diff --git a/configure b/configure
index c5cf4ab2..1a98dc1d 100755
--- a/configure
+++ b/configure
@@ -216,6 +216,10 @@ Usage: ./configure [OPTION]...
          (verbose? (option-ref options 'verbose #f))
          (with-courage? (option-ref options 'with-courage #f)))
     (set! *verbose?* verbose?)
+    (check-version 'guile '(2 0))
+    (check-version HEX2 '(0 0))
+    (check-version 'nyacc '(0 78 0) #:command (string-append GUILE " -c '(use-modules (nyacc lalr)) (display *nyacc-version*)'"))
+
     (check-version 'bash '(4 0))
     (when (and (not (member ARCH '("i686" "x86_64"))) (not with-courage?))
           (stderr "platform not supported: ~a, try --with-courage\n" ARCH)
@@ -227,12 +231,8 @@ Usage: ./configure [OPTION]...
       (check-header-c "limits.h" "linux-headers"))
     (if (not (check-version CC32 '(4 8) #:optional? #t))
         (set! CC32 #f))
-    (check-version 'guile '(2 0))
     (check-version 'make '(4 0))
     (check-version 'perl '(5))
-    (check-version 'nyacc '(0 78 0) #:command (string-append GUILE " -c '(use-modules (nyacc lalr)) (display *nyacc-version*)'"))
-    (if (not (check-version HEX2 '(0) #:optional? #t))
-        (set! HEX2 #f))
 
     (when (pair? required)
       (stderr "\nMissing dependencies [~a], run\n\n" ((->string ", ") required))
diff --git a/guix.scm b/guix.scm
index 2443abd3..47f615ba 100644
--- a/guix.scm
+++ b/guix.scm
@@ -81,7 +81,7 @@
         (_ #f)))))
 
 (define-public mes
-  (let ((commit "7fdca75d2188b28df806b34ec92627d57aafa9ae")
+  (let ((commit "ec072e8625e72b89301ad1746d839c6529188b6f")
         (revision "0")
         (triplet "i686-unknown-linux-gnu")
         (version "0.7"))
@@ -95,11 +95,12 @@
                       (commit commit)))
                 (file-name (string-append name "-" version))
                 (sha256
-                 (base32 "0fvzr1ai2rmi46zdi5b2bdjb6s8ip78mkmsk02yxl46rajmp2pb1"))))
+                 (base32 "0g9xqqpmj8319hc1931bycj88p16iw50w5rakax3jdj01gr0x6i7"))))
       (build-system gnu-build-system)
       (supported-systems '("i686-linux" "x86_64-linux"))
       (propagated-inputs
-       `(("nyacc" ,nyacc)))
+       `(("mescc-tools" ,mescc-tools)
+         ("nyacc" ,nyacc)))
       (native-inputs
        `(("guile" ,guile-2.2)
          ,@(if (string-prefix? "x86_64-linux" (or (%current-target-system)