diff --git a/activitypub.php b/activitypub.php
index 3f582ea5..a1cd6df2 100644
--- a/activitypub.php
+++ b/activitypub.php
@@ -50,7 +50,7 @@ function init() {
 	Health_Check::init();
 	Scheduler::init();
 }
-\add_action( 'plugins_loaded', '\Activitypub\init' );
+\add_action( 'plugins_loaded', __NAMESPACE__ . '\init' );
 
 /**
  * Class Autoloader
@@ -143,7 +143,7 @@ function enable_buddypress_features() {
 	require_once \dirname( __FILE__ ) . '/integration/class-buddypress.php';
 	Integration\Buddypress::init();
 }
-add_action( 'bp_include', '\Activitypub\enable_buddypress_features' );
+add_action( 'bp_include', __NAMESPACE__ . '\enable_buddypress_features' );
 
 /**
  * `get_plugin_data` wrapper
diff --git a/integration/class-buddypress.php b/integration/class-buddypress.php
index 1087f47b..e4ec40e7 100644
--- a/integration/class-buddypress.php
+++ b/integration/class-buddypress.php
@@ -3,7 +3,7 @@ namespace Activitypub\Integration;
 
 class Buddypress {
 	public static function init() {
-		\add_filter( 'activitypub_json_author_array', array( 'Activitypub\Integration\Buddypress', 'add_user_metadata' ), 11, 2 );
+		\add_filter( 'activitypub_json_author_array', array( self::class, 'add_user_metadata' ), 11, 2 );
 	}
 
 	public static function add_user_metadata( $object, $author_id ) {