how do I compile a whole Frege source tree

how do I compile a whole Frege source tree

Following the answeres to how to use multiple inline assertions in Frege I
learned how to compile two Frege modules A and B where B depends on A: you
have to compile B. If given the -make option, the compiler will figure out
that B depends on A, will find A on the sourcepath (-sp flag), and will
compile A first and then B.
However, I cannot just give all files I care about to the compiler. Giving
both A and B to the compiler failed with a "cyclic dependency" error for
me. And I also found no way to give a directory to the compiler (it just
did nothing).
This looks like I had to know the root of the dependency graph to do a
proper compilation of all need-to-be-compiled files. But
I may not know the root.
There may be many of them.
It's very difficult to do a proper build automation that way.
Is there a combination of compiler options where I can just let the
compiler compile all files in a source tree?