diff --git a/lib/datadog/kit/identity.rb b/lib/datadog/kit/identity.rb
index b2bd8115e50..8f9ccdafe20 100644
--- a/lib/datadog/kit/identity.rb
+++ b/lib/datadog/kit/identity.rb
@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+require_relative '../appsec/instrumentation/gateway/argument'
+
 module Datadog
   module Kit
     # Tracking identity via traces
@@ -57,7 +59,7 @@ def self.set_user(trace, id:, email: nil, name: nil, session_id: nil, role: nil,
         end
 
         if Datadog.configuration.appsec.enabled
-          user = OpenStruct.new(id: id)
+          user = ::Datadog::AppSec::Instrumentation::Gateway::User.new(id)
           ::Datadog::AppSec::Instrumentation.gateway.push('identity.set_user', user)
         end
       end
diff --git a/spec/datadog/kit/identity_spec.rb b/spec/datadog/kit/identity_spec.rb
index b270f7c2755..eef36e492c3 100644
--- a/spec/datadog/kit/identity_spec.rb
+++ b/spec/datadog/kit/identity_spec.rb
@@ -235,10 +235,9 @@
       context 'when is enabled' do
         it 'instruments the user information to appsec' do
           Datadog.configuration.appsec.enabled = true
-          user = OpenStruct.new(id: '42')
           expect_any_instance_of(Datadog::AppSec::Instrumentation::Gateway).to receive(:push).with(
             'identity.set_user',
-            user
+            instance_of(Datadog::AppSec::Instrumentation::Gateway::User)
           )
           described_class.set_user(trace_op, id: '42')
         end