diff --git a/FailingNotebook.ipynb b/FailingNotebook.ipynb
new file mode 100644
index 0000000..4ef1f8b
--- /dev/null
+++ b/FailingNotebook.ipynb
@@ -0,0 +1,66 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from ipywidgets import Label, Button, AppLayout, Checkbox, HBox, VBox, Output\n",
+    "\n",
+    "show = Button(description='Click me')\n",
+    "out = Output()\n",
+    "\n",
+    "@out.capture(clear_output=True)\n",
+    "def callback(*args):\n",
+    "    print(args[0])\n",
+    "\n",
+    "class Container(VBox):\n",
+    "    \n",
+    "    def __init__(self, **kwargs):\n",
+    "        self.main = HBox()\n",
+    "        super().__init__(children=[self.main], **kwargs)\n",
+    "        \n",
+    "    def load(self, *args):\n",
+    "        check1 = Checkbox(description=\"test1\")\n",
+    "        check1.observe(callback, 'value')\n",
+    "        check2 = Checkbox(description=\"test2\")\n",
+    "        check2.observe(callback, 'value')\n",
+    "        self.main.children = (check1, check2)\n",
+    "\n",
+    "center = Container()\n",
+    "\n",
+    "show.on_click(center.load)\n",
+    "        \n",
+    "AppLayout(\n",
+    "    header=None,\n",
+    "    left_sidebar=VBox((Label(description=\"hello\"), show, )),\n",
+    "    center=center,\n",
+    "    right_sidebar=None,\n",
+    "    footer=out\n",
+    ")"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python [conda env:voila]",
+   "language": "python",
+   "name": "conda-env-voila-py"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.8.5"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 4
+}
diff --git a/README.md b/README.md
index f11e023..b0a298f 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # voila-material
 
-[![Binder](https://mybinder.org/badge_logo.svg)](https://mybinder.org/v2/gh/voila-dashboards/voila-material/master?urlpath=voila)
+[![Binder](https://mybinder.org/badge_logo.svg)](https://mybinder.org/v2/gh/voila-dashboards/voila-material/stable?urlpath=voila)
 
 Material design template for voila
 
diff --git a/environment.yml b/environment.yml
index 8b45107..70f9cdd 100644
--- a/environment.yml
+++ b/environment.yml
@@ -4,4 +4,5 @@ channels:
 dependencies:
   - ipywidgets=7.5.1
   - bqplot
-  - voila=0.1.12
+  - voila=0.1.21
+  - voila-material=0.3.0
diff --git a/gaussian_process_regression.ipynb b/gaussian_process_regression.ipynb
index 82d565e..76a7c1d 100644
--- a/gaussian_process_regression.ipynb
+++ b/gaussian_process_regression.ipynb
@@ -102,9 +102,7 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "metadata": {
-    "scrolled": true
-   },
+   "metadata": {},
    "outputs": [],
    "source": [
     "fig_margin=dict(top=60, bottom=40, left=50, right=0)\n",
@@ -180,6 +178,35 @@
     "fig.on_displayed(update_reg_line)\n",
     "VBox([fig, VBox(check_boxes + [reset_button])])"
    ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "check_box = Checkbox(description=\"Broken checkbox\")\n",
+    "output = Output()\n",
+    "\n",
+    "@output.capture()\n",
+    "def callback(*args):\n",
+    "    print(\"Called by checkbox\")\n",
+    "\n",
+    "check_box.observe(callback, 'value')\n",
+    "\n",
+    "VBox((check_box, output))"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "@interact(a=True)\n",
+    "def interactive_f(a):\n",
+    "    print(\"Interactive \" + str(a))\n"
+   ]
   }
  ],
  "metadata": {
diff --git a/postBuild b/postBuild
deleted file mode 100644
index 589a374..0000000
--- a/postBuild
+++ /dev/null
@@ -1,2 +0,0 @@
-# Install template
-pip install .