diff --git a/.github/workflows/code-quality.yaml b/.github/workflows/code-quality.yaml
index cabf0a2..233ef1a 100644
--- a/.github/workflows/code-quality.yaml
+++ b/.github/workflows/code-quality.yaml
@@ -23,7 +23,7 @@ jobs:
     name: "Code Quality (PHP${{matrix.php_versions}})"
     strategy:
       matrix:
-        php_versions: ['7.4', '8.0', '8.1', '8.2', '8.3']
+        php_versions: ['8.0', '8.1', '8.2', '8.3', '8.4', '8.5']
       fail-fast: true
     runs-on: ubuntu-latest
     timeout-minutes: 15
@@ -54,5 +54,4 @@ jobs:
         run: ./vendor/bin/phpunit
 
       - name: Mutation Tests
-        if: matrix.php_versions != '7.4'
         run: infection run -c infection.dist.json
diff --git a/composer.json b/composer.json
index 0d2029a..aacdbde 100644
--- a/composer.json
+++ b/composer.json
@@ -14,9 +14,12 @@
   ],
   "config": {
     "platform": {
-      "php": "7.4"
+      "php": "8.0"
     }
   },
+  "require": {
+    "php": ">=8.0"
+  },
   "require-dev": {
     "phpunit/phpunit": "*",
     "vimeo/psalm": "^5.1"
diff --git a/composer.lock b/composer.lock
index 79257bb..e0a8c26 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": "eee0ba07948c8ad3aaffacb67e046a41",
+    "content-hash": "6dedaaddfb6da2e880f85085959ed001",
     "packages": [],
     "packages-dev": [
         {
@@ -3755,13 +3755,15 @@
     ],
     "aliases": [],
     "minimum-stability": "stable",
-    "stability-flags": [],
+    "stability-flags": {},
     "prefer-stable": false,
     "prefer-lowest": false,
-    "platform": [],
-    "platform-dev": [],
+    "platform": {
+        "php": ">=8.0"
+    },
+    "platform-dev": {},
     "platform-overrides": {
-        "php": "7.4"
+        "php": "8.0"
     },
-    "plugin-api-version": "2.3.0"
+    "plugin-api-version": "2.9.0"
 }
diff --git a/src/Number/Integer.php b/src/Number/Integer.php
index aa61608..a6015ed 100644
--- a/src/Number/Integer.php
+++ b/src/Number/Integer.php
@@ -28,7 +28,7 @@ final public function getValue(): int
     final public static function fromNumeric($value): self
     {
         if (is_numeric($value)) {
-            return new self((int)$value);
+            return new static((int)$value);
         }
 
         throw new InvalidArgumentException('Value is not numeric.');
diff --git a/tests/Number/IntegerTest.php b/tests/Number/IntegerTest.php
index cbbbba9..a1e8317 100644
--- a/tests/Number/IntegerTest.php
+++ b/tests/Number/IntegerTest.php
@@ -6,6 +6,7 @@
 
 use Epignosis\Types\Number\Integer;
 use Epignosis\Types\Number\PositiveInteger;
+use InvalidArgumentException;
 use PHPUnit\Framework\TestCase;
 
 final class IntegerTest extends TestCase
@@ -31,6 +32,25 @@ public function test_canBeCreatedFromFloat(): void
         $this->assertEquals(42, $result);
     }
 
+    public function test_canBeCreatedFromNegativeNumericString(): void
+    {
+        $result = Integer::fromNumeric('-42')->getValue();
+
+        $this->assertEquals(-42, $result);
+    }
+
+    public function test_fromNumericReturnsPlainInteger(): void
+    {
+        $this->assertSame(Integer::class, get_class(Integer::fromNumeric('42')));
+    }
+
+    public function test_CannotBeCreatedFromNonNumericString(): void
+    {
+        $this->expectException(InvalidArgumentException::class);
+
+        Integer::fromNumeric('abc');
+    }
+
     public function test_IsEqualToSameTypeWithSameValue(): void
     {
         $integer1 = new Integer(42);
diff --git a/tests/Number/NonNegativeIntegerTest.php b/tests/Number/NonNegativeIntegerTest.php
index 0b022be..3e54e3c 100644
--- a/tests/Number/NonNegativeIntegerTest.php
+++ b/tests/Number/NonNegativeIntegerTest.php
@@ -39,6 +39,32 @@ public function test_canBeCreatedFromFloat(): void
         $this->assertEquals(42, $result);
     }
 
+    public function test_fromNumericReturnsInstanceOfCalledClass(): void
+    {
+        $this->assertInstanceOf(NonNegativeInteger::class, NonNegativeInteger::fromNumeric('42'));
+    }
+
+    public function test_canBeCreatedFromZeroNumericString(): void
+    {
+        $result = NonNegativeInteger::fromNumeric('0')->getValue();
+
+        $this->assertEquals(0, $result);
+    }
+
+    public function test_CannotBeCreatedFromNegativeNumericString(): void
+    {
+        $this->expectException(InvalidArgumentException::class);
+
+        NonNegativeInteger::fromNumeric('-42');
+    }
+
+    public function test_CannotBeCreatedFromNegativeFloat(): void
+    {
+        $this->expectException(InvalidArgumentException::class);
+
+        NonNegativeInteger::fromNumeric(-42.3);
+    }
+
     public function test_CannotBeCreatedFromNegativeInteger(): void
     {
         $this->expectException(InvalidArgumentException::class);
diff --git a/tests/Number/PositiveIntegerTest.php b/tests/Number/PositiveIntegerTest.php
index 0c4bdb4..ec657e5 100644
--- a/tests/Number/PositiveIntegerTest.php
+++ b/tests/Number/PositiveIntegerTest.php
@@ -73,4 +73,30 @@ public function test_isNotEqualToDifferentType(): void
         $this->assertFalse($integer1->equals($integer2));
         $this->assertFalse($integer2->equals($integer1));
     }
+
+    public function test_fromNumericReturnsInstanceOfCalledClass(): void
+    {
+        $this->assertInstanceOf(PositiveInteger::class, PositiveInteger::fromNumeric('42'));
+    }
+
+    public function test_CannotBeCreatedFromNegativeNumericString(): void
+    {
+        $this->expectException(InvalidArgumentException::class);
+
+        PositiveInteger::fromNumeric('-42');
+    }
+
+    public function test_CannotBeCreatedFromZeroNumericString(): void
+    {
+        $this->expectException(InvalidArgumentException::class);
+
+        PositiveInteger::fromNumeric('0');
+    }
+
+    public function test_CannotBeCreatedFromNegativeFloat(): void
+    {
+        $this->expectException(InvalidArgumentException::class);
+
+        PositiveInteger::fromNumeric(-42.3);
+    }
 }