diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 9f3ceee..296194d 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -7,7 +7,7 @@ jobs:
         runs-on: ubuntu-latest
         strategy:
             matrix:
-                php: ['8.0', '8.1', '8.2', '8.3']
+                php: ['8.0', '8.1', '8.2', '8.3', '8.4']
 
             fail-fast: false
 
diff --git a/composer.json b/composer.json
index df8ad21..d2971d2 100644
--- a/composer.json
+++ b/composer.json
@@ -15,7 +15,7 @@
 		}
 	],
 	"require": {
-		"php": "8.0 - 8.3",
+		"php": "8.0 - 8.4",
 		"ext-json": "*"
 	},
 	"require-dev": {
diff --git a/readme.md b/readme.md
index ab46729..491b70d 100644
--- a/readme.md
+++ b/readme.md
@@ -39,7 +39,7 @@ Install via Composer:
 composer require nette/neon
 ```
 
-It requires PHP version 8.0 up to 8.3. Documentation can be found on the [website](https://doc.nette.org/neon).
+It requires PHP version 8.0 up to 8.4. Documentation can be found on the [website](https://doc.nette.org/neon).
 
 `Neon::encode()` returns `$value` converted to NEON. As the second parameter `$blockMode` you can pass true, which will create multiline output. The third parameter `$indentation` specifies the characters used for indentation (default is tab).
 
diff --git a/src/Neon/Parser.php b/src/Neon/Parser.php
index f53eca1..a2a4a1c 100644
--- a/src/Neon/Parser.php
+++ b/src/Neon/Parser.php
@@ -240,7 +240,7 @@ private function checkArrayKey(Node $key, array &$arr): void
 	}
 
 
-	private function injectPos(Node $node, int $start = null, int $end = null): Node
+	private function injectPos(Node $node, ?int $start = null, ?int $end = null): Node
 	{
 		$node->startTokenPos = $start ?? $this->tokens->getPos();
 		$node->startLine = $this->posToLine[$node->startTokenPos];