diff --git a/includes/class-user-factory.php b/includes/class-user-factory.php
index faa170e..8ba4521 100644
--- a/includes/class-user-factory.php
+++ b/includes/class-user-factory.php
@@ -58,7 +58,7 @@ class User_Factory {
 	 */
 	public static function get_by_username( $username ) {
 		// check for blog user.
-		if ( get_option( 'activitypub_blog_user_identifier', null ) === $username ) {
+		if ( Blog_User::get_default_username() === $username ) {
 			return self::get_by_id( self::BLOG_USER_ID );
 		}
 
diff --git a/includes/model/class-blog-user.php b/includes/model/class-blog-user.php
index fd01aa7..492bf76 100644
--- a/includes/model/class-blog-user.php
+++ b/includes/model/class-blog-user.php
@@ -59,8 +59,55 @@ class Blog_User extends User {
 		return \get_home_url();
 	}
 
+	/**
+	 * Generate and save a default Username.
+	 *
+	 * @return string The auto-generated Username.
+	 */
+	public static function get_default_username() {
+		$username = \get_option( 'activitypub_blog_user_identifier' );
+
+		if ( $username ) {
+			return $username;
+		}
+
+		// check if domain host has a subdomain
+		$host       = \wp_parse_url( \get_home_url(), \PHP_URL_HOST );
+		$host       = \str_replace( 'www.', '', $host );
+		$host_parts = \explode( '.', $host );
+
+		if ( \count( $host_parts ) <= 2 && strlen( $host ) <= 15 ) {
+			\update_option( 'activitypub_blog_user_identifier', $host );
+			return $host;
+		}
+
+		// check blog title
+		$blog_title = \get_bloginfo( 'name' );
+		$blog_title = \sanitize_title( $blog_title );
+
+		if ( strlen( $blog_title ) <= 15 ) {
+			\update_option( 'activitypub_blog_user_identifier', $blog_title );
+			return $blog_title;
+		}
+
+		$default_identifier = array(
+			'feed',
+			'all',
+			'everyone',
+			'authors',
+			'follow',
+			'posts',
+		);
+
+		// get random item of $default_identifier
+		$default = $default_identifier[ \array_rand( $default_identifier ) ];
+		\update_option( 'activitypub_blog_user_identifier', $default );
+
+		return $default;
+	}
+
 	public function get_username() {
-		return \esc_html( \get_option( 'activitypub_blog_user_identifier', 'feed' ) );
+		return self::get_default_username();
 	}
 
 	public function get_avatar() {
diff --git a/templates/blog-json.php b/templates/blog-json.php
index b87bc94..cfa759c 100644
--- a/templates/blog-json.php
+++ b/templates/blog-json.php
@@ -1,66 +1,10 @@
 <?php
-$json = new \stdClass();
-
-$json->{'@context'} = \Activitypub\get_context();
-$json->id = \get_home_url( '/' );
-$json->type = 'Organization';
-$json->name = \get_bloginfo( 'name' );
-$json->summary = \html_entity_decode(
-	\get_bloginfo( 'description' ),
-	\ENT_QUOTES,
-	'UTF-8'
-);
-$json->preferredUsername = \get_bloginfo( 'name' ); // phpcs:ignore
-$json->url = \get_home_url( '/' );
-
-if ( \has_site_icon() ) {
-	$json->icon = array(
-		'type' => 'Image',
-		'url'  => \get_site_icon_url( 120 ),
-	);
-}
-
-if ( \has_header_image() ) {
-	$json->image = array(
-		'type' => 'Image',
-		'url'  => \get_header_image(),
-	);
-}
-
-$json->inbox = \Activitypub\get_rest_url_by_path( 'blog/inbox' );
-$json->outbox = \Activitypub\get_rest_url_by_path( 'blog/outbox' );
-$json->followers = \Activitypub\get_rest_url_by_path( 'blog/followers' );
-$json->following = \Activitypub\get_rest_url_by_path( 'blog/following' );
-
-$json->manuallyApprovesFollowers = \apply_filters( 'activitypub_json_manually_approves_followers', \__return_false() ); // phpcs:ignore
-
-// phpcs:ignore
-$json->publicKey = array(
-	'id' => \get_home_url( '/' ) . '#main-key',
-	'owner' => \get_home_url( '/' ),
-	'publicKeyPem' => '',
-);
-
-$json->tag = array();
-$json->attachment = array();
-
-$json->attachment[] = array(
-	'type' => 'PropertyValue',
-	'name' => \__( 'Blog', 'activitypub' ),
-	'value' => \html_entity_decode(
-		'<a rel="me" title="' . \esc_attr( \home_url( '/' ) ) . '" target="_blank" href="' . \home_url( '/' ) . '">' . \wp_parse_url( \home_url( '/' ), \PHP_URL_HOST ) . '</a>',
-		\ENT_QUOTES,
-		'UTF-8'
-	),
-);
-
-// filter output
-$json = \apply_filters( 'activitypub_json_blog_array', $json );
+$user = \Activitypub\User_Factory::get_by_id( 0 );
 
 /*
  * Action triggerd prior to the ActivityPub profile being created and sent to the client
  */
-\do_action( 'activitypub_json_blog_pre' );
+\do_action( 'activitypub_json_author_pre', $user->get_user_id() );
 
 $options = 0;
 // JSON_PRETTY_PRINT added in PHP 5.4
@@ -75,12 +19,12 @@ $options |= \JSON_HEX_TAG | \JSON_HEX_AMP | \JSON_HEX_QUOT;
  *
  * @param int $options The current options flags
  */
-$options = \apply_filters( 'activitypub_json_blog_options', $options );
+$options = \apply_filters( 'activitypub_json_author_options', $options, $user->get_user_id() );
 
 \header( 'Content-Type: application/activity+json' );
-echo \wp_json_encode( $json, $options );
+echo \wp_json_encode( $user->to_array(), $options );
 
 /*
  * Action triggerd after the ActivityPub profile has been created and sent to the client
  */
-\do_action( 'activitypub_json_blog_post' );
+\do_action( 'activitypub_json_author_post', $user->get_user_id() );
diff --git a/templates/settings.php b/templates/settings.php
index 819dbb0..08a65a1 100644
--- a/templates/settings.php
+++ b/templates/settings.php
@@ -42,7 +42,7 @@
 					</th>
 					<td>
 						<label for="activitypub_blog_user_identifier">
-							<input class="blog-user-identifier" name="activitypub_blog_user_identifier" id="activitypub_blog_user_identifier" type="text" value="<?php echo esc_attr( \get_option( 'activitypub_blog_user_identifier', 'feed' ) ); ?>" />
+							<input class="blog-user-identifier" name="activitypub_blog_user_identifier" id="activitypub_blog_user_identifier" type="text" value="<?php echo esc_attr( \get_option( 'activitypub_blog_user_identifier', \Activitypub\Model\Blog_User::get_default_username() ) ); ?>" />
 							@<?php echo esc_html( \wp_parse_url( \home_url(), PHP_URL_HOST ) ); ?>
 						</label>
 						<p class="description">