Store file names / how to intern files in subdirectory?

[Nils Landt <nils@landt.email>]

Hello,

I'm working on my home-systemd-service, and systemd cares about the file name behind links. Specifically, it emits a warning when the file name of the link target does not match the link name.
Example:
ls -alh ~/.config/systemd/user/default.target.wants/greenclip.service ->
/home/nl/.config/systemd/user/default.target.wants/greenclip.service -> /gnu/store/pznbc8xxhfkwxjbaff9h982cy4df1y1a-greenclip.service

results in this log message:
"default.target: Wants dependency dropin /home/nl/.config/systemd/user/default.target.wants/greenclip.service target /gnu/store/pznbc8xxhfkwxjbaff9h982cy4df1y1a-greenclip.service has different name".

Still, I would like to fix this warning.
The file is a serialized configuration created with (mixed-text-file "greenclip.service" (serialize-configuration ...)).
If I change the first argument to "test/greenclip.service", I get an error, so it's really just the file name, not a path.
I understand it makes no sense to try to get /gnu/store/greenclip.service, but would it be possible to achieve /gnu/store/pznbc8xxhfkwxjbaff9h982cy4df1y1a-greenclip.service/some-directory/greenclip.service? Or are files always saved at the "top level" of the store?

Nils