diff --git a/composer.json b/composer.json
index 790a1c48e..60ba5155f 100644
--- a/composer.json
+++ b/composer.json
@@ -11,7 +11,7 @@
     },
     "require-dev": {
         "squizlabs/php_codesniffer": "^2.2 || ^3.0.2",
-        "yoast/phpunit-polyfills": "^1.0.1"
+        "yoast/phpunit-polyfills": "^1.0"
     },
     "prefer-stable" : true,
     "minimum-stability": "dev",
diff --git a/composer.lock b/composer.lock
index 5dac8f50d..b07661157 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "9a50d78655731555071e552968158d04",
+    "content-hash": "d992085bca26ce8848677373c5cc0080",
     "packages": [
         {
             "name": "kornrunner/blurhash",
@@ -2214,5 +2214,5 @@
     "prefer-lowest": false,
     "platform": [],
     "platform-dev": [],
-    "plugin-api-version": "2.1.0"
+    "plugin-api-version": "2.2.0"
 }
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
index 106b82f00..26935e2d2 100644
--- a/tests/bootstrap.php
+++ b/tests/bootstrap.php
@@ -29,8 +29,8 @@ function _manually_load_plugin() {
 tests_add_filter( 'muplugins_loaded', '_manually_load_plugin' );
 
 // Start up the WP testing environment.
+require_once dirname( dirname( __FILE__ ) ) . '/src/vendor/autoload.php';
 require $_tests_dir . '/includes/bootstrap.php';
-
 require_once(__DIR__ . '/factories/class-tainacan-entity-factory.php');
 require_once( __DIR__ . '/factories/class-tainacan-metadatum-factory.php' );
 require_once(__DIR__ . '/factories/class-tainacan-filter-factory.php');