diff --git a/apps/widChargingStatus/dist/widget.js b/apps/widChargingStatus/dist/widget.js
index eea96ce58..6cac1931f 100644
--- a/apps/widChargingStatus/dist/widget.js
+++ b/apps/widChargingStatus/dist/widget.js
@@ -16,14 +16,17 @@
         draw: draw
     };
     Bangle.on('charging', function (charging) {
-        if (charging) {
-            Bangle.buzz();
-            WIDGETS.chargingStatus.width = iconWidth;
+        var widget = WIDGETS.chargingStatus;
+        if (widget) {
+            if (charging) {
+                Bangle.buzz();
+                widget.width = iconWidth;
+            }
+            else {
+                widget.width = 0;
+            }
+            Bangle.drawWidgets(); // re-layout widgets
+            g.flip();
         }
-        else {
-            WIDGETS.chargingStatus.width = 0;
-        }
-        Bangle.drawWidgets(); // re-layout widgets
-        g.flip();
     });
 })();
diff --git a/apps/widChargingStatus/widget.ts b/apps/widChargingStatus/widget.ts
index a8cf2ed94..712bf4f97 100644
--- a/apps/widChargingStatus/widget.ts
+++ b/apps/widChargingStatus/widget.ts
@@ -6,7 +6,7 @@
   );
   const iconWidth = 18;
 
-  function draw() {
+  function draw(this: { x: number; y: number }) {
     g.reset();
     if (Bangle.isCharging()) {
       g.setColor('#FD0');
@@ -19,17 +19,20 @@
   WIDGETS.chargingStatus = {
     area: 'tr',
     width: Bangle.isCharging() ? iconWidth : 0,
-    draw: draw,
+    draw,
   };
 
   Bangle.on('charging', (charging) => {
-    if (charging) {
-      Bangle.buzz();
-      WIDGETS.chargingStatus.width = iconWidth;
-    } else {
-      WIDGETS.chargingStatus.width = 0;
+    const widget = WIDGETS.chargingStatus;
+    if (widget) {
+      if (charging) {
+        Bangle.buzz();
+        widget.width = iconWidth;
+      } else {
+        widget.width = 0;
+      }
+      Bangle.drawWidgets(); // re-layout widgets
+      g.flip();
     }
-    Bangle.drawWidgets(); // re-layout widgets
-    g.flip();
   });
 })();
diff --git a/typescript/tsconfig.json b/typescript/tsconfig.json
index 8a7ab3342..09101094b 100644
--- a/typescript/tsconfig.json
+++ b/typescript/tsconfig.json
@@ -2,7 +2,16 @@
   "compilerOptions": {
     "module": "es2015",
     "noImplicitAny": true,
-    "target": "es2015"
+    "target": "es2015",
+    "allowUnreachableCode": false,
+    "allowUnusedLabels": false,
+    "noImplicitOverride": true,
+    "noImplicitReturns": true,
+    "noImplicitThis": true,
+    "noUncheckedIndexedAccess": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true,
+    "strict": true
   },
   "include": ["../apps/**/*", "./**/*"]
 }
diff --git a/typescript/types/globals.d.ts b/typescript/types/globals.d.ts
index 359d5d294..46d1e3b0a 100644
--- a/typescript/types/globals.d.ts
+++ b/typescript/types/globals.d.ts
@@ -178,6 +178,6 @@ declare const g: GraphicsApi;
 declare type Widget = {
   area: 'tr' | 'tl';
   width: number;
-  draw: () => void;
+  draw: (this: { x: number; y: number }) => void;
 };
 declare const WIDGETS: { [key: string]: Widget };