scope_target = output.get_parent();
   inline_css_scope_target.name = `workbench_output-${session.id}`;
@@ -51,12 +52,8 @@ export default function Internal({
     onWindowChange(true);
   }
 
-  async function close() {
-    object_root?.close();
-  }
-
   function stop() {
-    close();
+    object_root?.close();
     if (css_provider) {
       Gtk.StyleContext.remove_provider_for_display(
         output.get_display(),
@@ -66,6 +63,7 @@ export default function Internal({
     }
     object_root?.destroy();
     object_root = null;
+    onStop();
   }
 
   function preview(object) {
@@ -230,7 +228,6 @@ export default function Internal({
   return {
     async start(_language) {},
     open,
-    close,
     stop,
     updateXML,
     updateCSS,
diff --git a/src/Previewer/Previewer.js b/src/Previewer/Previewer.js
index 992012e72..b909f5661 100644
--- a/src/Previewer/Previewer.js
+++ b/src/Previewer/Previewer.js
@@ -51,13 +51,10 @@ export default function Previewer({
   makeDropdownFlat(dropdown_preview_align);
 
   const internal = Internal({
-    onWindowChange(open) {
-      if (current !== internal) return;
-      if (open) {
-        stack.set_visible_child_name("close_window");
-      } else {
-        stack.set_visible_child_name("open_window");
-      }
+    onStop() {
+      console.log("stopping ouin ouin internal");
+      stack_start_stop.visible_child = button_run;
+      update(true);
     },
     output,
     builder,
@@ -67,15 +64,16 @@ export default function Previewer({
     panel_ui,
     session,
   });
+
+  const stack_start_stop = builder.get_object("stack_start_stop");
+  const button_run = builder.get_object("button_run");
+  // const button_stop = builder.get_object("button_stop");
+
   const external = External({
-    onWindowChange(open) {
-      if (current !== external) return;
-      if (open) {
-        stack.set_visible_child_name("close_window");
-      } else {
-        stack.set_visible_child_name("open_window");
-        useInternal().catch(console.error);
-      }
+    onStop() {
+      console.log("stoping ouin ouin external");
+      stack_start_stop.visible_child = button_run;
+      useInternal().catch(console.error);
     },
     output,
     builder,
@@ -87,12 +85,6 @@ export default function Previewer({
 
   let handler_id_ui = null;
   let handler_id_css = null;
-  let handler_id_button_open;
-  let handler_id_button_close;
-
-  const stack = builder.get_object("stack_preview");
-  const button_open = builder.get_object("button_open_preview_window");
-  const button_close = builder.get_object("button_close_preview_window");
 
   settings.bind(
     "preview-align",
@@ -109,8 +101,19 @@ export default function Previewer({
   }
   setPreviewAlign();
 
+  function clean() {
+    if (handler_id_ui) {
+      panel_ui.disconnect(handler_id_ui);
+      handler_id_ui = null;
+    }
+    if (handler_id_css) {
+      code_view_css.disconnect(handler_id_css);
+      handler_id_css = null;
+    }
+  }
+
   function start() {
-    stop();
+    clean();
     if (handler_id_ui === null) {
       handler_id_ui = panel_ui.connect("updated", () => schedule_update());
     }
@@ -122,14 +125,9 @@ export default function Previewer({
   }
 
   function stop() {
-    if (handler_id_ui) {
-      panel_ui.disconnect(handler_id_ui);
-      handler_id_ui = null;
-    }
-    if (handler_id_css) {
-      code_view_css.disconnect(handler_id_css);
-      handler_id_css = null;
-    }
+    console.log("previewer stop");
+    clean();
+    current?.stop?.();
   }
 
   // Using this custom scope we make sure that previewing UI definitions
@@ -243,7 +241,6 @@ export default function Previewer({
       await setPreviewer(external, language);
     }
     current_external_language = language;
-    stack.set_visible_child_name("close_window");
     await update(true);
   }
 
@@ -255,13 +252,6 @@ export default function Previewer({
   }
 
   async function setPreviewer(previewer, language) {
-    if (handler_id_button_open) {
-      button_open.disconnect(handler_id_button_open);
-    }
-    if (handler_id_button_close) {
-      button_close.disconnect(handler_id_button_close);
-    }
-
     try {
       await current?.closeInspector();
     } catch {
@@ -275,25 +265,6 @@ export default function Previewer({
     }
 
     current = previewer;
-
-    handler_id_button_open = button_open.connect("clicked", async () => {
-      try {
-        await current.open();
-        stack.set_visible_child_name("close_window");
-      } catch (err) {
-        console.error(err);
-      }
-    });
-
-    handler_id_button_close = button_close.connect("clicked", async () => {
-      try {
-        await current.close();
-        stack.set_visible_child_name("open_window");
-      } catch (err) {
-        console.error(err);
-      }
-    });
-
     try {
       await current.start(language);
     } catch (err) {
@@ -315,9 +286,6 @@ export default function Previewer({
     open() {
       return current.open();
     },
-    close() {
-      return current.close();
-    },
     openInspector() {
       return current.openInspector();
     },
diff --git a/src/langs/rust/Compiler.js b/src/langs/rust/Compiler.js
index 4f479b414..103c5ce8b 100644
--- a/src/langs/rust/Compiler.js
+++ b/src/langs/rust/Compiler.js
@@ -43,8 +43,10 @@ export default function Compiler({ session }) {
   async function run() {
     try {
       const proxy = await dbus_previewer.getProxy("vala"); // rust uses the Vala previewer.
-      const sharedLibrary = `${targetPath}/debug/libdemo.so`;
-      await proxy.RunAsync(sharedLibrary, session.file.get_uri());
+      await proxy.RunAsync(
+        `${targetPath}/debug/libdemo.so`,
+        session.file.get_uri(),
+      );
     } catch (err) {
       console.error(err);
       return false;
diff --git a/src/window.blp b/src/window.blp
index 79cacde91..2bbdac4ee 100644
--- a/src/window.blp
+++ b/src/window.blp
@@ -121,19 +121,33 @@ Adw.ApplicationWindow window {
       }
 
       [end]
-      Button button_run {
-        child: Adw.ButtonContent {
-          icon-name: "media-playback-start-symbolic";
-          label: _("_Run");
-          use-underline: true;
-        };
+      Stack stack_start_stop {
+        Button button_run {
+          child: Adw.ButtonContent {
+            icon-name: "media-playback-start-symbolic";
+            label: _("_Run");
+            use-underline: true;
+          };
 
-        action-name: "win.run";
-        tooltip-text: _("Run (Ctrl+⏎)");
+          action-name: "win.run";
+          tooltip-text: _("Run (Ctrl+⏎)");
 
-        styles [
-          "suggested-action"
-        ]
+          styles [
+            "suggested-action"
+          ]
+        }
+
+        Button button_stop {
+          child: Adw.ButtonContent {
+            icon-name: "media-playback-stop-symbolic";
+            label: _("_Stop");
+            use-underline: true;
+          };
+
+          styles [
+            "suggested-action"
+          ]
+        }
       }
     }
 
@@ -417,19 +431,16 @@ Adw.ApplicationWindow window {
                   title: _("Windowed Preview");
                   description: _("This interface can only be previewed as a separate window.\nWe recommend using “Always on Top”.");
                   icon-name: "multitasking-windows-symbolic";
-
-                  Box {
-                    halign: center;
-
-                    Button button_open_preview_window {
-                      label: _("Show Preview Window");
-
-                      styles [
-                        "pill",
-                        "suggested-action"
-                      ]
-                    }
-                  }
+                  // Box {
+                  //   halign: center;
+                  //   Button button_open_preview_window {
+                  //     label: _("Show Preview Window");
+                  //     styles [
+                  //       "pill",
+                  //       "suggested-action"
+                  //     ]
+                  //   }
+                  // }
                 };
               }
 
@@ -440,18 +451,15 @@ Adw.ApplicationWindow window {
                   title: _("Windowed Preview");
                   description: _("This interface can only be previewed as a separate window.\nWe recommend using “Always on Top”.");
                   icon-name: "multitasking-windows-symbolic";
-
-                  Box {
-                    halign: center;
-
-                    Button button_close_preview_window {
-                      label: _("Close Preview Window");
-
-                      styles [
-                        "pill"
-                      ]
-                    }
-                  }
+                  // Box {
+                  //   halign: center;
+                  //   Button button_close_preview_window {
+                  //     label: _("Close Preview Window");
+                  //     styles [
+                  //       "pill"
+                  //     ]
+                  //   }
+                  // }
                 };
               }
             }
diff --git a/src/window.js b/src/window.js
index 40104211c..c813fe755 100644
--- a/src/window.js
+++ b/src/window.js
@@ -158,7 +158,9 @@ export default function Window({ application, session }) {
 
   previewer.setPanelCode(panel_code);
 
-  const button_run = builder.get_object("button_run");
+  const stack_start_stop = builder.get_object("stack_start_stop");
+  // const button_run = builder.get_object("button_run");
+  const button_stop = builder.get_object("button_stop");
   const button_preview = builder.get_object("button_preview");
   const button_inspector = builder.get_object("button_inspector");
 
@@ -230,8 +232,6 @@ export default function Window({ application, session }) {
   let builder_python = null;
 
   async function runCode({ format }) {
-    button_run.set_sensitive(false);
-
     term_console.clear();
     previewer.stop();
     panel_ui.stop();
@@ -243,7 +243,7 @@ export default function Window({ application, session }) {
         await formatCode();
       }
 
-      await compile();
+      await start();
     } catch (err) {
       // prettier xml errors are not instances of Error
       if (err instanceof Error || err instanceof GLib.Error) {
@@ -256,11 +256,10 @@ export default function Window({ application, session }) {
     previewer.start();
     panel_ui.start();
 
-    button_run.set_sensitive(true);
     term_console.scrollToEnd();
   }
 
-  async function compile() {
+  async function start() {
     const { language } = panel_code;
 
     const lang = langs[language.toLowerCase()];
@@ -270,6 +269,8 @@ export default function Window({ application, session }) {
       return;
     }
 
+    stack_start_stop.visible_child = button_stop;
+
     if (language === "JavaScript") {
       await previewer.update(true);
 
@@ -307,10 +308,14 @@ export default function Window({ application, session }) {
       compiler_vala = compiler_vala || ValaCompiler({ session });
       const success = await compiler_vala.compile();
       if (success) {
+        console.log("use external");
         await previewer.useExternal("vala");
+        console.log("run");
         if (await compiler_vala.run()) {
+          console.log("open");
           await previewer.open();
         } else {
+          console.log("use internal");
           await previewer.useInternal();
         }
       }
@@ -350,6 +355,10 @@ export default function Window({ application, session }) {
   window.add_action(action_run);
   application.set_accels_for_action("win.run", ["<Control>Return"]);
 
+  button_stop.connect("clicked", () => {
+    previewer.stop();
+  });
+
   const action_format = new Gio.SimpleAction({
     name: "format",
   });