Hi Sahithi,
thank you for rebasing it. I have applied it successfully and I tested the output with this command: ./pre-inst-env guix build --no-grafts --check hello When I run this in the source directory I do see colours and extra dots on every new line, and I see a couple of missing space characters, just as your code specifies it. Do you see this too? (If not, can you tell us what terminal you are using?) At the very least you should see that every line starts with a dot. The next steps are to fix the errors in the regular expressions that swallow certain space characters and to re-read the documentation of “make-soft-port” to make sure that the procedures in the vector behave as they should. -- Ricardo