Use a variable Scheme module

[Urs Liska]

Is there a way (well, I think I should ask: what's the way) to use 
Scheme modules whose names are only available at runtime?

(use-modules (root-level my-module))

where my-module might change. What I actually want to achieve is load 
all modules for which .scm files are found in a directory.

Alternatively is there a way to load all submodules of a given module?

https://www.gnu.org/software/guile/docs/docs-1.8/guile-ref/Using-Guile-Modules.html#Using-Guile-Modules 
doesn't seem to indicate any help, but I can't imagine there's no way to 
load variable modules at runtime.

Any suggestions?
Thanks
Urs