diff --git a/gnu/packages/chemistry.scm b/gnu/packages/chemistry.scm
index 065d75da6e..fb6d6fc27f 100644
--- a/gnu/packages/chemistry.scm
+++ b/gnu/packages/chemistry.scm
@@ -435,7 +435,8 @@ (define-public gromacs
 interactions (that usually dominate simulations) many groups are also using it
 for research on non-biological systems, e.g. polymers.  GROMACS supports all the
 usual algorithms you expect from a modern molecular dynamics implementation.")
-    (license license:lgpl2.1+)))
+    (license license:lgpl2.1+)
+    (properties '((tunable? . #t)))))
 
 (define-public openbabel
   (package