* guix/derivations.scm (%guile-for-build): New parameter. (build-expression->derivation): New procedure. * tests/derivations.scm ("build-expression->derivation without inputs", "build-expression->derivation with one input"): New tests.
* guix/derivations.scm (%guile-for-build): New parameter. (build-expression->derivation): New procedure. * tests/derivations.scm ("build-expression->derivation without inputs", "build-expression->derivation with one input"): New tests.