diff --git a/src/core/etl/src/Flow/ETL/Function/ScalarFunctionChain.php b/src/core/etl/src/Flow/ETL/Function/ScalarFunctionChain.php
index 78145b145..df8c7ad0d 100644
--- a/src/core/etl/src/Flow/ETL/Function/ScalarFunctionChain.php
+++ b/src/core/etl/src/Flow/ETL/Function/ScalarFunctionChain.php
@@ -151,9 +151,9 @@ public function greaterThanEqual(ScalarFunction $ref) : self
         return new GreaterThanEqual($this, $ref);
     }
 
-    public function hash(?Algorithm $algorithm = null) : self
+    public function hash(Algorithm $algorithm = new NativePHPHash()) : self
     {
-        return new Hash($this, $algorithm ?? new NativePHPHash());
+        return new Hash($this, $algorithm);
     }
 
     public function isEven() : self
diff --git a/src/core/etl/src/Flow/ETL/Row.php b/src/core/etl/src/Flow/ETL/Row.php
index 5102d7e0a..697f7f542 100644
--- a/src/core/etl/src/Flow/ETL/Row.php
+++ b/src/core/etl/src/Flow/ETL/Row.php
@@ -55,10 +55,8 @@ public function has(string|Reference $ref) : bool
         return $this->entries->has($ref);
     }
 
-    public function hash(?Algorithm $algorithm = null) : string
+    public function hash(Algorithm $algorithm = new NativePHPHash()) : string
     {
-        $algorithm = $algorithm ?? new NativePHPHash();
-
         $string = '';
 
         foreach ($this->entries->sort()->all() as $entry) {
diff --git a/src/core/etl/src/Flow/ETL/Rows.php b/src/core/etl/src/Flow/ETL/Rows.php
index 371c71d48..2fd5de2b6 100644
--- a/src/core/etl/src/Flow/ETL/Rows.php
+++ b/src/core/etl/src/Flow/ETL/Rows.php
@@ -268,10 +268,8 @@ public function getIterator() : \Iterator
         return new \ArrayIterator($this->rows);
     }
 
-    public function hash(?Algorithm $algorithm = null) : string
+    public function hash(Algorithm $algorithm = new NativePHPHash()) : string
     {
-        $algorithm = $algorithm ?? new NativePHPHash();
-
         $hashes = [];
 
         foreach ($this->rows as $row) {