diff --git a/.github/workflows/unit-tests.yml b/.github/workflows/unit-tests.yml
index be228a1885..74c65fe541 100644
--- a/.github/workflows/unit-tests.yml
+++ b/.github/workflows/unit-tests.yml
@@ -79,6 +79,11 @@ jobs:
             wp-env-args: "--config plugin-directory/.wp-env.test.json"
             container: tests-cli
             plugin-name: plugin-directory
+          - name: Theme Directory
+            working-directory: environments
+            wp-env-args: "--config theme-directory/.wp-env.test.json"
+            container: tests-cli
+            plugin-name: theme-directory
     steps:
       - uses: actions/checkout@v4
 
diff --git a/environments/theme-directory/.wp-env.test.json b/environments/theme-directory/.wp-env.test.json
new file mode 100644
index 0000000000..1d7f9ca999
--- /dev/null
+++ b/environments/theme-directory/.wp-env.test.json
@@ -0,0 +1,10 @@
+{
+	"core": "WordPress/WordPress#master",
+	"phpVersion": "8.4",
+	"plugins": [
+		"../wordpress.org/public_html/wp-content/plugins/theme-directory"
+	],
+	"lifecycleScripts": {
+		"afterStart": "bash theme-directory/bin/after-start-test.sh"
+	}
+}
diff --git a/environments/theme-directory/bin/after-start-test.sh b/environments/theme-directory/bin/after-start-test.sh
new file mode 100755
index 0000000000..889be08e46
--- /dev/null
+++ b/environments/theme-directory/bin/after-start-test.sh
@@ -0,0 +1,12 @@
+#!/bin/bash
+#
+# Runs after wp-env start for the test environment.
+# Installs PHPUnit 11 and Yoast polyfills in the test container.
+#
+
+CONFIG="--config theme-directory/.wp-env.test.json"
+RUN="npx wp-env $CONFIG run tests-cli"
+
+echo "Installing PHPUnit 11 and polyfills..."
+$RUN composer global require -W phpunit/phpunit:^11.0 2>&1
+$RUN composer require --dev yoast/phpunit-polyfills:^4.0 --working-dir=/wordpress-phpunit 2>&1
diff --git a/wordpress.org/public_html/wp-content/plugins/theme-directory/class-themes-api.php b/wordpress.org/public_html/wp-content/plugins/theme-directory/class-themes-api.php
index 2a0f36b6c6..52ccaa37a4 100644
--- a/wordpress.org/public_html/wp-content/plugins/theme-directory/class-themes-api.php
+++ b/wordpress.org/public_html/wp-content/plugins/theme-directory/class-themes-api.php
@@ -866,7 +866,8 @@ public function fill_theme( $theme ) {
 		if ( $this->fields['versions'] ) {
 			$phil->versions = array();
 
-			foreach ( array_keys( get_post_meta( $theme->ID, '_status', true ) ) as $version ) {
+			$status = get_post_meta( $theme->ID, '_status', true );
+			foreach ( is_array( $status ) ? array_keys( $status ) : array() as $version ) {
 				$phil->versions[ $version ] = $repo_package->download_url( $version );
 			}
 		}
diff --git a/wordpress.org/public_html/wp-content/plugins/theme-directory/class-wporg-themes-upload.php b/wordpress.org/public_html/wp-content/plugins/theme-directory/class-wporg-themes-upload.php
index 7e9fdd3b7d..5526d4d553 100644
--- a/wordpress.org/public_html/wp-content/plugins/theme-directory/class-wporg-themes-upload.php
+++ b/wordpress.org/public_html/wp-content/plugins/theme-directory/class-wporg-themes-upload.php
@@ -787,7 +787,7 @@ protected function import( $args = array() ) {
 				}
 
 				if ( $is_new_upload && $this->theme_post ) {
-					wp_delete_post( $this->theme_post->ID, true );
+					$this->delete_theme_post();
 				}
 
 				return new WP_Error(
@@ -1315,7 +1315,7 @@ public function create_or_update_trac_ticket() {
 		 * the superseded version is simply demoted to `old`.
 		 */
 		if ( in_array( $prev_status, [ 'new', 'approved' ], true ) ) {
-			$ticket_id = (int) $this->theme_post->_ticket_id[ $this->theme_post->max_version ];
+			$ticket_id = (int) ( $this->theme_post->_ticket_id[ $this->theme_post->max_version ] ?? 0 );
 			$ticket    = $this->trac->ticket_get( $ticket_id );
 
 			// Make sure the ticket has not yet been resolved.
@@ -1449,6 +1449,24 @@ public function create_or_update_theme_post() {
 		}
 	}
 
+	/**
+	 * Deletes the theme post.
+	 *
+	 * Used to clean up a freshly created post when a new upload fails.
+	 * Temporarily detaches the fail-safe that prevents repopackages from
+	 * being deleted, which would otherwise wp_die() before the post is
+	 * removed, leaving an orphaned post without versioned meta behind.
+	 *
+	 * @return WP_Post|false|null Post data on success, false or null on failure.
+	 */
+	public function delete_theme_post() {
+		remove_filter( 'before_delete_post', 'wporg_theme_no_delete_repopackage' );
+		$result = wp_delete_post( $this->theme_post->ID, true );
+		add_filter( 'before_delete_post', 'wporg_theme_no_delete_repopackage' );
+
+		return $result;
+	}
+
 	/**
 	 * Add theme files to SVN.
 	 * 
@@ -1752,7 +1770,7 @@ public function get_all_files( $dir ) {
 	 * @return WP_Theme
 	 */
 	public function populate_post_with_meta( $theme ) {
-		foreach ( get_post_custom_keys( $theme->ID ) as $meta_key ) {
+		foreach ( (array) get_post_custom_keys( $theme->ID ) as $meta_key ) {
 			$theme->$meta_key = get_post_meta( $theme->ID, $meta_key, true );
 
 			if ( is_array( $theme->$meta_key ) ) {
@@ -1761,7 +1779,7 @@ public function populate_post_with_meta( $theme ) {
 		}
 
 		// Save the highest recorded version number.
-		$uploaded_versions  = array_keys( $theme->_status );
+		$uploaded_versions  = is_array( $theme->_status ) ? array_keys( $theme->_status ) : array();
 		$theme->max_version = end( $uploaded_versions );
 
 		return $theme;
diff --git a/wordpress.org/public_html/wp-content/plugins/theme-directory/phpunit.xml b/wordpress.org/public_html/wp-content/plugins/theme-directory/phpunit.xml
new file mode 100644
index 0000000000..71b6007751
--- /dev/null
+++ b/wordpress.org/public_html/wp-content/plugins/theme-directory/phpunit.xml
@@ -0,0 +1,12 @@
+<phpunit
+	bootstrap="tests/bootstrap.php"
+	backupGlobals="false"
+	colors="true"
+	>
+	<testsuites>
+		<testsuite name="theme-directory">
+			<directory suffix=".php">tests/</directory>
+			<exclude>tests/bootstrap.php</exclude>
+		</testsuite>
+	</testsuites>
+</phpunit>
diff --git a/wordpress.org/public_html/wp-content/plugins/theme-directory/tests/Missing_Status_Meta_Test.php b/wordpress.org/public_html/wp-content/plugins/theme-directory/tests/Missing_Status_Meta_Test.php
new file mode 100644
index 0000000000..a5e20261dc
--- /dev/null
+++ b/wordpress.org/public_html/wp-content/plugins/theme-directory/tests/Missing_Status_Meta_Test.php
@@ -0,0 +1,185 @@
+<?php
+/**
+ * Tests for handling repopackage posts that are missing the `_status` post meta.
+ *
+ * A hard failure during WPORG_Themes_Upload::import() can leave a repopackage
+ * post without `_status` (and `_ticket_id`) meta. WP_Post::__get() returns an
+ * empty string for missing meta, which used to fatal on PHP 8 wherever an
+ * array was assumed.
+ *
+ * @package theme-directory
+ */
+
+use PHPUnit\Framework\TestCase;
+
+/**
+ * @group upload
+ * @group themes-api
+ */
+class Missing_Status_Meta_Test extends TestCase {
+
+	/**
+	 * IDs of posts created during a test, deleted again on teardown.
+	 *
+	 * @var array
+	 */
+	protected $post_ids = array();
+
+	/**
+	 * Deletes the posts created during the test.
+	 */
+	protected function tearDown(): void {
+		/*
+		 * The plugin prevents repopackages from being deleted; detach that
+		 * specific guard while cleaning up the fixture posts.
+		 */
+		remove_filter( 'before_delete_post', 'wporg_theme_no_delete_repopackage' );
+		foreach ( $this->post_ids as $post_id ) {
+			wp_delete_post( $post_id, true );
+		}
+		add_filter( 'before_delete_post', 'wporg_theme_no_delete_repopackage' );
+
+		$this->post_ids = array();
+
+		parent::tearDown();
+	}
+
+	/**
+	 * Creates a repopackage post.
+	 *
+	 * @param array $meta Optional. Post meta to add to the post.
+	 * @return WP_Post The created post.
+	 */
+	protected function create_repopackage( $meta = array() ) {
+		$post_id = wp_insert_post( array(
+			'post_type'   => 'repopackage',
+			'post_status' => 'publish',
+			'post_title'  => 'Test Theme',
+			'post_name'   => 'test-theme',
+			'post_author' => 1,
+		) );
+
+		$this->post_ids[] = $post_id;
+
+		foreach ( $meta as $key => $value ) {
+			add_post_meta( $post_id, $key, $value );
+		}
+
+		return get_post( $post_id );
+	}
+
+	/**
+	 * A post with no meta at all should not fatal and yield no max_version.
+	 */
+	public function test_populate_post_with_meta_without_any_meta() {
+		$post   = $this->create_repopackage();
+		$upload = new WPORG_Themes_Upload();
+
+		$theme = $upload->populate_post_with_meta( $post );
+
+		$this->assertFalse( $theme->max_version );
+	}
+
+	/**
+	 * A post with versioned meta but no `_status` (an orphan from a failed
+	 * import) should not fatal and yield no max_version.
+	 */
+	public function test_populate_post_with_meta_without_status_meta() {
+		$post   = $this->create_repopackage( array(
+			'_requires' => array( '1.0.0' => '5.0' ),
+			'_author'   => array( '1.0.0' => 'Test Author' ),
+		) );
+		$upload = new WPORG_Themes_Upload();
+
+		$theme = $upload->populate_post_with_meta( $post );
+
+		$this->assertFalse( $theme->max_version );
+		$this->assertSame( array( '1.0.0' => '5.0' ), $theme->_requires );
+	}
+
+	/**
+	 * A post with valid `_status` meta should yield the highest version.
+	 */
+	public function test_populate_post_with_meta_with_status_meta() {
+		$post   = $this->create_repopackage( array(
+			'_status' => array(
+				'1.1'  => 'old',
+				'1.0'  => 'old',
+				'1.10' => 'live',
+			),
+		) );
+		$upload = new WPORG_Themes_Upload();
+
+		$theme = $upload->populate_post_with_meta( $post );
+
+		$this->assertSame( '1.10', $theme->max_version );
+	}
+
+	/**
+	 * Cleaning up a failed new upload should delete the theme post despite
+	 * the fail-safe against repopackage deletion, and restore the fail-safe
+	 * afterwards.
+	 */
+	public function test_delete_theme_post_bypasses_deletion_fail_safe() {
+		$post   = $this->create_repopackage();
+		$upload = new WPORG_Themes_Upload();
+
+		$upload->theme_post = $post;
+		$result             = $upload->delete_theme_post();
+
+		$this->assertNotEmpty( $result );
+		$this->assertNull( get_post( $post->ID ) );
+		$this->assertSame( 10, has_filter( 'before_delete_post', 'wporg_theme_no_delete_repopackage' ) );
+	}
+
+	/**
+	 * The themes API should return an empty `versions` array for a published
+	 * theme missing the `_status` meta, rather than fataling.
+	 */
+	public function test_theme_information_versions_without_status_meta() {
+		$this->create_repopackage();
+
+		$api = new Themes_API(
+			'theme_information',
+			array(
+				'slug'   => 'test-theme',
+				'fields' => array(
+					'versions'       => true,
+					'downloaded'     => false,
+					'screenshot_url' => false,
+				),
+			)
+		);
+
+		$this->assertObjectNotHasProperty( 'error', $api->response );
+		$this->assertSame( array(), $api->response->versions );
+	}
+
+	/**
+	 * The themes API should return all versions for a theme with valid
+	 * `_status` meta.
+	 */
+	public function test_theme_information_versions_with_status_meta() {
+		$this->create_repopackage( array(
+			'_status' => array(
+				'1.0' => 'old',
+				'1.1' => 'live',
+			),
+		) );
+
+		$api = new Themes_API(
+			'theme_information',
+			array(
+				'slug'   => 'test-theme',
+				'fields' => array(
+					'versions'       => true,
+					'downloaded'     => false,
+					'screenshot_url' => false,
+				),
+			)
+		);
+
+		$this->assertObjectNotHasProperty( 'error', $api->response );
+		$this->assertSame( array( '1.0', '1.1' ), array_keys( $api->response->versions ) );
+	}
+}
diff --git a/wordpress.org/public_html/wp-content/plugins/theme-directory/tests/bootstrap.php b/wordpress.org/public_html/wp-content/plugins/theme-directory/tests/bootstrap.php
new file mode 100644
index 0000000000..e232641bc1
--- /dev/null
+++ b/wordpress.org/public_html/wp-content/plugins/theme-directory/tests/bootstrap.php
@@ -0,0 +1,60 @@
+<?php
+/**
+ * PHPUnit bootstrap file.
+ *
+ * @package theme-directory
+ */
+
+namespace WordPressdotorg\Theme_Directory\Tests;
+
+if ( 'cli' !== php_sapi_name() ) {
+	return;
+}
+
+$_tests_dir = getenv( 'WP_TESTS_DIR' );
+
+if ( ! $_tests_dir ) {
+	$pos = stripos( __FILE__, '/src/wp-content/plugins/' );
+
+	if ( false !== $pos ) {
+		// Installed in a src checkout.
+		$_tests_dir = substr( __FILE__, 0, $pos ) . '/tests/phpunit/';
+	} elseif ( file_exists( '/wordpress-phpunit/includes/functions.php' ) ) {
+		// wp-env test directory.
+		$_tests_dir = '/wordpress-phpunit/';
+	} else {
+		// Assume a temp directory path.
+		$_tests_dir = rtrim( sys_get_temp_dir(), '/\\' ) . '/wordpress-tests-lib/tests/phpunit/';
+	}
+}
+
+if ( ! file_exists( $_tests_dir . '/includes/functions.php' ) ) {
+	fwrite( STDERR, "Could not find {$_tests_dir}/includes/functions.php\n" );
+	exit( 1 );
+}
+
+// Set polyfills path if available (required by WP test suite).
+if ( ! defined( 'WP_TESTS_PHPUNIT_POLYFILLS_PATH' ) && file_exists( $_tests_dir . '/vendor/yoast/phpunit-polyfills' ) ) {
+	define( 'WP_TESTS_PHPUNIT_POLYFILLS_PATH', $_tests_dir . '/vendor/yoast/phpunit-polyfills' );
+}
+
+// Give access to tests_add_filter() function.
+require_once $_tests_dir . '/includes/functions.php';
+
+/**
+ * Manually load the plugin being tested.
+ */
+function manually_load_plugin() {
+	require_once dirname( __DIR__ ) . '/theme-directory.php';
+
+	/*
+	 * These classes are only included on demand at runtime (on upload, or when
+	 * serving an API request); load them up front for the tests.
+	 */
+	require_once dirname( __DIR__ ) . '/class-wporg-themes-upload.php';
+	require_once dirname( __DIR__ ) . '/class-themes-api.php';
+}
+tests_add_filter( 'muplugins_loaded', __NAMESPACE__ . '\manually_load_plugin' );
+
+// Start up the WP testing environment.
+require $_tests_dir . '/includes/bootstrap.php';