diff --git a/pkg/nnbd_migration/lib/src/graph_builder.dart b/pkg/nnbd_migration/lib/src/graph_builder.dart
index b673ac5..6ccfb93 100644
--- a/pkg/nnbd_migration/lib/src/graph_builder.dart
+++ b/pkg/nnbd_migration/lib/src/graph_builder.dart
@@ -14,12 +14,10 @@
 import 'package:nnbd_migration/nnbd_migration.dart';
 import 'package:nnbd_migration/src/conditional_discard.dart';
 import 'package:nnbd_migration/src/decorated_type.dart';
+import 'package:nnbd_migration/src/edge_origin.dart';
 import 'package:nnbd_migration/src/expression_checks.dart';
 import 'package:nnbd_migration/src/node_builder.dart';
 import 'package:nnbd_migration/src/nullability_node.dart';
-import 'package:nnbd_migration/src/variables.dart';
-
-import 'edge_origin.dart';
 
 /// Visitor that builds nullability graph edges by examining code to be
 /// migrated.