diff --git a/modules/Collection/src/ArraySet.php b/modules/Collection/src/ArraySet.php
index 33918779..a531d5fa 100644
--- a/modules/Collection/src/ArraySet.php
+++ b/modules/Collection/src/ArraySet.php
@@ -7,8 +7,6 @@
 use Closure;
 use Elephox\Collection\Contract\GenericSet;
 use Iterator;
-use IteratorIterator;
-use Traversable;
 
 /**
  * @template T
diff --git a/modules/Collection/src/IsKeyedEnumerable.php b/modules/Collection/src/IsKeyedEnumerable.php
index ce476487..e7272abc 100644
--- a/modules/Collection/src/IsKeyedEnumerable.php
+++ b/modules/Collection/src/IsKeyedEnumerable.php
@@ -34,6 +34,7 @@
 use RecursiveIteratorIterator;
 use Stringable;
 use Traversable;
+
 use const JSON_FORCE_OBJECT;
 use const JSON_HEX_AMP;
 use const JSON_HEX_APOS;
diff --git a/modules/Collection/test/ArrayListTest.php b/modules/Collection/test/ArrayListTest.php
index 65f3aa78..a54df643 100644
--- a/modules/Collection/test/ArrayListTest.php
+++ b/modules/Collection/test/ArrayListTest.php
@@ -36,7 +36,7 @@ public function testCount(): void
 		$arr = new ArrayList(['test', 'test2', 'test3']);
 
 		self::assertCount(3, $arr);
-		self::assertSame(2, $arr->count(fn ($v) => strlen($v) === 5));
+		self::assertSame(2, $arr->count(static fn ($v) => strlen($v) === 5));
 	}
 
 	public function testOffsetUnset(): void
diff --git a/modules/Collection/test/ArraySetTest.php b/modules/Collection/test/ArraySetTest.php
index c6386b70..5de146bd 100644
--- a/modules/Collection/test/ArraySetTest.php
+++ b/modules/Collection/test/ArraySetTest.php
@@ -84,6 +84,6 @@ public function testCount(): void
 
 		self::assertCount(3, $set);
 		self::assertSame(3, $set->count());
-		self::assertSame(1, $set->count(fn ($v) => $v === 'b'));
+		self::assertSame(1, $set->count(static fn ($v) => $v === 'b'));
 	}
 }
diff --git a/modules/Collection/test/FlipIteratorTest.php b/modules/Collection/test/FlipIteratorTest.php
index 54d01c10..3dc29445 100644
--- a/modules/Collection/test/FlipIteratorTest.php
+++ b/modules/Collection/test/FlipIteratorTest.php
@@ -19,6 +19,6 @@ public function testGetInnerIterator(): void
 		$it = new ArrayIterator([]);
 		$flip = new FlipIterator($it);
 
-		$this->assertSame($it, $flip->getInnerIterator());
+		self::assertSame($it, $flip->getInnerIterator());
 	}
 }
diff --git a/modules/Collection/test/KeySelectIteratorTest.php b/modules/Collection/test/KeySelectIteratorTest.php
index da2421cc..c58a6b6c 100644
--- a/modules/Collection/test/KeySelectIteratorTest.php
+++ b/modules/Collection/test/KeySelectIteratorTest.php
@@ -17,8 +17,8 @@ final class KeySelectIteratorTest extends TestCase
 	public function testGetInnerIterator(): void
 	{
 		$it = new ArrayIterator([]);
-		$keySelect = new KeySelectIterator($it, fn ($v) => $v);
+		$keySelect = new KeySelectIterator($it, static fn ($v) => $v);
 
-		$this->assertSame($it, $keySelect->getInnerIterator());
+		self::assertSame($it, $keySelect->getInnerIterator());
 	}
 }
diff --git a/modules/Collection/test/SelectIteratorTest.php b/modules/Collection/test/SelectIteratorTest.php
index 3f2132e3..ad98cfa8 100644
--- a/modules/Collection/test/SelectIteratorTest.php
+++ b/modules/Collection/test/SelectIteratorTest.php
@@ -17,8 +17,8 @@ final class SelectIteratorTest extends TestCase
 	public function testGetInnerIterator(): void
 	{
 		$it = new ArrayIterator([]);
-		$select = new SelectIterator($it, fn ($v) => $v);
+		$select = new SelectIterator($it, static fn ($v) => $v);
 
-		$this->assertSame($it, $select->getInnerIterator());
+		self::assertSame($it, $select->getInnerIterator());
 	}
 }
diff --git a/modules/Collection/test/UniqueByIteratorTest.php b/modules/Collection/test/UniqueByIteratorTest.php
index c5711f2f..c168e2c2 100644
--- a/modules/Collection/test/UniqueByIteratorTest.php
+++ b/modules/Collection/test/UniqueByIteratorTest.php
@@ -25,8 +25,8 @@ public function testIterator(): void
 	public function testGetInnerIterator(): void
 	{
 		$it = new ArrayIterator([]);
-		$select = new UniqueByIterator($it, fn ($v) => $v, DefaultEqualityComparer::same(...));
+		$select = new UniqueByIterator($it, static fn ($v) => $v, DefaultEqualityComparer::same(...));
 
-		$this->assertSame($it, $select->getInnerIterator());
+		self::assertSame($it, $select->getInnerIterator());
 	}
 }