diff --git a/proto/shared/shared.flow_definition.proto b/proto/shared/shared.flow_definition.proto
index 4373dc3..efced69 100644
--- a/proto/shared/shared.flow_definition.proto
+++ b/proto/shared/shared.flow_definition.proto
@@ -5,26 +5,24 @@ option ruby_package = "Tucana::Shared";
 package shared;
 
 import "shared.translation.proto";
-import "shared.data_type.proto";
 import "shared.struct.proto";
 import "shared.flow.proto";
 
 message FlowType {
-  FlowDefinition definition = 1;
-  repeated shared.Translation name = 2;
+  string identifier = 1;
+  repeated FlowTypeSetting settings = 2;
+  optional string input_type_identifier = 3;
+  optional string return_type_identifier = 4;
+  bool editable = 5;
+  repeated shared.Translation name = 6;
+  repeated shared.Translation description = 7;
 }
 
-message FlowDefinitionSetting {
-  bool unique = 1;
-  shared.DataType type = 2;
-  optional shared.Struct default_value = 3;
-  repeated shared.Translation name = 4;
-  repeated shared.Translation description = 5;
-}
-
-message FlowDefinition {
-  repeated FlowDefinitionSetting settings = 1;
-  shared.DataType input_type = 2;
-  optional shared.DataType return_type = 3;
-  bool editable = 4;
+message FlowTypeSetting {
+  string identifier = 1;
+  bool unique = 2;
+  string data_type_identifier = 3;
+  optional shared.Value default_value = 4;
+  repeated shared.Translation name = 5;
+  repeated shared.Translation description = 6;
 }