diff --git a/Normalizer/ArrayDenormalizer.php b/Normalizer/ArrayDenormalizer.php
index 65b1c2e82..19baa490c 100644
--- a/Normalizer/ArrayDenormalizer.php
+++ b/Normalizer/ArrayDenormalizer.php
@@ -46,7 +46,7 @@ public function denormalize($data, $type, $format = null, array $context = [])
         if (!\is_array($data)) {
             throw new InvalidArgumentException('Data expected to be an array, '.\gettype($data).' given.');
         }
-        if ('[]' !== substr($type, -2)) {
+        if (!str_ends_with($type, '[]')) {
             throw new InvalidArgumentException('Unsupported class: '.$type);
         }
 
@@ -74,7 +74,7 @@ public function supportsDenormalization($data, $type, $format = null, array $con
             throw new BadMethodCallException(sprintf('The serializer needs to be set to allow "%s()" to be used.', __METHOD__));
         }
 
-        return '[]' === substr($type, -2)
+        return str_ends_with($type, '[]')
             && $this->serializer->supportsDenormalization($data, substr($type, 0, -2), $format, $context);
     }
 
diff --git a/Tests/Normalizer/AbstractObjectNormalizerTest.php b/Tests/Normalizer/AbstractObjectNormalizerTest.php
index 273a42aac..d1c1d1cbe 100644
--- a/Tests/Normalizer/AbstractObjectNormalizerTest.php
+++ b/Tests/Normalizer/AbstractObjectNormalizerTest.php
@@ -484,7 +484,7 @@ public function denormalize($data, $type, $format = null, array $context = [])
      */
     public function supportsDenormalization($data, $type, $format = null, array $context = []): bool
     {
-        return '[]' === substr($type, -2)
+        return str_ends_with($type, '[]')
             && $this->serializer->supportsDenormalization($data, substr($type, 0, -2), $format, $context);
     }
 
diff --git a/composer.json b/composer.json
index 075896e47..324c30edf 100644
--- a/composer.json
+++ b/composer.json
@@ -17,7 +17,8 @@
     ],
     "require": {
         "php": ">=7.1.3",
-        "symfony/polyfill-ctype": "~1.8"
+        "symfony/polyfill-ctype": "~1.8",
+        "symfony/polyfill-php80": "^1.16"
     },
     "require-dev": {
         "doctrine/annotations": "^1.10.4",