diff --git a/modules/puppet_proxy_puppet_api/plugin_configuration.rb b/modules/puppet_proxy_puppet_api/plugin_configuration.rb
index e3a8067fc..9f6e6eb54 100644
--- a/modules/puppet_proxy_puppet_api/plugin_configuration.rb
+++ b/modules/puppet_proxy_puppet_api/plugin_configuration.rb
@@ -14,6 +14,7 @@ def load_classes
       require 'puppet_proxy_common/api_request'
       require 'puppet_proxy_puppet_api/v3_api_request'
       require 'puppet_proxy_puppet_api/v3_environments_retriever'
+      require 'puppet_proxy_puppet_api/v3_environment_classes_api_classes_retriever'
     end
 
     def load_dependency_injection_wirings(container_instance, settings)