diff --git a/example/composer.json b/example/composer.json
index e262db7..9c3ddb1 100644
--- a/example/composer.json
+++ b/example/composer.json
@@ -1,9 +1,9 @@
 {
   "require": {
-    "slim/slim": "4.7.1",
-    "slim/psr7": "1.3.0",
-    "slim/php-view": "3.0.0",
-    "bryanjhv/slim-session": "4.0",
+    "slim/slim": "4.12.0",
+    "slim/psr7": "1.6.1",
+    "slim/php-view": "3.2.0",
+    "bryanjhv/slim-session": "4.1.2",
     "duosecurity/duo_universal_php": "@dev"
   },
   "repositories": [
diff --git a/example/dockerfile b/example/dockerfile
index 4b63b6c..49cec4a 100644
--- a/example/dockerfile
+++ b/example/dockerfile
@@ -1,9 +1,11 @@
-FROM php:7
+FROM php:8
 EXPOSE 8080
 RUN apt update && apt install -y unzip wget
 WORKDIR /root
 RUN wget https://raw.githubusercontent.com/composer/getcomposer.org/885ece8a6e1370b204b89b7a542169d25aa21177/web/installer -O - -q | php -- --quiet
-ADD . /src
+
+ADD ./composer.json /src/composer.json
 WORKDIR /src
 RUN /root/composer.phar update
+ADD . /src
 ENTRYPOINT ["php", "-S", "0.0.0.0:8080"]
diff --git a/example/index.php b/example/index.php
index f8d4465..fcd0e36 100644
--- a/example/index.php
+++ b/example/index.php
@@ -21,7 +21,7 @@
         $config['api_hostname'],
         $config['redirect_uri'],
         true,
-        $config['http_proxy'],
+        $config['http_proxy'] ?? null,
     );
 } catch (DuoException $e) {
     throw new ErrorException("*** Duo config error. Verify the values in duo.conf are correct ***\n" . $e->getMessage());