> +       ;; FIXME: tests are not run
> +       #:test-dir "src/test"

Any news?  If not, we can add groovy-swing like it is now.  But it would be interesting.

> +       #:phases
> +       (modify-phases %standard-phases
> +         (add-before 'configure 'chdir
> +           (lambda _
> +             (chdir "subprojects/groovy-swing")))

#t

LGTM!