diff --git a/load.php b/load.php
index 23f8503463..f3c8f5e987 100644
--- a/load.php
+++ b/load.php
@@ -5,7 +5,7 @@
  * Description: Performance plugin from the WordPress Performance Team, which is a collection of standalone performance modules.
  * Requires at least: 6.3
  * Requires PHP: 7.0
- * Version: 2.8.0
+ * Version: 2.9.0
  * Author: WordPress Performance Team
  * Author URI: https://make.wordpress.org/performance/
  * License: GPLv2 or later
@@ -19,7 +19,7 @@
 	exit; // Exit if accessed directly.
 }
 
-define( 'PERFLAB_VERSION', '2.8.0' );
+define( 'PERFLAB_VERSION', '2.9.0' );
 define( 'PERFLAB_MAIN_FILE', __FILE__ );
 define( 'PERFLAB_PLUGIN_DIR_PATH', plugin_dir_path( PERFLAB_MAIN_FILE ) );
 define( 'PERFLAB_MODULES_SETTING', 'perflab_modules_settings' );
@@ -207,7 +207,7 @@ function perflab_is_valid_module( $module ) {
  * This attribute is then used in {@see perflab_render_generator()}.
  *
  * @since 1.1.0
- * @since n.e.x.t The generator tag now includes the active standalone plugin slugs.
+ * @since 2.9.0 The generator tag now includes the active standalone plugin slugs.
  */
 function perflab_get_generator_content() {
 	$active_and_valid_modules = array_filter( perflab_get_active_modules(), 'perflab_is_valid_module' );
@@ -312,7 +312,7 @@ function perflab_get_standalone_plugins_constants() {
 /**
  * Gets the standalone plugin constants used for each available standalone plugin, or module with a standalone plugin.
  *
- * @since n.e.x.t
+ * @since 2.9.0
  *
  * @param string $source Optional. Either 'plugins' or 'modules'. Default 'plugins'.
  * @return array<string, string> Map of plugin slug / module path and the version constant used.
diff --git a/readme.txt b/readme.txt
index 25833cd4bb..931660bf2e 100644
--- a/readme.txt
+++ b/readme.txt
@@ -4,7 +4,7 @@ Contributors:      wordpressdotorg
 Requires at least: 6.3
 Tested up to:      6.4
 Requires PHP:      7.0
-Stable tag:        2.8.0
+Stable tag:        2.9.0
 License:           GPLv2 or later
 License URI:       https://www.gnu.org/licenses/gpl-2.0.html
 Tags:              performance, images, javascript, site health, measurement, object caching
@@ -79,6 +79,20 @@ By default, the WebP Uploads module will only generate WebP versions of the imag
 
 == Changelog ==
 
+= 2.9.0 =
+
+**Features**
+
+* Infrastructure: Add standalone plugin version constants for auto-sizes and speculation-rules. ([958](https://github.com/WordPress/performance/pull/958))
+
+**Enhancements**
+
+* Infrastructure: Include standalone plugin slugs in generator tag. ([949](https://github.com/WordPress/performance/pull/949))
+
+**Bug Fixes**
+
+* Infrastructure: Sanitize metric name for `Server-Timing` header. ([957](https://github.com/WordPress/performance/pull/957))
+
 = 2.8.0 =
 
 **Features**