diff --git a/src/API.ts b/src/API.ts
index 5e7c3e9..cdb932a 100644
--- a/src/API.ts
+++ b/src/API.ts
@@ -18,6 +18,7 @@ const sound = (value: any) => ({
 export class UserAPI {
 
     variables: { [key: string]: any } = {}
+    iterators: { [key: string]: any } = {}
     MidiConnection: MidiConnection = new MidiConnection()
     strudelSound = webaudioOutput()
     load: samples
@@ -100,6 +101,34 @@ export class UserAPI {
         this.MidiConnection.panic()
     }
 
+    // =============================================================
+    // Iterator related functions
+    // =============================================================
+
+    public iterator(name: string, limit?: number, step?: number) {
+        // Check if iterator already exists
+        if (!(name in this.iterators)) {
+            // Create new iterator with default step of 1
+            this.iterators[name] = {
+                value: 0,
+                step: step ?? 1,
+                limit
+            };
+        } else {
+            // Increment existing iterator by step value
+            this.iterators[name].value += this.iterators[name].step;
+
+            // Check for limit overshoot
+            if (this.iterators[name].limit !== undefined &&
+                this.iterators[name].value > this.iterators[name].limit) {
+                this.iterators[name].value = 0;
+            }
+        }
+
+        // Return current iterator value
+        return this.iterators[name].value;
+    }
+
     // =============================================================
     // Variable related functions
     // =============================================================
diff --git a/src/main.ts b/src/main.ts
index 79c89db..c9b25e7 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -208,6 +208,7 @@ export class Editor {
         event.preventDefault();
         // const code = this.getCodeBlock();
         this.currentFile.candidate = this.view.state.doc.toString();
+        this.flashBackground('#2d313d', 200)
         // tryEvaluate(this, this.currentFile);
       }
 
@@ -218,6 +219,7 @@ export class Editor {
       ) {
         event.preventDefault(); // Prevents the addition of a new line
         this.currentFile.candidate = this.view.state.doc.toString();
+        this.flashBackground('#2d313d', 200)
         // const code = this.getSelectedLines();
       }
 
@@ -413,8 +415,6 @@ export class Editor {
         if (svg.classList.contains("text-orange-300")) {
           svg.classList.remove("text-orange-300");
           button.classList.remove("text-orange-300");
-          console.log(svg.classList)
-          console.log(button.classList)
         }
       });
       button.children[0].classList.remove('text-white');
@@ -499,11 +499,7 @@ export class Editor {
   updateEditorView(): void {
     // Remove everything from the editor
     this.view.dispatch({
-      changes: {
-        from: 0,
-        to: this.view.state.doc.toString().length,
-        insert: "",
-      },
+      changes: { from: 0, to: this.view.state.doc.toString().length, insert: '', },
     });
 
     // Insert something
@@ -653,6 +649,22 @@ export class Editor {
     document.getElementById("modal")!.classList.add("invisible");
     document.getElementById("modal-buffers")!.classList.add("invisible");
   }
+
+  flashBackground(color: string, duration: number) {
+    // Set the flashing color
+    this.view.dom.style.backgroundColor = color;
+    const gutters = this.view.dom.getElementsByClassName("cm-gutter");
+    Array.from(gutters).forEach(gutter => gutter.style.backgroundColor = color);
+  
+    // Reset to original color after duration
+    setTimeout(() => {
+      this.view.dom.style.backgroundColor = "";
+      Array.from(gutters).forEach(gutter => gutter.style.backgroundColor = "");
+    }, duration);
+  }
+
+
+
 }
 
 const app = new Editor();
@@ -682,10 +694,10 @@ document.getElementById("start-button")!.addEventListener("click", startClock);
 // When the user leaves the page, all the universes should be saved in the localStorage
 window.addEventListener("beforeunload", () => {
   event.preventDefault();
-  event.returnValue = "";
   // Iterate over all local files and set the candidate to the committed
   app.currentFile.candidate = app.view.state.doc.toString();
   app.currentFile.committed = app.view.state.doc.toString();
   app.settings.saveApplicationToLocalStorage(app.universes, app.settings);
   app.clock.stop()
+  return null;
 });