diff --git a/activitypub.php b/activitypub.php
index 2e731f2..6efc3c2 100644
--- a/activitypub.php
+++ b/activitypub.php
@@ -25,6 +25,7 @@ function init() {
 	\defined( 'ACTIVITYPUB_HASHTAGS_REGEXP' ) || \define( 'ACTIVITYPUB_HASHTAGS_REGEXP', '(?:(?<=\s)|(?<=<p>)|(?<=<br>)|^)#([A-Za-z0-9_]+)(?:(?=\s|[[:punct:]]|$))' );
 	\defined( 'ACTIVITYPUB_USERNAME_REGEXP' ) || \define( 'ACTIVITYPUB_USERNAME_REGEXP', '(?:([A-Za-z0-9_-]+)@((?:[A-Za-z0-9_-]+\.)+[A-Za-z]+))' );
 	\defined( 'ACTIVITYPUB_CUSTOM_POST_CONTENT' ) || \define( 'ACTIVITYPUB_CUSTOM_POST_CONTENT', "<strong>[ap_title]</strong>\n\n[ap_content]\n\n[ap_hashtags]\n\n[ap_shortlink]" );
+	defined( 'ACTIVITYPUB_REST_NAMESPACE' ) || define( 'ACTIVITYPUB_REST_NAMESPACE', 'activitypub/1.0' );
 
 	\define( 'ACTIVITYPUB_PLUGIN_DIR', plugin_dir_path( __FILE__ ) );
 	\define( 'ACTIVITYPUB_PLUGIN_BASENAME', plugin_basename( __FILE__ ) );
@@ -120,12 +121,12 @@ function plugin_settings_link( $actions ) {
  */
 function add_rewrite_rules() {
 	if ( ! \class_exists( 'Webfinger' ) ) {
-		\add_rewrite_rule( '^.well-known/webfinger', 'index.php?rest_route=/activitypub/1.0/webfinger', 'top' );
+		\add_rewrite_rule( '^.well-known/webfinger', 'index.php?rest_route=/' . ACTIVITYPUB_REST_NAMESPACE . '/webfinger', 'top' );
 	}
 
 	if ( ! \class_exists( 'Nodeinfo' ) || ! (bool) \get_option( 'blog_public', 1 ) ) {
-		\add_rewrite_rule( '^.well-known/nodeinfo', 'index.php?rest_route=/activitypub/1.0/nodeinfo/discovery', 'top' );
-		\add_rewrite_rule( '^.well-known/x-nodeinfo2', 'index.php?rest_route=/activitypub/1.0/nodeinfo2', 'top' );
+		\add_rewrite_rule( '^.well-known/nodeinfo', 'index.php?rest_route=/' . ACTIVITYPUB_REST_NAMESPACE . '/nodeinfo/discovery', 'top' );
+		\add_rewrite_rule( '^.well-known/x-nodeinfo2', 'index.php?rest_route=/' . ACTIVITYPUB_REST_NAMESPACE . '/nodeinfo2', 'top' );
 	}
 
 	\add_rewrite_endpoint( 'activitypub', EP_AUTHORS | EP_PERMALINK | EP_PAGES );
diff --git a/includes/model/class-activity.php b/includes/model/class-activity.php
index b5372dc..ce99e87 100644
--- a/includes/model/class-activity.php
+++ b/includes/model/class-activity.php
@@ -148,7 +148,8 @@ class Activity {
 			$this->published = $object['published'];
 		}
 
-		$this->add_to( \get_rest_url( null, '/activitypub/1.0/users/' . intval( $post->get_post_author() ) . '/followers' ) );
+		$url = sprintf( '/%/users/%d/followers', ACTIVITYPUB_REST_NAMESPACE, intval( $post->get_post_author() ) );
+		$this->add_to( \get_rest_url( null, $url ) );
 
 		if ( isset( $this->object['attributedTo'] ) ) {
 			$this->actor = $this->object['attributedTo'];
diff --git a/includes/model/class-post.php b/includes/model/class-post.php
index ccb161c..022e390 100644
--- a/includes/model/class-post.php
+++ b/includes/model/class-post.php
@@ -142,7 +142,8 @@ class Post {
 	 */
 	public function __construct( $post ) {
 		$this->post = \get_post( $post );
-		$this->add_to( \get_rest_url( null, '/activitypub/1.0/users/' . intval( $this->get_post_author() ) . '/followers' ) );
+		$url = sprintf( '/%/users/%d/followers', ACTIVITYPUB_REST_NAMESPACE, intval( $post->get_post_author() ) );
+		$this->add_to( \get_rest_url( null, $url ) );
 	}
 
 	/**
diff --git a/includes/rest/class-followers.php b/includes/rest/class-followers.php
index 9a8b9b6..3abff6e 100644
--- a/includes/rest/class-followers.php
+++ b/includes/rest/class-followers.php
@@ -27,7 +27,7 @@ class Followers {
 	 */
 	public static function register_routes() {
 		\register_rest_route(
-			'activitypub/1.0',
+			ACTIVITYPUB_REST_NAMESPACE,
 			'/users/(?P<user_id>\d+)/followers',
 			array(
 				array(
@@ -78,7 +78,7 @@ class Followers {
 		$json->actor = \get_author_posts_url( $user_id );
 		$json->type = 'OrderedCollectionPage';
 
-		$json->partOf = \get_rest_url( null, "/activitypub/1.0/users/$user_id/followers" ); // phpcs:ignore
+		$json->partOf = \get_rest_url( null, sprintf( '/%s/users/%d/followers', ACTIVITYPUB_REST_NAMESPACE, $user_id ) ); // phpcs:ignore
 		$json->first = $json->partOf; // phpcs:ignore
 		$json->totalItems = FollowerCollection::count_followers( $user_id ); // phpcs:ignore
 		$json->orderedItems = FollowerCollection::get_followers( $user_id, ARRAY_N ); // phpcs:ignore
diff --git a/includes/rest/class-following.php b/includes/rest/class-following.php
index 52a95e7..2606df4 100644
--- a/includes/rest/class-following.php
+++ b/includes/rest/class-following.php
@@ -21,7 +21,7 @@ class Following {
 	 */
 	public static function register_routes() {
 		\register_rest_route(
-			'activitypub/1.0',
+			ACTIVITYPUB_REST_NAMESPACE,
 			'/users/(?P<user_id>\d+)/following',
 			array(
 				array(
@@ -72,7 +72,7 @@ class Following {
 		$json->actor = \get_author_posts_url( $user_id );
 		$json->type = 'OrderedCollectionPage';
 
-		$json->partOf = \get_rest_url( null, "/activitypub/1.0/users/$user_id/following" ); // phpcs:ignore
+		$json->partOf = \get_rest_url( null, sprintf( '/%s/users/%d/following', ACTIVITYPUB_REST_NAMESPACE, $user_id ) ); // phpcs:ignore
 		$json->totalItems = 0; // phpcs:ignore
 		$json->orderedItems = apply_filters( 'activitypub_following', array(), $user ); // phpcs:ignore
 
diff --git a/includes/rest/class-inbox.php b/includes/rest/class-inbox.php
index 5a23d02..16735df 100644
--- a/includes/rest/class-inbox.php
+++ b/includes/rest/class-inbox.php
@@ -26,7 +26,7 @@ class Inbox {
 	 */
 	public static function register_routes() {
 		\register_rest_route(
-			'activitypub/1.0',
+			ACTIVITYPUB_REST_NAMESPACE,
 			'/inbox',
 			array(
 				array(
@@ -39,7 +39,7 @@ class Inbox {
 		);
 
 		\register_rest_route(
-			'activitypub/1.0',
+			ACTIVITYPUB_REST_NAMESPACE,
 			'/users/(?P<user_id>\d+)/inbox',
 			array(
 				array(
@@ -108,7 +108,7 @@ class Inbox {
 		$json->id = \home_url( \add_query_arg( null, null ) );
 		$json->generator = 'http://wordpress.org/?v=' . \get_bloginfo_rss( 'version' );
 		$json->type = 'OrderedCollectionPage';
-		$json->partOf = \get_rest_url( null, "/activitypub/1.0/users/$user_id/inbox" ); // phpcs:ignore
+		$json->partOf = \get_rest_url( null, sprintf( '/%s/users/%d/inbox', ACTIVITYPUB_REST_NAMESPACE, $user_id ) ); // phpcs:ignore
 
 		$json->totalItems = 0; // phpcs:ignore
 
diff --git a/includes/rest/class-nodeinfo.php b/includes/rest/class-nodeinfo.php
index 980c24b..bafa7e4 100644
--- a/includes/rest/class-nodeinfo.php
+++ b/includes/rest/class-nodeinfo.php
@@ -23,7 +23,7 @@ class Nodeinfo {
 	 */
 	public static function register_routes() {
 		\register_rest_route(
-			'activitypub/1.0',
+			ACTIVITYPUB_REST_NAMESPACE,
 			'/nodeinfo/discovery',
 			array(
 				array(
@@ -35,7 +35,7 @@ class Nodeinfo {
 		);
 
 		\register_rest_route(
-			'activitypub/1.0',
+			ACTIVITYPUB_REST_NAMESPACE,
 			'/nodeinfo',
 			array(
 				array(
@@ -47,7 +47,7 @@ class Nodeinfo {
 		);
 
 		\register_rest_route(
-			'activitypub/1.0',
+			ACTIVITYPUB_REST_NAMESPACE,
 			'/nodeinfo2',
 			array(
 				array(
@@ -173,7 +173,7 @@ class Nodeinfo {
 		$discovery['links'] = array(
 			array(
 				'rel' => 'http://nodeinfo.diaspora.software/ns/schema/2.0',
-				'href' => \get_rest_url( null, 'activitypub/1.0/nodeinfo' ),
+				'href' => \get_rest_url( null, ACTIVITYPUB_REST_NAMESPACE . '/nodeinfo' ),
 			),
 		);
 
diff --git a/includes/rest/class-ostatus.php b/includes/rest/class-ostatus.php
index 45ff901..415d502 100644
--- a/includes/rest/class-ostatus.php
+++ b/includes/rest/class-ostatus.php
@@ -14,7 +14,7 @@ class Ostatus {
 	 */
 	public static function register_routes() {
 		\register_rest_route(
-			'activitypub/1.0',
+			ACTIVITYPUB_REST_NAMESPACE,
 			'/ostatus/remote-follow',
 			array(
 				array(
diff --git a/includes/rest/class-outbox.php b/includes/rest/class-outbox.php
index 905dfd5..5ae8e50 100644
--- a/includes/rest/class-outbox.php
+++ b/includes/rest/class-outbox.php
@@ -21,7 +21,7 @@ class Outbox {
 	 */
 	public static function register_routes() {
 		\register_rest_route(
-			'activitypub/1.0',
+			ACTIVITYPUB_REST_NAMESPACE,
 			'/users/(?P<user_id>\d+)/outbox',
 			array(
 				array(
@@ -72,7 +72,7 @@ class Outbox {
 		$json->generator = 'http://wordpress.org/?v=' . \get_bloginfo_rss( 'version' );
 		$json->actor = \get_author_posts_url( $user_id );
 		$json->type = 'OrderedCollectionPage';
-		$json->partOf = \get_rest_url( null, "/activitypub/1.0/users/$user_id/outbox" ); // phpcs:ignore
+		$json->partOf = \get_rest_url( null, sprintf( '/%s/users/%d/outbox', ACTIVITYPUB_REST_NAMESPACE, $user_id ) ); // phpcs:ignore
 		$json->totalItems = 0; // phpcs:ignore
 
 		// phpcs:ignore
diff --git a/includes/rest/class-webfinger.php b/includes/rest/class-webfinger.php
index 10dcfa4..f75a3f7 100644
--- a/includes/rest/class-webfinger.php
+++ b/includes/rest/class-webfinger.php
@@ -25,7 +25,7 @@ class Webfinger {
 	 */
 	public static function register_routes() {
 		\register_rest_route(
-			'activitypub/1.0',
+			ACTIVITYPUB_REST_NAMESPACE,
 			'/webfinger',
 			array(
 				array(
diff --git a/templates/author-json.php b/templates/author-json.php
index 3b355b9..090920d 100644
--- a/templates/author-json.php
+++ b/templates/author-json.php
@@ -28,10 +28,10 @@ if ( \has_header_image() ) {
 	);
 }
 
-$json->inbox = \get_rest_url( null, "/activitypub/1.0/users/$author_id/inbox" );
-$json->outbox = \get_rest_url( null, "/activitypub/1.0/users/$author_id/outbox" );
-$json->followers = \get_rest_url( null, "/activitypub/1.0/users/$author_id/followers" );
-$json->following = \get_rest_url( null, "/activitypub/1.0/users/$author_id/following" );
+$json->inbox = \get_rest_url( null, sprintf( '/%s/users/%d/inbox', ACTIVITYPUB_REST_NAMESPACE, $author_id ) );
+$json->outbox = \get_rest_url( null, sprintf( '/%s/users/%d/outbox', ACTIVITYPUB_REST_NAMESPACE, $author_id ) );
+$json->followers = \get_rest_url( null, sprintf( '/%s/users/%d/followers', ACTIVITYPUB_REST_NAMESPACE, $author_id ) );
+$json->following = \get_rest_url( null, sprintf( '/%s/users/%d/following', ACTIVITYPUB_REST_NAMESPACE, $author_id ) );
 
 $json->manuallyApprovesFollowers = \apply_filters( 'activitypub_json_manually_approves_followers', \__return_false() ); // phpcs:ignore
 
diff --git a/templates/blog-json.php b/templates/blog-json.php
index 4a1efc8..38f0406 100644
--- a/templates/blog-json.php
+++ b/templates/blog-json.php
@@ -27,10 +27,12 @@ if ( \has_header_image() ) {
 	);
 }
 
-$json->inbox = \get_rest_url( null, '/activitypub/1.0/blog/inbox' );
-$json->outbox = \get_rest_url( null, '/activitypub/1.0/blog/outbox' );
-$json->followers = \get_rest_url( null, '/activitypub/1.0/blog/followers' );
-$json->following = \get_rest_url( null, '/activitypub/1.0/blog/following' );
+$blog_base = sprintf( '/%s/blog/', ACTIVITYPUB_REST_NAMESPACE );
+
+$json->inbox = \get_rest_url( null, $blog_base . 'inbox' );
+$json->outbox = \get_rest_url( null, $blog_base . 'outbox' );
+$json->followers = \get_rest_url( null, $blog_base . 'followers' );
+$json->following = \get_rest_url( null, $blog_base . 'following' );
 
 $json->manuallyApprovesFollowers = \apply_filters( 'activitypub_json_manually_approves_followers', \__return_false() ); // phpcs:ignore
 
diff --git a/tests/test-class-activitypub-activity.php b/tests/test-class-activitypub-activity.php
index 7fe6551..b18c6ab 100644
--- a/tests/test-class-activitypub-activity.php
+++ b/tests/test-class-activitypub-activity.php
@@ -22,7 +22,7 @@ class Test_Activitypub_Activity extends WP_UnitTestCase {
 		$activitypub_activity = new \Activitypub\Model\Activity( 'Create' );
 		$activitypub_activity->from_post( $activitypub_post );
 
-		$this->assertContains( \get_rest_url( null, '/activitypub/1.0/users/1/followers' ), $activitypub_activity->get_to() );
+		$this->assertContains( \get_rest_url( null, '/' . ACTIVITYPUB_REST_NAMESPACE . '/users/1/followers' ), $activitypub_activity->get_to() );
 		$this->assertContains( 'https://example.com/alex', $activitypub_activity->get_cc() );
 
 		remove_all_filters( 'activitypub_extract_mentions' );