diff --git a/guix/derivations.scm b/guix/derivations.scm
index 731f1f698f..bd0af320c4 100644
--- a/guix/derivations.scm
+++ b/guix/derivations.scm
@@ -708,7 +708,8 @@ (define derivation-hash            ; `hashDerivationModulo' in derivations.cc
 (define* (derivation store name builder args
                      #:key
                      (system (%current-system)) (env-vars '())
-                     (inputs '()) (outputs '("out"))
+                     (inputs '()) (sources '())
+                     (outputs '("out"))
                      hash hash-algo recursive?
                      references-graphs
                      allowed-references disallowed-references
@@ -833,6 +834,8 @@ (define (env-vars-with-empty-outputs env-vars)
 
   (define input->derivation-input
     (match-lambda
+      ((? derivation-input? input)
+       input)
       (((? derivation? drv))
        (make-derivation-input drv '("out")))
       (((? derivation? drv) sub-drvs ...)
@@ -858,7 +861,8 @@ (define input->source
                                                           hash recursive?)))
                           (sort outputs string<?)))
          (sources    (sort (delete-duplicates
-                            (filter-map input->source inputs))
+                            (append (filter-map input->source inputs)
+                                    sources))
                            string<?))
          (inputs     (sort (coalesce-duplicate-inputs
                             (filter-map input->derivation-input inputs))