diff --git a/composer.json b/composer.json
index 9df33ce..07a0585 100644
--- a/composer.json
+++ b/composer.json
@@ -13,13 +13,12 @@
         }
     ],
     "require": {
-        "php": ">=5.5.0",
+        "php": ">=7.0",
         "menarasolutions/geographer-data": "^0.1.0"
     },
     "require-dev": {
-        "phpunit/phpunit": "4.*|5.*",
-        "codeclimate/php-test-reporter": "dev-master",
-        "illuminate/support": "5.*",
+        "phpunit/phpunit": "^9.0",
+        "illuminate/support": "5.*|6.*|7.*|8.*|9.*",
         "menarasolutions/geographer-da": "0.*",
         "menarasolutions/geographer-de": "0.*",
         "menarasolutions/geographer-ru": "0.*",
diff --git a/src/Traits/ExposesFields.php b/src/Traits/ExposesFields.php
index d4ea60a..2fea093 100644
--- a/src/Traits/ExposesFields.php
+++ b/src/Traits/ExposesFields.php
@@ -13,7 +13,7 @@ trait ExposesFields
      * @param mixed $offset
      * @return boolean
      */
-    public function offsetExists($offset)
+    public function offsetExists($offset): bool
     {
         return isset($this->exposed[$offset]);
     }
diff --git a/tests/Geographer/Integration/CityTest.php b/tests/Geographer/Integration/CityTest.php
index 14e4ab8..985cfd4 100644
--- a/tests/Geographer/Integration/CityTest.php
+++ b/tests/Geographer/Integration/CityTest.php
@@ -6,7 +6,7 @@
 use MenaraSolutions\Geographer\City;
 use MenaraSolutions\Geographer\State;
 
-class CityTest extends \PHPUnit_Framework_TestCase
+class CityTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Countries that don't have any big cities
diff --git a/tests/Geographer/Test.php b/tests/Geographer/Test.php
index 28cadc9..2fbdce4 100644
--- a/tests/Geographer/Test.php
+++ b/tests/Geographer/Test.php
@@ -4,14 +4,14 @@
 
 use MenaraSolutions\Geographer\Earth;
 
-abstract class Test extends \PHPUnit_Framework_TestCase
+abstract class Test extends \PHPUnit\Framework\TestCase
 {
     use AnalyzesPerformance;
 
     /**
      * @return void
      */
-    public function setUp()
+    public function setUp(): void
     {
         $this->performanceHook();
         parent::setUp();
@@ -20,9 +20,9 @@ public function setUp()
     /**
      * @return void
      */
-    public function tearDown()
+    public function tearDown(): void
     {
         $this->performanceCheck();
         parent::tearDown();
     }
-}
\ No newline at end of file
+}