diff --git a/CHANGELOG.md b/CHANGELOG.md
index deb579d..94fa334 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,9 @@
 - [ ] add module to check directory structure
 - [ ] add DA badge to module _gitshields_
 
+0.1.1
+- fix php < 8.0
+
 0.1 - 2021.09.11
 - First release
 
diff --git a/inc/class.improve.action.php b/inc/class.improve.action.php
index 919bbae..4856ddb 100644
--- a/inc/class.improve.action.php
+++ b/inc/class.improve.action.php
@@ -72,17 +72,17 @@ abstract class ImproveAction
         return self::$notice[get_called_class()][$error ? 'error' : 'warning'];
     }
 
-    final public function __get(string $property): mixed
+    final public function __get(string $property)
     {
         return $this->getProperty($property);
     }
 
-    final public function getProperty(string $property): mixed
+    final public function getProperty(string $property)
     {
         return $this->properties[$property] ?? null;
     }
 
-    final protected function setProperties(mixed $property, mixed $value = null): bool
+    final protected function setProperties($property, $value = null): bool
     {
         $properties = is_array($property) ? $property : [$property => $value];
         foreach($properties as $k => $v) {
@@ -96,12 +96,12 @@ abstract class ImproveAction
         return true;
     }
 
-    final protected function getPreference(string $preference): mixed
+    final protected function getPreference(string $preference)
     {
         return $this->preferences[$preference] ?? null;
     }
 
-    final protected function setPreferences(mixed $preference, mixed $value = null)
+    final protected function setPreferences $preference, $value = null)
     {
         $preferences = is_array($preference) ? $preference : [$preference => $value];
         foreach($preferences as $k => $v) {
@@ -131,7 +131,7 @@ abstract class ImproveAction
 
     public static function create(arrayObject $o, dcCore $core)
     {
-        $o->append(new (get_called_class())($core));
+        $o->append(new ${get_called_class()}($core));
     }
 
     public function configure(string $redirect_url): ?string
diff --git a/inc/class.improve.php b/inc/class.improve.php
index 5aa52a4..f6af4a1 100644
--- a/inc/class.improve.php
+++ b/inc/class.improve.php
@@ -167,7 +167,7 @@ class Improve
         return $this->core->adminurl->get('admin.plugin.improve', $params);
     }
 
-    public static function cleanExtensions(mixed $in): array
+    public static function cleanExtensions($in): array
     {
         $out = [];
         if (!is_array($in)) {