diff --git a/bij1rules.civix.php b/bij1rules.civix.php
index 97e3ed5..632ac86 100644
--- a/bij1rules.civix.php
+++ b/bij1rules.civix.php
@@ -24,7 +24,7 @@ class CRM_Bij1rules_ExtensionUtil {
    *   Translated text.
    * @see ts
    */
-  public static function ts($text, $params = []) {
+  public static function ts($text, $params = []): string {
     if (!array_key_exists('domain', $params)) {
       $params['domain'] = [self::LONG_NAME, NULL];
     }
@@ -41,7 +41,7 @@ class CRM_Bij1rules_ExtensionUtil {
    *   Ex: 'http://example.org/sites/default/ext/org.example.foo'.
    *   Ex: 'http://example.org/sites/default/ext/org.example.foo/css/foo.css'.
    */
-  public static function url($file = NULL) {
+  public static function url($file = NULL): string {
     if ($file === NULL) {
       return rtrim(CRM_Core_Resources::singleton()->getUrl(self::LONG_NAME), '/');
     }
@@ -79,6 +79,13 @@ class CRM_Bij1rules_ExtensionUtil {
 
 use CRM_Bij1rules_ExtensionUtil as E;
 
+function _bij1rules_civix_mixin_polyfill() {
+  if (!class_exists('CRM_Extension_MixInfo')) {
+    $polyfill = __DIR__ . '/mixin/polyfill.php';
+    (require $polyfill)(E::LONG_NAME, E::SHORT_NAME, E::path());
+  }
+}
+
 /**
  * (Delegated) Implements hook_civicrm_config().
  *
@@ -91,9 +98,9 @@ function _bij1rules_civix_civicrm_config(&$config = NULL) {
   }
   $configured = TRUE;
 
-  $template =& CRM_Core_Smarty::singleton();
+  $template = CRM_Core_Smarty::singleton();
 
-  $extRoot = dirname(__FILE__) . DIRECTORY_SEPARATOR;
+  $extRoot = __DIR__ . DIRECTORY_SEPARATOR;
   $extDir = $extRoot . 'templates';
 
   if (is_array($template->template_dir)) {
@@ -105,19 +112,7 @@ function _bij1rules_civix_civicrm_config(&$config = NULL) {
 
   $include_path = $extRoot . PATH_SEPARATOR . get_include_path();
   set_include_path($include_path);
-}
-
-/**
- * (Delegated) Implements hook_civicrm_xmlMenu().
- *
- * @param $files array(string)
- *
- * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_xmlMenu
- */
-function _bij1rules_civix_civicrm_xmlMenu(&$files) {
-  foreach (_bij1rules_civix_glob(__DIR__ . '/xml/Menu/*.xml') as $file) {
-    $files[] = $file;
-  }
+  _bij1rules_civix_mixin_polyfill();
 }
 
 /**
@@ -130,6 +125,7 @@ function _bij1rules_civix_civicrm_install() {
   if ($upgrader = _bij1rules_civix_upgrader()) {
     $upgrader->onInstall();
   }
+  _bij1rules_civix_mixin_polyfill();
 }
 
 /**
@@ -151,7 +147,7 @@ function _bij1rules_civix_civicrm_postInstall() {
  *
  * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_uninstall
  */
-function _bij1rules_civix_civicrm_uninstall() {
+function _bij1rules_civix_civicrm_uninstall(): void {
   _bij1rules_civix_civicrm_config();
   if ($upgrader = _bij1rules_civix_upgrader()) {
     $upgrader->onUninstall();
@@ -163,13 +159,14 @@ function _bij1rules_civix_civicrm_uninstall() {
  *
  * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_enable
  */
-function _bij1rules_civix_civicrm_enable() {
+function _bij1rules_civix_civicrm_enable(): void {
   _bij1rules_civix_civicrm_config();
   if ($upgrader = _bij1rules_civix_upgrader()) {
     if (is_callable([$upgrader, 'onEnable'])) {
       $upgrader->onEnable();
     }
   }
+  _bij1rules_civix_mixin_polyfill();
 }
 
 /**
@@ -178,7 +175,7 @@ function _bij1rules_civix_civicrm_enable() {
  * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_disable
  * @return mixed
  */
-function _bij1rules_civix_civicrm_disable() {
+function _bij1rules_civix_civicrm_disable(): void {
   _bij1rules_civix_civicrm_config();
   if ($upgrader = _bij1rules_civix_upgrader()) {
     if (is_callable([$upgrader, 'onDisable'])) {
@@ -217,136 +214,6 @@ function _bij1rules_civix_upgrader() {
   }
 }
 
-/**
- * Search directory tree for files which match a glob pattern.
- *
- * Note: Dot-directories (like "..", ".git", or ".svn") will be ignored.
- * Note: Delegate to CRM_Utils_File::findFiles(), this function kept only
- * for backward compatibility of extension code that uses it.
- *
- * @param string $dir base dir
- * @param string $pattern , glob pattern, eg "*.txt"
- *
- * @return array
- */
-function _bij1rules_civix_find_files($dir, $pattern) {
-  return CRM_Utils_File::findFiles($dir, $pattern);
-}
-
-/**
- * (Delegated) Implements hook_civicrm_managed().
- *
- * Find any *.mgd.php files, merge their content, and return.
- *
- * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_managed
- */
-function _bij1rules_civix_civicrm_managed(&$entities) {
-  $mgdFiles = _bij1rules_civix_find_files(__DIR__, '*.mgd.php');
-  sort($mgdFiles);
-  foreach ($mgdFiles as $file) {
-    $es = include $file;
-    foreach ($es as $e) {
-      if (empty($e['module'])) {
-        $e['module'] = E::LONG_NAME;
-      }
-      if (empty($e['params']['version'])) {
-        $e['params']['version'] = '3';
-      }
-      $entities[] = $e;
-    }
-  }
-}
-
-/**
- * (Delegated) Implements hook_civicrm_caseTypes().
- *
- * Find any and return any files matching "xml/case/*.xml"
- *
- * Note: This hook only runs in CiviCRM 4.4+.
- *
- * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_caseTypes
- */
-function _bij1rules_civix_civicrm_caseTypes(&$caseTypes) {
-  if (!is_dir(__DIR__ . '/xml/case')) {
-    return;
-  }
-
-  foreach (_bij1rules_civix_glob(__DIR__ . '/xml/case/*.xml') as $file) {
-    $name = preg_replace('/\.xml$/', '', basename($file));
-    if ($name != CRM_Case_XMLProcessor::mungeCaseType($name)) {
-      $errorMessage = sprintf("Case-type file name is malformed (%s vs %s)", $name, CRM_Case_XMLProcessor::mungeCaseType($name));
-      throw new CRM_Core_Exception($errorMessage);
-    }
-    $caseTypes[$name] = [
-      'module' => E::LONG_NAME,
-      'name' => $name,
-      'file' => $file,
-    ];
-  }
-}
-
-/**
- * (Delegated) Implements hook_civicrm_angularModules().
- *
- * Find any and return any files matching "ang/*.ang.php"
- *
- * Note: This hook only runs in CiviCRM 4.5+.
- *
- * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_angularModules
- */
-function _bij1rules_civix_civicrm_angularModules(&$angularModules) {
-  if (!is_dir(__DIR__ . '/ang')) {
-    return;
-  }
-
-  $files = _bij1rules_civix_glob(__DIR__ . '/ang/*.ang.php');
-  foreach ($files as $file) {
-    $name = preg_replace(':\.ang\.php$:', '', basename($file));
-    $module = include $file;
-    if (empty($module['ext'])) {
-      $module['ext'] = E::LONG_NAME;
-    }
-    $angularModules[$name] = $module;
-  }
-}
-
-/**
- * (Delegated) Implements hook_civicrm_themes().
- *
- * Find any and return any files matching "*.theme.php"
- */
-function _bij1rules_civix_civicrm_themes(&$themes) {
-  $files = _bij1rules_civix_glob(__DIR__ . '/*.theme.php');
-  foreach ($files as $file) {
-    $themeMeta = include $file;
-    if (empty($themeMeta['name'])) {
-      $themeMeta['name'] = preg_replace(':\.theme\.php$:', '', basename($file));
-    }
-    if (empty($themeMeta['ext'])) {
-      $themeMeta['ext'] = E::LONG_NAME;
-    }
-    $themes[$themeMeta['name']] = $themeMeta;
-  }
-}
-
-/**
- * Glob wrapper which is guaranteed to return an array.
- *
- * The documentation for glob() says, "On some systems it is impossible to
- * distinguish between empty match and an error." Anecdotally, the return
- * result for an empty match is sometimes array() and sometimes FALSE.
- * This wrapper provides consistency.
- *
- * @link http://php.net/glob
- * @param string $pattern
- *
- * @return array
- */
-function _bij1rules_civix_glob($pattern) {
-  $result = glob($pattern);
-  return is_array($result) ? $result : [];
-}
-
 /**
  * Inserts a navigation menu item at a given place in the hierarchy.
  *
@@ -429,18 +296,6 @@ function _bij1rules_civix_fixNavigationMenuItems(&$nodes, &$maxNavID, $parentID)
   }
 }
 
-/**
- * (Delegated) Implements hook_civicrm_alterSettingsFolders().
- *
- * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_alterSettingsFolders
- */
-function _bij1rules_civix_civicrm_alterSettingsFolders(&$metaDataFolders = NULL) {
-  $settingsDir = __DIR__ . DIRECTORY_SEPARATOR . 'settings';
-  if (!in_array($settingsDir, $metaDataFolders) && is_dir($settingsDir)) {
-    $metaDataFolders[] = $settingsDir;
-  }
-}
-
 /**
  * (Delegated) Implements hook_civicrm_entityTypes().
  *
diff --git a/bij1rules.php b/bij1rules.php
index 6124326..c0bb934 100644
--- a/bij1rules.php
+++ b/bij1rules.php
@@ -14,15 +14,6 @@ function bij1rules_civicrm_config(&$config) {
   _bij1rules_civix_civicrm_config($config);
 }
 
-/**
- * Implements hook_civicrm_xmlMenu().
- *
- * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_xmlMenu
- */
-function bij1rules_civicrm_xmlMenu(&$files) {
-  _bij1rules_civix_civicrm_xmlMenu($files);
-}
-
 /**
  * Implements hook_civicrm_install().
  *
@@ -77,54 +68,6 @@ function bij1rules_civicrm_upgrade($op, CRM_Queue_Queue $queue = NULL) {
   return _bij1rules_civix_civicrm_upgrade($op, $queue);
 }
 
-/**
- * Implements hook_civicrm_managed().
- *
- * Generate a list of entities to create/deactivate/delete when this module
- * is installed, disabled, uninstalled.
- *
- * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_managed
- */
-function bij1rules_civicrm_managed(&$entities) {
-  _bij1rules_civix_civicrm_managed($entities);
-}
-
-/**
- * Implements hook_civicrm_caseTypes().
- *
- * Generate a list of case-types.
- *
- * Note: This hook only runs in CiviCRM 4.4+.
- *
- * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_caseTypes
- */
-function bij1rules_civicrm_caseTypes(&$caseTypes) {
-  _bij1rules_civix_civicrm_caseTypes($caseTypes);
-}
-
-/**
- * Implements hook_civicrm_angularModules().
- *
- * Generate a list of Angular modules.
- *
- * Note: This hook only runs in CiviCRM 4.5+. It may
- * use features only available in v4.6+.
- *
- * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_angularModules
- */
-function bij1rules_civicrm_angularModules(&$angularModules) {
-  _bij1rules_civix_civicrm_angularModules($angularModules);
-}
-
-/**
- * Implements hook_civicrm_alterSettingsFolders().
- *
- * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_alterSettingsFolders
- */
-function bij1rules_civicrm_alterSettingsFolders(&$metaDataFolders = NULL) {
-  _bij1rules_civix_civicrm_alterSettingsFolders($metaDataFolders);
-}
-
 /**
  * Implements hook_civicrm_entityTypes().
  *
@@ -136,13 +79,6 @@ function bij1rules_civicrm_entityTypes(&$entityTypes) {
   _bij1rules_civix_civicrm_entityTypes($entityTypes);
 }
 
-/**
- * Implements hook_civicrm_themes().
- */
-function bij1rules_civicrm_themes(&$themes) {
-  _bij1rules_civix_civicrm_themes($themes);
-}
-
 // --- Functions below this ship commented out. Uncomment as required. ---
 
 /**
diff --git a/info.xml b/info.xml
index 2a89e1f..23ad430 100644
--- a/info.xml
+++ b/info.xml
@@ -29,5 +29,6 @@
   </classloader>
   <civix>
     <namespace>CRM/Bij1rules</namespace>
+    <format>22.10.0</format>
   </civix>
 </extension>
diff --git a/mixin/polyfill.php b/mixin/polyfill.php
new file mode 100644
index 0000000..ef111e6
--- /dev/null
+++ b/mixin/polyfill.php
@@ -0,0 +1,554 @@
+<?php
+
+// AUTO-GENERATED FILE -- Civix may overwrite any changes made to this file
+
+/**
+ * The ExtensionUtil class provides small stubs for accessing resources of this
+ * extension.
+ */
+class CRM_Bij1rules_ExtensionUtil {
+  const SHORT_NAME = 'bij1rules';
+  const LONG_NAME = 'bij1rules';
+  const CLASS_PREFIX = 'CRM_Bij1rules';
+
+  /**
+   * Translate a string using the extension's domain.
+   *
+   * If the extension doesn't have a specific translation
+   * for the string, fallback to the default translations.
+   *
+   * @param string $text
+   *   Canonical message text (generally en_US).
+   * @param array $params
+   * @return string
+   *   Translated text.
+   * @see ts
+   */
+  public static function ts($text, $params = []) {
+    if (!array_key_exists('domain', $params)) {
+      $params['domain'] = [self::LONG_NAME, NULL];
+    }
+    return ts($text, $params);
+  }
+
+  /**
+   * Get the URL of a resource file (in this extension).
+   *
+   * @param string|NULL $file
+   *   Ex: NULL.
+   *   Ex: 'css/foo.css'.
+   * @return string
+   *   Ex: 'http://example.org/sites/default/ext/org.example.foo'.
+   *   Ex: 'http://example.org/sites/default/ext/org.example.foo/css/foo.css'.
+   */
+  public static function url($file = NULL) {
+    if ($file === NULL) {
+      return rtrim(CRM_Core_Resources::singleton()->getUrl(self::LONG_NAME), '/');
+    }
+    return CRM_Core_Resources::singleton()->getUrl(self::LONG_NAME, $file);
+  }
+
+  /**
+   * Get the path of a resource file (in this extension).
+   *
+   * @param string|NULL $file
+   *   Ex: NULL.
+   *   Ex: 'css/foo.css'.
+   * @return string
+   *   Ex: '/var/www/example.org/sites/default/ext/org.example.foo'.
+   *   Ex: '/var/www/example.org/sites/default/ext/org.example.foo/css/foo.css'.
+   */
+  public static function path($file = NULL) {
+    // return CRM_Core_Resources::singleton()->getPath(self::LONG_NAME, $file);
+    return __DIR__ . ($file === NULL ? '' : (DIRECTORY_SEPARATOR . $file));
+  }
+
+  /**
+   * Get the name of a class within this extension.
+   *
+   * @param string $suffix
+   *   Ex: 'Page_HelloWorld' or 'Page\\HelloWorld'.
+   * @return string
+   *   Ex: 'CRM_Foo_Page_HelloWorld'.
+   */
+  public static function findClass($suffix) {
+    return self::CLASS_PREFIX . '_' . str_replace('\\', '_', $suffix);
+  }
+
+}
+
+use CRM_Bij1rules_ExtensionUtil as E;
+
+/**
+ * (Delegated) Implements hook_civicrm_config().
+ *
+ * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_config
+ */
+function _bij1rules_civix_civicrm_config(&$config = NULL) {
+  static $configured = FALSE;
+  if ($configured) {
+    return;
+  }
+  $configured = TRUE;
+
+  $template =& CRM_Core_Smarty::singleton();
+
+  $extRoot = dirname(__FILE__) . DIRECTORY_SEPARATOR;
+  $extDir = $extRoot . 'templates';
+
+  if (is_array($template->template_dir)) {
+    array_unshift($template->template_dir, $extDir);
+  }
+  else {
+    $template->template_dir = [$extDir, $template->template_dir];
+  }
+
+  $include_path = $extRoot . PATH_SEPARATOR . get_include_path();
+  set_include_path($include_path);
+}
+
+/**
+ * (Delegated) Implements hook_civicrm_xmlMenu().
+ *
+ * @param $files array(string)
+ *
+ * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_xmlMenu
+ */
+function _bij1rules_civix_civicrm_xmlMenu(&$files) {
+  foreach (_bij1rules_civix_glob(__DIR__ . '/xml/Menu/*.xml') as $file) {
+    $files[] = $file;
+  }
+}
+
+/**
+ * Implements hook_civicrm_install().
+ *
+ * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_install
+ */
+function _bij1rules_civix_civicrm_install() {
+  _bij1rules_civix_civicrm_config();
+  if ($upgrader = _bij1rules_civix_upgrader()) {
+    $upgrader->onInstall();
+  }
+}
+
+/**
+ * Implements hook_civicrm_postInstall().
+ *
+ * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_postInstall
+ */
+function _bij1rules_civix_civicrm_postInstall() {
+  _bij1rules_civix_civicrm_config();
+  if ($upgrader = _bij1rules_civix_upgrader()) {
+    if (is_callable([$upgrader, 'onPostInstall'])) {
+      $upgrader->onPostInstall();
+    }
+  }
+}
+
+/**
+ * Implements hook_civicrm_uninstall().
+ *
+ * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_uninstall
+ */
+function _bij1rules_civix_civicrm_uninstall() {
+  _bij1rules_civix_civicrm_config();
+  if ($upgrader = _bij1rules_civix_upgrader()) {
+    $upgrader->onUninstall();
+  }
+}
+
+/**
+ * (Delegated) Implements hook_civicrm_enable().
+ *
+ * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_enable
+ */
+function _bij1rules_civix_civicrm_enable() {
+  _bij1rules_civix_civicrm_config();
+  if ($upgrader = _bij1rules_civix_upgrader()) {
+    if (is_callable([$upgrader, 'onEnable'])) {
+      $upgrader->onEnable();
+    }
+  }
+}
+
+/**
+ * (Delegated) Implements hook_civicrm_disable().
+ *
+ * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_disable
+ * @return mixed
+ */
+function _bij1rules_civix_civicrm_disable() {
+  _bij1rules_civix_civicrm_config();
+  if ($upgrader = _bij1rules_civix_upgrader()) {
+    if (is_callable([$upgrader, 'onDisable'])) {
+      $upgrader->onDisable();
+    }
+  }
+}
+
+/**
+ * (Delegated) Implements hook_civicrm_upgrade().
+ *
+ * @param $op string, the type of operation being performed; 'check' or 'enqueue'
+ * @param $queue CRM_Queue_Queue, (for 'enqueue') the modifiable list of pending up upgrade tasks
+ *
+ * @return mixed
+ *   based on op. for 'check', returns array(boolean) (TRUE if upgrades are pending)
+ *   for 'enqueue', returns void
+ *
+ * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_upgrade
+ */
+function _bij1rules_civix_civicrm_upgrade($op, CRM_Queue_Queue $queue = NULL) {
+  if ($upgrader = _bij1rules_civix_upgrader()) {
+    return $upgrader->onUpgrade($op, $queue);
+  }
+}
+
+/**
+ * @return CRM_Bij1rules_Upgrader
+ */
+function _bij1rules_civix_upgrader() {
+  if (!file_exists(__DIR__ . '/CRM/Bij1rules/Upgrader.php')) {
+    return NULL;
+  }
+  else {
+    return CRM_Bij1rules_Upgrader_Base::instance();
+  }
+}
+
+/**
+ * Search directory tree for files which match a glob pattern.
+ *
+ * Note: Dot-directories (like "..", ".git", or ".svn") will be ignored.
+ * Note: Delegate to CRM_Utils_File::findFiles(), this function kept only
+ * for backward compatibility of extension code that uses it.
+ *
+ * @param string $dir base dir
+ * @param string $pattern , glob pattern, eg "*.txt"
+ *
+ * @return array
+ */
+function _bij1rules_civix_find_files($dir, $pattern) {
+  return CRM_Utils_File::findFiles($dir, $pattern);
+}
+
+/**
+ * (Delegated) Implements hook_civicrm_managed().
+ *
+ * Find any *.mgd.php files, merge their content, and return.
+ *
+ * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_managed
+ */
+function _bij1rules_civix_civicrm_managed(&$entities) {
+  $mgdFiles = _bij1rules_civix_find_files(__DIR__, '*.mgd.php');
+  sort($mgdFiles);
+  foreach ($mgdFiles as $file) {
+    $es = include $file;
+    foreach ($es as $e) {
+      if (empty($e['module'])) {
+        $e['module'] = E::LONG_NAME;
+      }
+      if (empty($e['params']['version'])) {
+        $e['params']['version'] = '3';
+      }
+      $entities[] = $e;
+    }
+  }
+}
+
+/**
+ * (Delegated) Implements hook_civicrm_caseTypes().
+ *
+ * Find any and return any files matching "xml/case/*.xml"
+ *
+ * Note: This hook only runs in CiviCRM 4.4+.
+ *
+ * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_caseTypes
+ */
+function _bij1rules_civix_civicrm_caseTypes(&$caseTypes) {
+  if (!is_dir(__DIR__ . '/xml/case')) {
+    return;
+  }
+
+  foreach (_bij1rules_civix_glob(__DIR__ . '/xml/case/*.xml') as $file) {
+    $name = preg_replace('/\.xml$/', '', basename($file));
+    if ($name != CRM_Case_XMLProcessor::mungeCaseType($name)) {
+      $errorMessage = sprintf("Case-type file name is malformed (%s vs %s)", $name, CRM_Case_XMLProcessor::mungeCaseType($name));
+      throw new CRM_Core_Exception($errorMessage);
+    }
+    $caseTypes[$name] = [
+      'module' => E::LONG_NAME,
+      'name' => $name,
+      'file' => $file,
+    ];
+  }
+}
+
+/**
+ * (Delegated) Implements hook_civicrm_angularModules().
+ *
+ * Find any and return any files matching "ang/*.ang.php"
+ *
+ * Note: This hook only runs in CiviCRM 4.5+.
+ *
+ * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_angularModules
+ */
+function _bij1rules_civix_civicrm_angularModules(&$angularModules) {
+  if (!is_dir(__DIR__ . '/ang')) {
+    return;
+  }
+
+  $files = _bij1rules_civix_glob(__DIR__ . '/ang/*.ang.php');
+  foreach ($files as $file) {
+    $name = preg_replace(':\.ang\.php$:', '', basename($file));
+    $module = include $file;
+    if (empty($module['ext'])) {
+      $module['ext'] = E::LONG_NAME;
+    }
+    $angularModules[$name] = $module;
+  }
+}
+
+/**
+ * (Delegated) Implements hook_civicrm_themes().
+ *
+ * Find any and return any files matching "*.theme.php"
+ */
+function _bij1rules_civix_civicrm_themes(&$themes) {
+  $files = _bij1rules_civix_glob(__DIR__ . '/*.theme.php');
+  foreach ($files as $file) {
+    $themeMeta = include $file;
+    if (empty($themeMeta['name'])) {
+      $themeMeta['name'] = preg_replace(':\.theme\.php$:', '', basename($file));
+    }
+    if (empty($themeMeta['ext'])) {
+      $themeMeta['ext'] = E::LONG_NAME;
+    }
+    $themes[$themeMeta['name']] = $themeMeta;
+  }
+}
+
+/**
+ * Glob wrapper which is guaranteed to return an array.
+ *
+ * The documentation for glob() says, "On some systems it is impossible to
+ * distinguish between empty match and an error." Anecdotally, the return
+ * result for an empty match is sometimes array() and sometimes FALSE.
+ * This wrapper provides consistency.
+ *
+ * @link http://php.net/glob
+ * @param string $pattern
+ *
+ * @return array
+ */
+function _bij1rules_civix_glob($pattern) {
+  $result = glob($pattern);
+  return is_array($result) ? $result : [];
+}
+
+/**
+ * Inserts a navigation menu item at a given place in the hierarchy.
+ *
+ * @param array $menu - menu hierarchy
+ * @param string $path - path to parent of this item, e.g. 'my_extension/submenu'
+ *    'Mailing', or 'Administer/System Settings'
+ * @param array $item - the item to insert (parent/child attributes will be
+ *    filled for you)
+ *
+ * @return bool
+ */
+function _bij1rules_civix_insert_navigation_menu(&$menu, $path, $item) {
+  // If we are done going down the path, insert menu
+  if (empty($path)) {
+    $menu[] = [
+      'attributes' => array_merge([
+        'label'      => CRM_Utils_Array::value('name', $item),
+        'active'     => 1,
+      ], $item),
+    ];
+    return TRUE;
+  }
+  else {
+    // Find an recurse into the next level down
+    $found = FALSE;
+    $path = explode('/', $path);
+    $first = array_shift($path);
+    foreach ($menu as $key => &$entry) {
+      if ($entry['attributes']['name'] == $first) {
+        if (!isset($entry['child'])) {
+          $entry['child'] = [];
+        }
+        $found = _bij1rules_civix_insert_navigation_menu($entry['child'], implode('/', $path), $item);
+      }
+    }
+    return $found;
+  }
+}
+
+/**
+ * (Delegated) Implements hook_civicrm_navigationMenu().
+ */
+function _bij1rules_civix_navigationMenu(&$nodes) {
+  if (!is_callable(['CRM_Core_BAO_Navigation', 'fixNavigationMenu'])) {
+    _bij1rules_civix_fixNavigationMenu($nodes);
+  }
+}
+
+/**
+ * Given a navigation menu, generate navIDs for any items which are
+ * missing them.
+ */
+function _bij1rules_civix_fixNavigationMenu(&$nodes) {
+  $maxNavID = 1;
+  array_walk_recursive($nodes, function($item, $key) use (&$maxNavID) {
+    if ($key === 'navID') {
+      $maxNavID = max($maxNavID, $item);
+    }
+  });
+  _bij1rules_civix_fixNavigationMenuItems($nodes, $maxNavID, NULL);
+}
+
+function _bij1rules_civix_fixNavigationMenuItems(&$nodes, &$maxNavID, $parentID) {
+  $origKeys = array_keys($nodes);
+  foreach ($origKeys as $origKey) {
+    if (!isset($nodes[$origKey]['attributes']['parentID']) && $parentID !== NULL) {
+      $nodes[$origKey]['attributes']['parentID'] = $parentID;
+    }
+    // If no navID, then assign navID and fix key.
+    if (!isset($nodes[$origKey]['attributes']['navID'])) {
+      $newKey = ++$maxNavID;
+      $nodes[$origKey]['attributes']['navID'] = $newKey;
+      $nodes[$newKey] = $nodes[$origKey];
+      unset($nodes[$origKey]);
+      $origKey = $newKey;
+    }
+    if (isset($nodes[$origKey]['child']) && is_array($nodes[$origKey]['child'])) {
+      _bij1rules_civix_fixNavigationMenuItems($nodes[$origKey]['child'], $maxNavID, $nodes[$origKey]['attributes']['navID']);
+    }
+  }
+}
+
+/**
+ * (Delegated) Implements hook_civicrm_alterSettingsFolders().
+ *
+ * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_alterSettingsFolders
+ */
+function _bij1rules_civix_civicrm_alterSettingsFolders(&$metaDataFolders = NULL) {
+  $settingsDir = __DIR__ . DIRECTORY_SEPARATOR . 'settings';
+  if (!in_array($settingsDir, $metaDataFolders) && is_dir($settingsDir)) {
+    $metaDataFolders[] = $settingsDir;
+  }
+}
+
+/**
+ * (Delegated) Implements hook_civicrm_entityTypes().
+ *
+ * Find any *.entityType.php files, merge their content, and return.
+ *
+ * @link https://docs.civicrm.org/dev/en/latest/hooks/hook_civicrm_entityTypes
+ */
+function _bij1rules_civix_civicrm_entityTypes(&$entityTypes) {
+  $entityTypes = array_merge($entityTypes, []);
+}
+<?php
+
+/**
+ * When deploying on systems that lack mixin support, fake it.
+ *
+ * @mixinFile polyfill.php
+ *
+ * This polyfill does some (persnickity) deduplication, but it doesn't allow upgrades or shipping replacements in core.
+ *
+ * Note: The polyfill.php is designed to be copied into extensions for interoperability. Consequently, this file is
+ * not used 'live' by `civicrm-core`. However, the file does need a canonical home, and it's convenient to keep it
+ * adjacent to the actual mixin files.
+ *
+ * @param string $longName
+ * @param string $shortName
+ * @param string $basePath
+ */
+return function ($longName, $shortName, $basePath) {
+  // Construct imitations of the mixin services. These cannot work as well (e.g. with respect to
+  // number of file-reads, deduping, upgrading)... but they should be OK for a few months while
+  // the mixin services become available.
+
+  // List of active mixins; deduped by version
+  $mixinVers = [];
+  foreach ((array) glob($basePath . '/mixin/*.mixin.php') as $f) {
+    [$name, $ver] = explode('@', substr(basename($f), 0, -10));
+    if (!isset($mixinVers[$name]) || version_compare($ver, $mixinVers[$name], '>')) {
+      $mixinVers[$name] = $ver;
+    }
+  }
+  $mixins = [];
+  foreach ($mixinVers as $name => $ver) {
+    $mixins[] = "$name@$ver";
+  }
+
+  // Imitate CRM_Extension_MixInfo.
+  $mixInfo = new class() {
+
+    /**
+     * @var string
+     */
+    public $longName;
+
+    /**
+     * @var string
+     */
+    public $shortName;
+
+    public $_basePath;
+
+    public function getPath($file = NULL) {
+      return $this->_basePath . ($file === NULL ? '' : (DIRECTORY_SEPARATOR . $file));
+    }
+
+    public function isActive() {
+      return \CRM_Extension_System::singleton()->getMapper()->isActiveModule($this->shortName);
+    }
+
+  };
+  $mixInfo->longName = $longName;
+  $mixInfo->shortName = $shortName;
+  $mixInfo->_basePath = $basePath;
+
+  // Imitate CRM_Extension_BootCache.
+  $bootCache = new class() {
+
+    public function define($name, $callback) {
+      $envId = \CRM_Core_Config_Runtime::getId();
+      $oldExtCachePath = \Civi::paths()->getPath("[civicrm.compile]/CachedExtLoader.{$envId}.php");
+      $stat = stat($oldExtCachePath);
+      $file = Civi::paths()->getPath('[civicrm.compile]/CachedMixin.' . md5($name . ($stat['mtime'] ?? 0)) . '.php');
+      if (file_exists($file)) {
+        return include $file;
+      }
+      else {
+        $data = $callback();
+        file_put_contents($file, '<' . "?php\nreturn " . var_export($data, 1) . ';');
+        return $data;
+      }
+    }
+
+  };
+
+  // Imitate CRM_Extension_MixinLoader::run()
+  // Parse all live mixins before trying to scan any classes.
+  global $_CIVIX_MIXIN_POLYFILL;
+  foreach ($mixins as $mixin) {
+    // If the exact same mixin is defined by multiple exts, just use the first one.
+    if (!isset($_CIVIX_MIXIN_POLYFILL[$mixin])) {
+      $_CIVIX_MIXIN_POLYFILL[$mixin] = include_once $basePath . '/mixin/' . $mixin . '.mixin.php';
+    }
+  }
+  foreach ($mixins as $mixin) {
+    // If there's trickery about installs/uninstalls/resets, then we may need to register a second time.
+    if (!isset(\Civi::$statics[__FUNCTION__][$mixin])) {
+      \Civi::$statics[__FUNCTION__][$mixin] = 1;
+      $func = $_CIVIX_MIXIN_POLYFILL[$mixin];
+      $func($mixInfo, $bootCache);
+    }
+  }
+};