diff --git a/build-aux/pre-inst-env.in b/build-aux/pre-inst-env.in
index b8ef1151..59258dfd 100644
--- a/build-aux/pre-inst-env.in
+++ b/build-aux/pre-inst-env.in
@@ -48,6 +48,9 @@ export bindir
 GUIX_PACKAGE_PATH="$abs_top_srcdir/guix${GUIX_PACKAGE_PATH:+:}$GUIX_PACKAGE_PATH"
 export GUIX_PACKAGE_PATH
 
+MES_UNINSTALLED=1
+export MES_UNINSTALLED
+
 LANG=
 LC_ALL=
 
diff --git a/module/mescc/mescc.scm b/module/mescc/mescc.scm
index 9ef23d7d..6f334945 100644
--- a/module/mescc/mescc.scm
+++ b/module/mescc/mescc.scm
@@ -267,11 +267,21 @@
 (define* (arch-find options file-name #:key kernel)
   (let* ((srcdest (or (getenv "srcdest") ""))
          (srcdir-lib (string-append srcdest "lib"))
+         (srcdir-mescc-lib (string-append srcdest "mescc-lib"))
+         (libdir (option-ref options 'libdir "lib"))
+         (libdir-mescc (string-append
+                        (dirname (option-ref options 'libdir "lib"))
+                        "/mescc-lib"))
          (arch (string-append (arch-get options) "-mes"))
-         (path (cons* "."
-                      srcdir-lib
-                      (option-ref options 'libdir "lib")
-                      (filter-map (multi-opt 'library-dir) options)))
+         (path (append (if (getenv "MES_UNINSTALLED")
+                           (list srcdir-mescc-lib
+                                 srcdir-lib
+                                 libdir-mescc)
+                           '())
+                       (list libdir)
+                       (or (and=> (getenv "LIBRARY_PATH")
+                                  (cut string-split <> #\:)) '())
+                       (filter-map (multi-opt 'library-dir) options)))
          (arch-file-name (string-append arch "/" file-name))
          (arch-file-name (if kernel (string-append kernel "/" arch-file-name)
                              arch-file-name))
diff --git a/scripts/mescc.in b/scripts/mescc.in
index 0780968a..039f1f4c 100644
--- a/scripts/mescc.in
+++ b/scripts/mescc.in
@@ -37,6 +37,11 @@ export MES_PREFIX
 GUILE_LOAD_PATH=@guile_site_dir@${GUILE_LOAD_PATH+:}${GUILE_LOAD_PATH}
 export GUILE_LOAD_PATH
 
+if test -n "$MES_UNINSTALLED"; then
+    includedir=${includedir-${abs_top_srcdir}/include}
+    libdir=${libdir-${abs_top_builddir}/lib}
+fi
+
 MES=${MES-@prefix@/bin/mes}
 bindir=${bindir-@bindir@}
 includedir=${includedir-@includedir@}