diff --git a/built_value_generator/lib/src/dart_types.dart b/built_value_generator/lib/src/dart_types.dart
index a4f66e48..f485ebe0 100644
--- a/built_value_generator/lib/src/dart_types.dart
+++ b/built_value_generator/lib/src/dart_types.dart
@@ -113,7 +113,7 @@ class DartTypes {
     } else if (dartType is TypeParameterType) {
       return dartType.element.name + suffix;
     } else if (dartType is RecordType) {
-      return dartType.getDisplayString(withNullability: false);
+      return dartType.getDisplayString();
     } else if (dartType is VoidType) {
       return 'void';
     } else if (dartType.isBottom) {
diff --git a/built_value_generator/lib/src/enum_source_class.dart b/built_value_generator/lib/src/enum_source_class.dart
index ab37f41c..beb377fe 100644
--- a/built_value_generator/lib/src/enum_source_class.dart
+++ b/built_value_generator/lib/src/enum_source_class.dart
@@ -12,8 +12,7 @@ import 'package:built_value_generator/src/dart_types.dart';
 import 'package:built_value_generator/src/enum_source_field.dart';
 import 'package:built_value_generator/src/parsed_library_results.dart';
 import 'package:built_value_generator/src/strings.dart';
-import 'package:collection/collection.dart'
-    show IterableExtension, IterableNullableExtension;
+import 'package:collection/collection.dart' show IterableExtension;
 
 import 'library_elements.dart';
 
@@ -114,7 +113,7 @@ abstract class EnumSourceClass
       valuesIdentifier,
       valueOfIdentifier,
       for (var field in fields) field.generatedIdentifier,
-    ].whereNotNull().toList();
+    ].nonNulls.toList();
   }
 
   static bool needsEnumClass(ClassElement classElement) {
diff --git a/built_value_generator/lib/src/fields.dart b/built_value_generator/lib/src/fields.dart
index 0129fd19..2d86565f 100644
--- a/built_value_generator/lib/src/fields.dart
+++ b/built_value_generator/lib/src/fields.dart
@@ -57,7 +57,7 @@ BuiltList<FieldElement> _fieldElementsForType(InterfaceType type) {
   var result = ListBuilder<FieldElement>();
   for (var accessor in type.accessors) {
     if (accessor.isSetter) continue;
-    result.add(accessor.variable as FieldElement);
+    result.add(accessor.variable2 as FieldElement);
   }
   return result.build();
 }
diff --git a/built_value_generator/lib/src/serializer_source_library.dart b/built_value_generator/lib/src/serializer_source_library.dart
index e74f88a2..484b0831 100644
--- a/built_value_generator/lib/src/serializer_source_library.dart
+++ b/built_value_generator/lib/src/serializer_source_library.dart
@@ -47,7 +47,7 @@ abstract class SerializerSourceLibrary
         .toList();
 
     for (var accessor in accessors) {
-      final annotations = accessor.variable.metadata
+      final annotations = accessor.variable2!.metadata
           .where((annotation) =>
               DartTypes.tryGetName(annotation.computeConstantValue()?.type) ==
               'SerializersFor')
@@ -72,7 +72,7 @@ abstract class SerializerSourceLibrary
         .toList();
 
     for (var accessor in accessors) {
-      final annotations = accessor.variable.metadata
+      final annotations = accessor.variable2!.metadata
           .where((annotation) =>
               DartTypes.tryGetName(annotation.computeConstantValue()?.type) ==
               'SerializersFor')
diff --git a/built_value_generator/lib/src/value_source_class.dart b/built_value_generator/lib/src/value_source_class.dart
index 12f9a0b5..eaa3fc96 100644
--- a/built_value_generator/lib/src/value_source_class.dart
+++ b/built_value_generator/lib/src/value_source_class.dart
@@ -364,7 +364,7 @@ abstract class ValueSourceClass
     // Check for any `toString` implementation apart from the one defined on
     // `Object`.
     var method = element.lookUpConcreteMethod('toString', element.library)!;
-    var clazz = method.enclosingElement;
+    var clazz = method.enclosingElement3;
     return clazz is! ClassElement || clazz.name != 'Object';
   }
 
diff --git a/built_value_generator/pubspec.yaml b/built_value_generator/pubspec.yaml
index 6728835b..2f1173f4 100644
--- a/built_value_generator/pubspec.yaml
+++ b/built_value_generator/pubspec.yaml
@@ -10,10 +10,10 @@ topics:
  - build-runner
 
 environment:
-  sdk: '>=3.0.0 <4.0.0'
+  sdk: '>=3.6.0-edge <4.0.0'
 
 dependencies:
-  analyzer: '>=5.2.0 <7.0.0'
+  analyzer: '>=6.9.0 <7.0.0'
   build: '>=1.0.0 <3.0.0'
   build_config: '>=0.3.1 <2.0.0'
   built_collection: ^5.0.0