Thanks for any suggestions on fixing hold violations using ECO. can I enable 'export ECO_ENABLE =1' in the red-colored 'makefile' below, before running 'make user_proj_example' command? ECO_ENABLE variable currently is not in this 'makefile', so how to add, I mean, any requirements on the line number I should put it? thank you!

You can enable/disable any configuration variable based on your design requirement by adding into openlane/user_proj_example/config.tcl same applicable to user_project_wrapper/config.tcl