diff --git a/src/core/etl/README.md b/src/core/etl/README.md
index 9c3782e7f..2bb6deff6 100644
--- a/src/core/etl/README.md
+++ b/src/core/etl/README.md
@@ -216,7 +216,6 @@ Adapters might also define some custom transformers.
     * [keep entries](src/Flow/ETL/Transformer/KeepEntriesTransformer.php) - [tests](tests/Flow/ETL/Tests/Unit/Transformer/KeepEntriesTransformerTest.php)
     * [remove entries](src/Flow/ETL/Transformer/RemoveEntriesTransformer.php) - [tests](tests/Flow/ETL/Tests/Unit/Transformer/RemoveEntriesTransformerTest.php)
     * [rename entries](src/Flow/ETL/Transformer/RenameEntryTransformer.php) - [tests](tests/Flow/ETL/Tests/Unit/Transformer/RenameEntryTransformerTest.php)
-    * [static entry](src/Flow/ETL/Transformer/StaticEntryTransformer.php) - [tests](tests/Flow/ETL/Tests/Unit/Transformer/StaticEntryTransformerTest.php)
 * **Array**
     * [array keys style converter](src/Flow/ETL/Transformer/ArrayKeysStyleConverterTransformer.php) - [tests](tests/Flow/ETL/Tests/Unit/Transformer/ArrayKeysStyleConverterTransformerTest.php)
 * **Callback** - *Might come with performance degradation*
diff --git a/src/core/etl/src/Flow/ETL/DSL/Transform.php b/src/core/etl/src/Flow/ETL/DSL/Transform.php
index 38242abd7..76d3f94d5 100644
--- a/src/core/etl/src/Flow/ETL/DSL/Transform.php
+++ b/src/core/etl/src/Flow/ETL/DSL/Transform.php
@@ -4,7 +4,6 @@
 
 namespace Flow\ETL\DSL;
 
-use Flow\ETL\DSL\Entry as DSLEntry;
 use Flow\ETL\Exception\InvalidArgumentException;
 use Flow\ETL\Exception\RuntimeException;
 use Flow\ETL\Row;
@@ -23,27 +22,6 @@
  */
 class Transform
 {
-    /**
-     * @param array<mixed> $data
-     */
-    final public static function add_json(string $name, array $data) : Transformer
-    {
-        return new Transformer\StaticEntryTransformer(DSLEntry::json($name, $data));
-    }
-
-    final public static function add_json_from_string(string $name, string $json) : Transformer
-    {
-        return new Transformer\StaticEntryTransformer(DSLEntry::json($name, (array) \json_decode($json, true, 512, JSON_THROW_ON_ERROR)));
-    }
-
-    /**
-     * @param array<mixed> $data
-     */
-    final public static function add_json_object(string $name, array $data) : Transformer
-    {
-        return new Transformer\StaticEntryTransformer(DSLEntry::json_object($name, $data));
-    }
-
     /**
      * @param ?Schema $schema Desired schema of unpacked elements. Elements not found in schema will be auto detected.
      *                        It is allowed to provide definitions only for selected elements, like for example
diff --git a/src/core/etl/src/Flow/ETL/Transformer/StaticEntryTransformer.php b/src/core/etl/src/Flow/ETL/Transformer/StaticEntryTransformer.php
deleted file mode 100644
index ae3307f0b..000000000
--- a/src/core/etl/src/Flow/ETL/Transformer/StaticEntryTransformer.php
+++ /dev/null
@@ -1,40 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Flow\ETL\Transformer;
-
-use Flow\ETL\FlowContext;
-use Flow\ETL\Row;
-use Flow\ETL\Row\Entry;
-use Flow\ETL\Rows;
-use Flow\ETL\Transformer;
-
-/**
- * @implements Transformer<array{entry: Entry}>
- */
-final class StaticEntryTransformer implements Transformer
-{
-    public function __construct(private readonly Entry $entry)
-    {
-    }
-
-    public function __serialize() : array
-    {
-        return [
-            'entry' => $this->entry,
-        ];
-    }
-
-    public function __unserialize(array $data) : void
-    {
-        $this->entry = $data['entry'];
-    }
-
-    public function transform(Rows $rows, FlowContext $context) : Rows
-    {
-        $transformer = fn (Row $row) : Row => $row->set($this->entry);
-
-        return $rows->map($transformer);
-    }
-}
diff --git a/src/core/etl/tests/Flow/ETL/Tests/Integration/Row/Reference/Expression/AddJsonTest.php b/src/core/etl/tests/Flow/ETL/Tests/Integration/Row/Reference/Expression/AddJsonTest.php
new file mode 100644
index 000000000..964c98713
--- /dev/null
+++ b/src/core/etl/tests/Flow/ETL/Tests/Integration/Row/Reference/Expression/AddJsonTest.php
@@ -0,0 +1,114 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Flow\ETL\Tests\Integration\Row\Reference\Expression;
+
+use function Flow\ETL\DSL\array_unpack;
+use function Flow\ETL\DSL\lit;
+use function Flow\ETL\DSL\ref;
+use Flow\ETL\DSL\From;
+use Flow\ETL\DSL\To;
+use Flow\ETL\Flow;
+use Flow\ETL\Memory\ArrayMemory;
+use PHPUnit\Framework\TestCase;
+
+final class AddJsonTest extends TestCase
+{
+    public function test_add_json_into_existing_reference() : void
+    {
+        (new Flow())
+            ->read(
+                From::array(
+                    [['id' => 1, 'array' => ['a' => 1, 'b' => 2, 'c' => 3]]],
+                )
+            )
+            ->withEntry('row', array_unpack(ref('row')))
+            ->renameAll('row.', '')
+            ->drop('row')
+            ->withEntry('array', ref('array')->arrayMerge(lit(['d' => 4])))
+            ->write(To::memory($memory = new ArrayMemory()))
+            ->run();
+
+        $this->assertSame(
+            [
+                ['id' => 1, 'array' => ['a' => 1, 'b' => 2, 'c' => 3, 'd' => 4]],
+            ],
+            $memory->data
+        );
+    }
+
+    public function test_add_json_string_into_existing_reference() : void
+    {
+        (new Flow())
+            ->read(
+                From::array(
+                    [['id' => 1, 'array' => ['a' => 1, 'b' => 2, 'c' => 3]]],
+                )
+            )
+            ->withEntry('row', array_unpack(ref('row')))
+            ->renameAll('row.', '')
+            ->drop('row')
+            ->withEntry('json', lit('{"d": 4}'))
+            ->withEntry('array', ref('array')->arrayMerge(ref('json')->jsonDecode()))
+            ->drop('json')
+            ->write(To::memory($memory = new ArrayMemory()))
+            ->run();
+
+        $this->assertSame(
+            [
+                ['id' => 1, 'array' => ['a' => 1, 'b' => 2, 'c' => 3, 'd' => 4]],
+            ],
+            $memory->data
+        );
+    }
+
+    public function test_adding_json_as_object_from_string_entry() : void
+    {
+        (new Flow())
+            ->read(
+                From::array([['id' => 1]])
+            )
+            ->withEntry('row', array_unpack(ref('row')))
+            ->renameAll('row.', '')
+            ->drop('row')
+            ->withEntry('json', lit(['id' => 1, 'name' => 'test']))
+            ->withEntry('json', ref('json')->jsonEncode(\JSON_FORCE_OBJECT))
+            ->write(To::memory($memory = new ArrayMemory()))
+            ->run();
+
+        $this->assertSame(
+            [
+                [
+                    'id' => 1,
+                    'json' => '{"id":1,"name":"test"}',
+                ],
+            ],
+            $memory->data
+        );
+    }
+
+    public function test_adding_json_from_string_entry() : void
+    {
+        (new Flow())
+            ->read(
+                From::array([['id' => 1]])
+            )
+            ->withEntry('row', array_unpack(ref('row')))
+            ->renameAll('row.', '')
+            ->drop('row')
+            ->withEntry('json', lit('[{"id":1},{"id":2}]'))
+            ->write(To::memory($memory = new ArrayMemory()))
+            ->run();
+
+        $this->assertSame(
+            [
+                [
+                    'id' => 1,
+                    'json' => '[{"id":1},{"id":2}]',
+                ],
+            ],
+            $memory->data
+        );
+    }
+}
diff --git a/src/core/etl/tests/Flow/ETL/Tests/Unit/Transformer/StaticEntryTransformerTest.php b/src/core/etl/tests/Flow/ETL/Tests/Unit/Transformer/StaticEntryTransformerTest.php
deleted file mode 100644
index 651a8b357..000000000
--- a/src/core/etl/tests/Flow/ETL/Tests/Unit/Transformer/StaticEntryTransformerTest.php
+++ /dev/null
@@ -1,78 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Flow\ETL\Tests\Unit\Transformer;
-
-use Flow\ETL\Config;
-use Flow\ETL\DSL\Transform;
-use Flow\ETL\FlowContext;
-use Flow\ETL\Row;
-use Flow\ETL\Rows;
-use PHPUnit\Framework\TestCase;
-
-final class StaticEntryTransformerTest extends TestCase
-{
-    public function test_adding_json_entry() : void
-    {
-        $transformer = Transform::add_json('json', [['id' => 1], ['id' => 2]]);
-
-        $rows = $transformer->transform(new Rows(
-            Row::create(
-                new Row\Entry\StringEntry('id', '1'),
-            )
-        ), new FlowContext(Config::default()));
-
-        $this->assertEquals(
-            [
-                [
-                    'id' => '1',
-                    'json' => '[{"id":1},{"id":2}]',
-                ],
-            ],
-            $rows->toArray()
-        );
-    }
-
-    public function test_adding_json_from_string_entry() : void
-    {
-        $transformer = Transform::add_json_from_string('json', '[{"id":1},{"id":2}]');
-
-        $rows = $transformer->transform(new Rows(
-            Row::create(
-                new Row\Entry\StringEntry('id', '1'),
-            )
-        ), new FlowContext(Config::default()));
-
-        $this->assertEquals(
-            [
-                [
-                    'id' => '1',
-                    'json' => '[{"id":1},{"id":2}]',
-                ],
-            ],
-            $rows->toArray()
-        );
-    }
-
-    public function test_adding_json_object() : void
-    {
-        $transformer = Transform::add_json_object('json', ['id' => 1, 'name' => 'test']);
-
-        $rows = $transformer->transform(new Rows(
-            Row::create(
-                new Row\Entry\StringEntry('id', '1'),
-            )
-        ), new FlowContext(Config::default()));
-
-        $this->assertEquals(
-            [
-                [
-                    'id' => '1',
-                    'json' => '{"id":1,"name":"test"}',
-                ],
-            ],
-            $rows->toArray()
-        );
-    }
-}