> +       #:test-exclude (list
> +;; exception from Groovy: org.codehaus.groovy.runtime.InvokerInvocationException:
> +;; groovy.lang.MissingMethodException: No signature of method:
> +;; java.util.ArrayList.each() is applicable for argument types:
> +;; (groovy.script.MapFromList$_doit_closure1) values:
> +;; [groovy.script.MapFromList$_doit_closure1@17e554d5]
> +                        "**/BSFTest.java")

If not already known upstream, could you report it there?

> +           (lambda _
> +             (chdir "subprojects/groovy-bsf")))

#t

> +         (replace 'build
> +           (lambda _
> +             (mkdir-p "build/classes")
> +             (mkdir-p "build/jar")
> +             (and
> +               (zero? (apply system* "java" "-cp" (getenv "CLASSPATH")
> +                               "org.codehaus.groovy.tools.FileSystemCompiler"
> +                               "-d" "build/classes"
> +                               "-j"; joint compilation
> +                               (find-files "src/main"
> +                                           ".*\\.(groovy|java)$")))
> +               (zero? (system* "jar" "-cf" "build/jar/groovy-bsf.jar"
> +                               "-C" "build/classes" ".")))))

If these are always exactly the same we can think about adding a build system for groovy in the future.  Doesn't have to be complicated or anything, just so it does this phase (and "check") automatically.

LGTM!