diff --git a/lib/nbt/NbtIo.dart b/lib/nbt/NbtIo.dart
index 5d64f6b..f7ffcdd 100644
--- a/lib/nbt/NbtIo.dart
+++ b/lib/nbt/NbtIo.dart
@@ -33,11 +33,15 @@ class NbtIo {
     return Tag.readNamedTag(_io) as CompoundTag;
   }
 
-  static Future<void> write(String file) async {
+  static Future<void> write(String file, CompoundTag tag) async {
+    _io = ByteLayer();
+    Tag.writeNamedTag(tag, _io);
     await _io.writeToFile(file);
   }
 
-  static Future<void> writeCompressed(String file) async {
+  static Future<void> writeCompressed(String file, CompoundTag tag) async {
+    _io = ByteLayer();
+    Tag.writeNamedTag(tag, _io);
     await _io.compress();
     await _io.writeToFile(file);
   }