diff --git a/apps/flutter_client_contract_test_service/bin/contract_test_service.dart b/apps/flutter_client_contract_test_service/bin/contract_test_service.dart
index 6024cb7..0d54be1 100644
--- a/apps/flutter_client_contract_test_service/bin/contract_test_service.dart
+++ b/apps/flutter_client_contract_test_service/bin/contract_test_service.dart
@@ -23,7 +23,7 @@ class TestApiImpl extends SdkTestApi {
     'tags',
     'client-independence',
     'context-comparison',
-    'inline-context',
+    'inline-context-all',
     'anonymous-redaction',
     'client-prereq-events',
     'auto-env-attributes',
diff --git a/packages/common/lib/src/events/default_event_processor.dart b/packages/common/lib/src/events/default_event_processor.dart
index e68e496..bcbbc40 100644
--- a/packages/common/lib/src/events/default_event_processor.dart
+++ b/packages/common/lib/src/events/default_event_processor.dart
@@ -95,7 +95,9 @@ final class DefaultEventProcessor implements EventProcessor {
 
   @override
   void processCustomEvent(CustomEvent event) {
-    _enqueue(CustomEventSerialization.toJson(event));
+    _enqueue(CustomEventSerialization.toJson(event,
+        allAttributesPrivate: _allAttributesPrivate,
+        globalPrivateAttributes: _globalPrivateAttributes));
   }
 
   @override
diff --git a/packages/common/lib/src/serialization/event_serialization.dart b/packages/common/lib/src/serialization/event_serialization.dart
index 0c5c58f..644c53c 100644
--- a/packages/common/lib/src/serialization/event_serialization.dart
+++ b/packages/common/lib/src/serialization/event_serialization.dart
@@ -18,7 +18,9 @@ final class IdentifyEventSerialization {
 }
 
 final class CustomEventSerialization {
-  static Map<String, dynamic> toJson(CustomEvent event) {
+  static Map<String, dynamic> toJson(CustomEvent event,
+      {required bool allAttributesPrivate,
+      required Set<AttributeReference> globalPrivateAttributes}) {
     final json = <String, dynamic>{};
 
     json['kind'] = 'custom';
@@ -30,7 +32,10 @@ final class CustomEventSerialization {
     if (event.metricValue != null) {
       json['metricValue'] = event.metricValue;
     }
-    json['contextKeys'] = event.context.keys;
+    json['context'] = LDContextSerialization.toJson(event.context,
+        isEvent: true,
+        allAttributesPrivate: allAttributesPrivate,
+        globalPrivateAttributes: globalPrivateAttributes);
 
     return json;
   }
diff --git a/packages/common/test/serialization/event_serialization_test.dart b/packages/common/test/serialization/event_serialization_test.dart
index a88999b..0725bd9 100644
--- a/packages/common/test/serialization/event_serialization_test.dart
+++ b/packages/common/test/serialization/event_serialization_test.dart
@@ -88,7 +88,8 @@ void main() {
         context: LDContextBuilder().kind('user', 'user-key').build(),
         key: 'my-key');
 
-    final json = jsonEncode(CustomEventSerialization.toJson(event));
+    final json = jsonEncode(CustomEventSerialization.toJson(event,
+        allAttributesPrivate: false, globalPrivateAttributes: {}));
 
     final jsonAsLdValue = LDValueSerialization.fromJson(jsonDecode(json));
 
@@ -96,8 +97,9 @@ void main() {
         '"kind": "custom",'
         '"key": "my-key",'
         '"creationDate": 0,'
-        '"contextKeys": {'
-        '"user": "user-key"'
+        '"context": {'
+        '"kind": "user",'
+        '"key": "user-key"'
         '}'
         '}'));
 
@@ -111,7 +113,8 @@ void main() {
         context: LDContextBuilder().kind('user', 'user-key').build(),
         key: 'my-key');
 
-    final json = jsonEncode(CustomEventSerialization.toJson(event));
+    final json = jsonEncode(CustomEventSerialization.toJson(event,
+        allAttributesPrivate: false, globalPrivateAttributes: {}));
 
     final jsonAsLdValue = LDValueSerialization.fromJson(jsonDecode(json));
 
@@ -120,8 +123,9 @@ void main() {
         '"metricValue": 100,'
         '"key": "my-key",'
         '"creationDate": 0,'
-        '"contextKeys": {'
-        '"user": "user-key"'
+        '"context": {'
+        '"kind": "user",'
+        '"key": "user-key"'
         '}'
         '}'));
 
@@ -135,7 +139,8 @@ void main() {
         context: LDContextBuilder().kind('user', 'user-key').build(),
         key: 'my-key');
 
-    final json = jsonEncode(CustomEventSerialization.toJson(event));
+    final json = jsonEncode(CustomEventSerialization.toJson(event,
+        allAttributesPrivate: false, globalPrivateAttributes: {}));
 
     final jsonAsLdValue = LDValueSerialization.fromJson(jsonDecode(json));
 
@@ -144,8 +149,9 @@ void main() {
         '"key": "my-key",'
         '"data": {"test": "value"},'
         '"creationDate": 0,'
-        '"contextKeys": {'
-        '"user": "user-key"'
+        '"context": {'
+        '"kind": "user",'
+        '"key": "user-key"'
         '}'
         '}'));
 
@@ -160,7 +166,8 @@ void main() {
         context: LDContextBuilder().kind('user', 'user-key').build(),
         key: 'my-key');
 
-    final json = jsonEncode(CustomEventSerialization.toJson(event));
+    final json = jsonEncode(CustomEventSerialization.toJson(event,
+        allAttributesPrivate: false, globalPrivateAttributes: {}));
 
     final jsonAsLdValue = LDValueSerialization.fromJson(jsonDecode(json));
 
@@ -170,8 +177,9 @@ void main() {
         '"data": {"test": "value"},'
         '"metricValue": 100,'
         '"creationDate": 0,'
-        '"contextKeys": {'
-        '"user": "user-key"'
+        '"context": {'
+        '"kind": "user",'
+        '"key": "user-key"'
         '}'
         '}'));