diff --git a/.circleci/config.yml b/.circleci/config.yml
index 21d676d18528a1f42d4e40ab4734c19a313fb2ef..1e5ca144daa07c5486351dae6c18cff2572bd78e 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -6,26 +6,16 @@ workflows:
       - test:
           matrix:
             parameters:
-              php: ["8.0", "8.1"]
-              drupal-version: ["9.4.x", "9.5.x", "10.0.x", "10.1.x"]
-            exclude:
-            - php: "8.0"
-              drupal-version: "10.0.x"
-            - php: "8.0"
-              drupal-version: "10.1.x"
+              php: ["8.1"]
+              drupal-version: ["10.0.x", "10.1.x"]
   # Run nightly tests every day 8 AM.
   nightly:
     jobs:
     - test:
         matrix:
           parameters:
-            php: ["8.0", "8.1"]
-            drupal-version: ["9.4.x", "9.5.x", "10.0.x", "10.1.x"]
-          exclude:
-          - php: "8.0"
-            drupal-version: "10.0.x"
-          - php: "8.0"
-            drupal-version: "10.1.x"
+            php: ["8.1"]
+            drupal-version: ["10.0.x", "10.1.x"]
     triggers:
     - schedule:
         # Weekday (22=10pm UTC). Evaluates to 8am AEST.
diff --git a/composer.json b/composer.json
index f6fc1a55f4fe32c0fbacc8ef8c881ed96ab35f05..66dcd167b402f6a73915b8b2d2420fd006c7b518 100644
--- a/composer.json
+++ b/composer.json
@@ -23,8 +23,8 @@
   "license": "GPL-2.0-or-later",
   "minimum-stability": "dev",
   "require": {
-    "php": ">=8.0",
-    "drupal/core": "^9.3 || ^10"
+    "php": ">=8.1",
+    "drupal/core": "^10"
   },
   "require-dev": {
     "mglaman/phpstan-drupal": "^1.1",
diff --git a/dynamic_entity_reference.info.yml b/dynamic_entity_reference.info.yml
index ee18e8e9b2194f82f1fb1481e44a693b986603e1..64750a016aa695f0bca17bea5a2421ca8342cc67 100644
--- a/dynamic_entity_reference.info.yml
+++ b/dynamic_entity_reference.info.yml
@@ -2,8 +2,8 @@ name: Dynamic Entity Reference
 type: module
 description: 'Provides an entity reference field that can reference multiple entity types.'
 package: Field types
-core_version_requirement: ^9.3 || ^10
-php: 8.0
+core_version_requirement: ^10
+php: 8.1
 dependencies:
   - drupal:field
 test_dependencies:
diff --git a/src/Normalizer/DynamicEntityReferenceItemNormalizer.php b/src/Normalizer/DynamicEntityReferenceItemNormalizer.php
index 538334f30596d5609991ea23b546734192d435ee..85cc428a0016dee5dc7f2fa9613436f212c40296 100644
--- a/src/Normalizer/DynamicEntityReferenceItemNormalizer.php
+++ b/src/Normalizer/DynamicEntityReferenceItemNormalizer.php
@@ -20,7 +20,7 @@ class DynamicEntityReferenceItemNormalizer extends EntityReferenceItemNormalizer
   /**
    * {@inheritdoc}
    */
-  public function normalize($field_item, $format = NULL, array $context = []): array|string|int|float|bool|\ArrayObject|NULL {
+  public function normalize($field_item, $format = NULL, array $context = []) {
     $normalized = parent::normalize($field_item, $format, $context);
     $normalized['target_type'] = $field_item->target_type;
     return $normalized;
diff --git a/tests/modules/dynamic_entity_reference_entity_test/dynamic_entity_reference_entity_test.info.yml b/tests/modules/dynamic_entity_reference_entity_test/dynamic_entity_reference_entity_test.info.yml
index b2ac181d6b4369d1cbdaedf5fcfdae35aa2b8a54..fa602f386b368e4ea7d0bc93366d2d42f6c99e4e 100644
--- a/tests/modules/dynamic_entity_reference_entity_test/dynamic_entity_reference_entity_test.info.yml
+++ b/tests/modules/dynamic_entity_reference_entity_test/dynamic_entity_reference_entity_test.info.yml
@@ -2,8 +2,8 @@ name: 'Dynamic Entity Reference Entity Test'
 type: module
 description: 'Provides base fields for dynamic_entity_reference tests of entity_test entity type.'
 package: Testing
-core_version_requirement: ^9.3 || ^10
-php: 8.0
+core_version_requirement: ^10
+php: 8.1
 hidden: TRUE
 dependencies:
   - dynamic_entity_reference:dynamic_entity_reference
diff --git a/tests/modules/dynamic_entity_reference_test_entity_provider/dynamic_entity_reference_test_entity_provider.info.yml b/tests/modules/dynamic_entity_reference_test_entity_provider/dynamic_entity_reference_test_entity_provider.info.yml
index 8090086c7ea374bf1bf8e90886c1855cdd8a781d..e0d25dd52acdf497c532bb4f886de49a8d46b8ad 100644
--- a/tests/modules/dynamic_entity_reference_test_entity_provider/dynamic_entity_reference_test_entity_provider.info.yml
+++ b/tests/modules/dynamic_entity_reference_test_entity_provider/dynamic_entity_reference_test_entity_provider.info.yml
@@ -2,8 +2,8 @@ name: 'Dynamic Entity Reference Entity Provider'
 type: module
 description: 'A provider of an entity type.'
 package: Testing
-core_version_requirement: ^9.3 || ^10
-php: 8.0
+core_version_requirement: ^10
+php: 8.1
 hidden: TRUE
 dependencies:
   - dynamic_entity_reference:dynamic_entity_reference
diff --git a/tests/modules/dynamic_entity_reference_test_views/dynamic_entity_reference_test_views.info.yml b/tests/modules/dynamic_entity_reference_test_views/dynamic_entity_reference_test_views.info.yml
index 702633c815aebff4483140af52528de9b2d489eb..7a8872124909a9c838f6e86741278ced87ec0f96 100644
--- a/tests/modules/dynamic_entity_reference_test_views/dynamic_entity_reference_test_views.info.yml
+++ b/tests/modules/dynamic_entity_reference_test_views/dynamic_entity_reference_test_views.info.yml
@@ -2,8 +2,8 @@ name: 'Dynamic entity reference test views'
 type: module
 description: 'Provides default views for views dynamic entity reference tests.'
 package: Testing
-core_version_requirement: ^9.3 || ^10
-php: 8.0
+core_version_requirement: ^10
+php: 8.1
 hidden: TRUE
 dependencies:
   - dynamic_entity_reference:dynamic_entity_reference