diff --git a/gnu/packages/maths.scm b/gnu/packages/maths.scm
index b20cec5440..8d0c10697f 100644
--- a/gnu/packages/maths.scm
+++ b/gnu/packages/maths.scm
@@ -8,7 +8,7 @@
 ;;; Copyright © 2015, 2016, 2017, 2018 Ricardo Wurmus <rekado@elephly.net>
 ;;; Copyright © 2015 Sou Bunnbu <iyzsong@gmail.com>
 ;;; Copyright © 2015 Mark H Weaver <mhw@netris.org>
-;;; Copyright © 2015, 2016, 2017 Efraim Flashner <efraim@flashner.co.il>
+;;; Copyright © 2015, 2016, 2017, 2018 Efraim Flashner <efraim@flashner.co.il>
 ;;; Copyright © 2015 Fabian Harfert <fhmgufs@web.de>
 ;;; Copyright © 2016 Roel Janssen <roel@gnu.org>
 ;;; Copyright © 2016 Kei Kebreau <kkebreau@posteo.net>
@@ -259,14 +259,14 @@ routines that have been extracted from the V8 JavaScript engine.")
 (define-public dionysus
   (package
     (name "dionysus")
-    (version "1.3.0")
+    (version "1.4.0")
     (source (origin
               (method url-fetch)
               (uri (string-append "mirror://gnu/dionysus/dionysus-" version
-                                  ".tar.gz"))
+                                  ".tar.xz"))
               (sha256
                (base32
-                "1aqnvw6z33bzqgd1ga571pnx6vq2zrkckm1cz91grv45h4jr9vgs"))))
+                "194pzs1mlsj4ww6v37qq3961h5hckm5h805cv0r14xj3g9wfx2sk"))))
     (build-system gnu-build-system)
     (inputs `(("tcl" ,tcl)))                      ;for 'tclsh'
     (synopsis "Local search for universal constants and scientific values")