diff --git a/lib/AbstractPicoPlugin.php b/lib/AbstractPicoPlugin.php
index 250d757..92b8d91 100644
--- a/lib/AbstractPicoPlugin.php
+++ b/lib/AbstractPicoPlugin.php
@@ -110,7 +110,7 @@ abstract class AbstractPicoPlugin implements PicoPluginInterface
      */
     protected function configEnabled()
     {
-        $pluginEnabled = $this->getPico()->getConfig(get_called_class() . '.enabled');
+        $pluginEnabled = $this->getPico()->getConfig(static::class . '.enabled');
         if ($pluginEnabled !== null) {
             $this->setEnabled($pluginEnabled);
         } else {
@@ -186,7 +186,7 @@ abstract class AbstractPicoPlugin implements PicoPluginInterface
      */
     public function getPluginConfig($configName = null, $default = null)
     {
-        $pluginConfig = $this->getPico()->getConfig(get_called_class(), []);
+        $pluginConfig = $this->getPico()->getConfig(static::class, []);
 
         if ($configName === null) {
             return $pluginConfig;
@@ -215,7 +215,7 @@ abstract class AbstractPicoPlugin implements PicoPluginInterface
 
         throw new BadMethodCallException(
             'Call to undefined method ' . get_class($this->getPico()) . '::' . $methodName . '() '
-            . 'through ' . get_called_class() . '::__call()'
+            . 'through ' . static::class . '::__call()'
         );
     }
 
@@ -235,7 +235,7 @@ abstract class AbstractPicoPlugin implements PicoPluginInterface
                 $plugin = $this->getPico()->getPlugin($pluginName);
             } catch (RuntimeException $e) {
                 throw new RuntimeException(
-                    "Unable to enable plugin '" . get_called_class() . "': "
+                    "Unable to enable plugin '" . static::class . "': "
                     . "Required plugin '" . $pluginName . "' not found"
                 );
             }
@@ -247,13 +247,13 @@ abstract class AbstractPicoPlugin implements PicoPluginInterface
                         $plugin->setEnabled(true, true, true);
                     } else {
                         throw new RuntimeException(
-                            "Unable to enable plugin '" . get_called_class() . "': "
+                            "Unable to enable plugin '" . static::class . "': "
                             . "Required plugin '" . $pluginName . "' was disabled manually"
                         );
                     }
                 } else {
                     throw new RuntimeException(
-                        "Unable to enable plugin '" . get_called_class() . "': "
+                        "Unable to enable plugin '" . static::class . "': "
                         . "Required plugin '" . $pluginName . "' is disabled"
                     );
                 }
@@ -289,7 +289,7 @@ abstract class AbstractPicoPlugin implements PicoPluginInterface
                             $plugin->setEnabled(false, true, true);
                         } else {
                             throw new RuntimeException(
-                                "Unable to disable plugin '" . get_called_class() . "': "
+                                "Unable to disable plugin '" . static::class . "': "
                                 . "Required by manually enabled plugin '" . $pluginName . "'"
                             );
                         }
@@ -299,7 +299,7 @@ abstract class AbstractPicoPlugin implements PicoPluginInterface
                 $dependantsList = 'plugin' . ((count($dependants) > 1) ? 's' : '') . ' '
                     . "'" . implode("', '", array_keys($dependants)) . "'";
                 throw new RuntimeException(
-                    "Unable to disable plugin '" . get_called_class() . "': "
+                    "Unable to disable plugin '" . static::class . "': "
                     . "Required by " . $dependantsList
                 );
             }
@@ -317,7 +317,7 @@ abstract class AbstractPicoPlugin implements PicoPluginInterface
                 // only plugins which implement PicoPluginInterface support dependencies
                 if ($plugin instanceof PicoPluginInterface) {
                     $dependencies = $plugin->getDependencies();
-                    if (in_array(get_called_class(), $dependencies)) {
+                    if (in_array(static::class, $dependencies)) {
                         $this->dependants[$pluginName] = $plugin;
                     }
                 }
@@ -351,7 +351,7 @@ abstract class AbstractPicoPlugin implements PicoPluginInterface
 
             if (!$this->nativePlugin && ($pluginApiVersion > $picoApiVersion)) {
                 throw new RuntimeException(
-                    "Unable to enable plugin '" . get_called_class() . "': The plugin's API (version "
+                    "Unable to enable plugin '" . static::class . "': The plugin's API (version "
                     . $pluginApiVersion . ") isn't compatible with Pico's API (version " . $picoApiVersion . ")"
                 );
             }
diff --git a/lib/Pico.php b/lib/Pico.php
index 9b24722..3fa5bdd 100644
--- a/lib/Pico.php
+++ b/lib/Pico.php
@@ -575,7 +575,7 @@ class Pico
 
         if (!isset($this->plugins['PicoDeprecated']) && (count($this->plugins) !== count($this->nativePlugins))) {
             throw new RuntimeException(
-                "Plugins using an older API than version " . static::API_VERSION . " found, "
+                "Plugins using an older API than version " . self::API_VERSION . " found, "
                 . "but PicoDeprecated isn't loaded"
             );
         }
@@ -631,7 +631,7 @@ class Pico
 
                 $this->plugins[$className] = $plugin;
 
-                if (defined($className . '::API_VERSION') && ($className::API_VERSION >= static::API_VERSION)) {
+                if (defined($className . '::API_VERSION') && ($className::API_VERSION >= self::API_VERSION)) {
                     $this->nativePlugins[$className] = $plugin;
                 }
             }
@@ -668,12 +668,9 @@ class Pico
     protected function loadLocalPlugins(array $pluginBlacklist = []): void
     {
         // scope isolated require()
-        $includeClosure = function ($pluginFile) {
+        $includeClosure = static function ($pluginFile) {
             require($pluginFile);
         };
-        if (PHP_VERSION_ID >= 50400) {
-            $includeClosure = $includeClosure->bindTo(null);
-        }
 
         $pluginBlacklist = array_fill_keys($pluginBlacklist, true);
 
@@ -714,7 +711,7 @@ class Pico
                 $this->plugins[$className] = $plugin;
 
                 if ($plugin instanceof PicoPluginInterface) {
-                    if (defined($className . '::API_VERSION') && ($className::API_VERSION >= static::API_VERSION)) {
+                    if (defined($className . '::API_VERSION') && ($className::API_VERSION >= self::API_VERSION)) {
                         $this->nativePlugins[$className] = $plugin;
                     }
                 }
@@ -780,7 +777,7 @@ class Pico
 
         $this->plugins[$className] = $plugin;
 
-        if (defined($className . '::API_VERSION') && ($className::API_VERSION >= static::API_VERSION)) {
+        if (defined($className . '::API_VERSION') && ($className::API_VERSION >= self::API_VERSION)) {
             $this->nativePlugins[$className] = $plugin;
         }
 
@@ -1172,10 +1169,10 @@ class Pico
         }
 
         // check for theme compatibility
-        if (!isset($this->plugins['PicoDeprecated']) && ($this->themeApiVersion < static::API_VERSION)) {
+        if (!isset($this->plugins['PicoDeprecated']) && ($this->themeApiVersion < self::API_VERSION)) {
             throw new RuntimeException(
                 'Current theme "' . $this->theme . '" uses API version ' . $this->themeApiVersion . ', but Pico '
-                . 'provides API version ' . static::API_VERSION . ' and PicoDeprecated isn\'t loaded'
+                . 'provides API version ' . self::API_VERSION . ' and PicoDeprecated isn\'t loaded'
             );
         }
     }
@@ -1651,7 +1648,7 @@ class Pico
         $variables = [];
 
         // replace %version%
-        $variables['%version%'] = static::VERSION;
+        $variables['%version%'] = self::VERSION;
 
         // replace %site_title%
         $variables['%site_title%'] = $this->getConfig('site_title');
@@ -2209,7 +2206,7 @@ class Pico
             'previous_page' => $this->previousPage,
             'current_page' => $this->currentPage,
             'next_page' => $this->nextPage,
-            'version' => static::VERSION,
+            'version' => self::VERSION,
         ];
     }