For what it is worth, the Kawa search algorithm for library sources is:
https://www.gnu.org/software/kawa/Importing.html#Searching-for-source-files

The default when resolving for (import (foo bar)) is to look for "foo/bar"
with a default extension, which is ".scm" - hence "foo/bar.scm".
This is relative to the current path.

Kawa supports ".sld" files and the define-library form. However, the Kawa-native
style is to treat a source file as an implicit library (or module as I also call it):
A library is just a file with definitions along with 'export' and 'import' forms.
Much less file-clutter, in my opinion.

This turns out to be close to what they do in Rust, which I've been
spending some time learning-by-hacking.
--
	--Per Bothner
xxxxxx@bothner.com   http://per.bothner.com/