| Name | Lines of code | Maintainability | Test coverage |
| lib/chrono_model/time_machine/history_model.rb | 135 | A 45 mins | A 97% |
| lib/chrono_model/adapter/migrations.rb | 139 | A 1 hr | B 85% |
| lib/chrono_model/time_machine.rb | 146 | A 1 hr | A 96% |
| lib/chrono_model/adapter/ddl.rb | 151 | A 3 hrs | A 96% |