diff --git a/src/ide/views/visuals.ts b/src/ide/views/visuals.ts
new file mode 100644
index 00000000..9f3d9669
--- /dev/null
+++ b/src/ide/views/visuals.ts
@@ -0,0 +1,215 @@
+
+import { errorMarkers } from "./gutter";
+
+import { StateEffect, StateField } from "@codemirror/state";
+import { Decoration, DecorationSet, EditorView, WidgetType } from "@codemirror/view";
+
+// Highlight program counter line.
+const currentPcEffect = StateEffect.define<number | null>();
+
+const currentPcDecoration = Decoration.line({
+  attributes: { class: "cm-currentpc" }
+});
+
+const currentPcLineField = StateField.define({
+  create() { return Decoration.none },
+  update(lines, tr) {
+    lines = lines.map(tr.changes)
+
+    for (let e of tr.effects) {
+      if (e.is(currentPcEffect)) {
+        if (e.value === null) return Decoration.none;
+
+        const line = tr.state.doc.line(e.value);
+        return Decoration.set([currentPcDecoration.range(line.from)]);
+      }
+    }
+    return lines;
+  },
+  provide: f => EditorView.decorations.from(f),
+});
+
+
+// Error message widget to show below error lines
+class ErrorMessageWidget extends WidgetType {
+  constructor(readonly message: string) { super() }
+
+  toDOM() {
+    let div = document.createElement("div");
+    div.textContent = this.message;
+    div.style.cssText = `
+      color: #ff6666;
+      background-color: #330000;
+      padding: 4px 8px;
+      margin: 2px 0;
+      border-left: 3px solid #ff0000;
+      font-family: monospace;
+    `;
+    return div;
+  }
+}
+
+// State field to manage error message decorations (supports multiple messages)
+const errorMessageField = StateField.define<DecorationSet>({
+  create() { return Decoration.none; },
+  update(decorations, tr) {
+    // Map existing decorations across document changes
+    decorations = decorations.map(tr.changes);
+
+    for (let e of tr.effects) {
+      if (e.is(errorMarkers.showMessage)) {
+        if (e.value === null || !e.value) {
+          // Clear all messages
+          return Decoration.none;
+        } else if (e.value.toggle) {
+          // Build new decoration set with toggled message
+          const widgets: any[] = [];
+
+          // Collect existing decorations
+          const existingMessages = new Map<number, string>();
+          decorations.between(0, tr.state.doc.length, (from, to, value) => {
+            try {
+              const lineNum = tr.state.doc.lineAt(to).number;
+              if (value.spec.widget instanceof ErrorMessageWidget) {
+                existingMessages.set(lineNum, (value.spec.widget as ErrorMessageWidget).message);
+              }
+            } catch { }
+          });
+
+          // Check if we're adding or removing this line's message
+          const isCurrentlyShown = existingMessages.has(e.value.line);
+
+          if (isCurrentlyShown) {
+            // Remove the message
+            existingMessages.delete(e.value.line);
+          } else {
+            // Add the new message
+            existingMessages.set(e.value.line, e.value.msg);
+          }
+
+          // Build sorted decorations
+          const sortedLines = Array.from(existingMessages.keys()).sort((a, b) => a - b);
+          sortedLines.forEach(lineNum => {
+            try {
+              const line = tr.state.doc.line(lineNum);
+              widgets.push(
+                Decoration.widget({
+                  widget: new ErrorMessageWidget(existingMessages.get(lineNum)!),
+                  block: true,
+                  side: 1
+                }).range(line.to)
+              );
+            } catch {
+              // Line doesn't exist, skip
+            }
+          });
+
+          return Decoration.set(widgets, true);
+        }
+      }
+    }
+    return decorations;
+  },
+  provide: f => EditorView.decorations.from(f),
+});
+
+// Decorator widget to show values.
+class ShowValueWidget extends WidgetType {
+  constructor(readonly value: string) { super() }
+
+  toDOM() {
+    let div = document.createElement("div");
+    div.textContent = `${this.value}`;
+    div.style.cssText = `
+      color: #ccccff;
+      background-color: #000066;
+      display: inline-block;
+    `;
+    div.className = "cm-line";
+    return div
+  }
+}
+
+// Effect to pass the position and value to the state.
+const showValueEffect = StateEffect.define<{ pos: number, val: any } | null>();
+
+const showValueDecorationField = StateField.define({
+  create() { return Decoration.none },
+  update(decorations, tr) {
+    decorations = decorations.map(tr.changes);
+
+    for (let e of tr.effects) {
+      if (e.is(showValueEffect)) {
+        if (e.value === null || !e.value) {
+          return Decoration.none;
+        }
+        return Decoration.set([
+          Decoration.widget({
+            widget: new ShowValueWidget(e.value.val),
+            block: true,
+            side: 1 // Appears after the text
+          }).range(e.value.pos)
+        ])
+      }
+    }
+    return decorations;
+  },
+  provide: f => EditorView.decorations.from(f),
+});
+
+const highlightLinesEffect = StateEffect.define<{ start: number, end: number } | null>();
+
+const highlightLinesDecoration = Decoration.line({
+  attributes: { class: "highlight-lines" }
+});
+
+const highlightLinesField = StateField.define({
+  create() { return Decoration.none },
+  update(decorations, tr) {
+    decorations = decorations.map(tr.changes);
+
+    for (let e of tr.effects) {
+      if (e.is(highlightLinesEffect)) {
+        if (e.value === null) return Decoration.none;
+
+        const { start, end } = e.value;
+        const decorationRanges: any[] = [];
+
+        // Highlight all lines in the range
+        for (let lineNum = start; lineNum <= end; lineNum++) {
+          try {
+            const line = tr.state.doc.line(lineNum);
+            decorationRanges.push(highlightLinesDecoration.range(line.from));
+          } catch {
+            // Line doesn't exist, skip
+          }
+        }
+
+        return Decoration.set(decorationRanges);
+      }
+    }
+    return decorations;
+  },
+  provide: f => EditorView.decorations.from(f),
+});
+
+export const errorMessages = {
+  field: errorMessageField,
+  widget: ErrorMessageWidget,
+};
+
+export const currentPc = {
+  effect: currentPcEffect,
+  decoration: currentPcDecoration,
+  field: currentPcLineField,
+};
+
+export const showValue = {
+  effect: showValueEffect,
+  field: showValueDecorationField,
+};
+
+export const highlightLines = {
+  effect: highlightLinesEffect,
+  field: highlightLinesField,
+};