diff --git a/auth.php b/auth.php
index 69943d4..2af18a2 100644
--- a/auth.php
+++ b/auth.php
@@ -26,8 +26,8 @@
 
 use auth_userkey\core_userkey_manager;
 use auth_userkey\userkey_manager_interface;
+use core_external\external_value;
 
-require_once($CFG->libdir . "/externallib.php");
 require_once($CFG->libdir.'/authlib.php');
 require_once($CFG->dirroot . '/user/lib.php');
 
diff --git a/externallib.php b/externallib.php
index a25bb94..63ae24a 100644
--- a/externallib.php
+++ b/externallib.php
@@ -24,7 +24,11 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-require_once($CFG->libdir . "/externallib.php");
+use core_external\external_value;
+use core_external\external_api;
+use core_external\external_function_parameters;
+use core_external\external_single_structure;
+
 require_once($CFG->dirroot . "/webservice/lib.php");
 require_once($CFG->dirroot . "/auth/userkey/auth.php");
 
diff --git a/tests/auth_plugin_test.php b/tests/auth_plugin_test.php
index d295794..0e15d60 100644
--- a/tests/auth_plugin_test.php
+++ b/tests/auth_plugin_test.php
@@ -21,7 +21,7 @@
 use stdClass;
 use invalid_parameter_exception;
 use moodle_exception;
-use external_value;
+use core_external\external_value;
 
 /**
  * Tests for auth_plugin_userkey class.
@@ -57,7 +57,6 @@ class auth_plugin_test extends advanced_testcase {
     public function setUp(): void {
         global $CFG;
 
-        require_once($CFG->libdir . "/externallib.php");
         require_once($CFG->dirroot . '/auth/userkey/tests/fake_userkey_manager.php');
         require_once($CFG->dirroot . '/auth/userkey/auth.php');
         require_once($CFG->dirroot . '/user/lib.php');
diff --git a/tests/externallib_test.php b/tests/externallib_test.php
index ce42203..7011c12 100644
--- a/tests/externallib_test.php
+++ b/tests/externallib_test.php
@@ -19,7 +19,7 @@
 use advanced_testcase;
 use webservice_access_exception;
 use auth_userkey_external;
-use external_api;
+use core_external\external_api;
 use invalid_parameter_exception;
 use required_capability_exception;
 use context_system;
@@ -37,9 +37,9 @@ class externallib_test extends advanced_testcase {
     /**
      * User object.
      *
-     * @var
+     * @var stdClass
      */
-    protected $user = array();
+    protected $user;
 
     /**
      * Initial set up.
@@ -47,7 +47,6 @@ class externallib_test extends advanced_testcase {
     public function setUp(): void {
         global $CFG;
 
-        require_once($CFG->libdir . "/externallib.php");
         require_once($CFG->dirroot . '/auth/userkey/externallib.php');
 
         $this->resetAfterTest();