diff --git a/src/world/format/io/FastChunkSerializer.php b/src/world/format/io/FastChunkSerializer.php
index d2ff75755..e41776d32 100644
--- a/src/world/format/io/FastChunkSerializer.php
+++ b/src/world/format/io/FastChunkSerializer.php
@@ -41,6 +41,9 @@ use function unpack;
  * The serialization format **is not intended for permanent storage** and may change without warning.
  */
 final class FastChunkSerializer{
+	private const FLAG_GENERATED = 1 << 0;
+	private const FLAG_POPULATED = 1 << 1;
+	private const FLAG_HAS_LIGHT = 1 << 2;
 
 	private function __construct(){
 		//NOOP
@@ -60,7 +63,11 @@ final class FastChunkSerializer{
 		$stream = new BinaryStream();
 		$stream->putInt($chunk->getX());
 		$stream->putInt($chunk->getZ());
-		$stream->putByte(($includeLight ? 4 : 0) | ($chunk->isPopulated() ? 2 : 0) | ($chunk->isGenerated() ? 1 : 0));
+		$stream->putByte(
+			($includeLight ? self::FLAG_HAS_LIGHT : 0) |
+			($chunk->isPopulated() ? self::FLAG_POPULATED : 0) |
+			($chunk->isGenerated() ? self::FLAG_GENERATED : 0)
+		);
 		if($chunk->isGenerated()){
 			//subchunks
 			$subChunks = $chunk->getSubChunks();
@@ -107,9 +114,9 @@ final class FastChunkSerializer{
 		$x = $stream->getInt();
 		$z = $stream->getInt();
 		$flags = $stream->getByte();
-		$lightPopulated = (bool) ($flags & 4);
-		$terrainPopulated = (bool) ($flags & 2);
-		$terrainGenerated = (bool) ($flags & 1);
+		$lightPopulated = (bool) ($flags & self::FLAG_HAS_LIGHT);
+		$terrainPopulated = (bool) ($flags & self::FLAG_POPULATED);
+		$terrainGenerated = (bool) ($flags & self::FLAG_GENERATED);
 
 		$subChunks = [];
 		$biomeIds = null;