Thanks for your explanations. It's cleared up my understanding. I've tried to retitled to target core-updates, but I'm not sure if it applied. I've updated the patch to include a unit test. I am currently testing by rebuilding as you suggest. ./pre-inst-env guix build hello Yes this is building the world so I will report back when it completes. >The record is . != elf-dynamic-info. Thank you. Yes I was confused regarding this. I've updated the commit changelog accordingly.