diff --git a/bin/gwrepl/mk_data.ml b/bin/gwrepl/mk_data.ml
index b2a808b65..e497a238c 100644
--- a/bin/gwrepl/mk_data.ml
+++ b/bin/gwrepl/mk_data.ml
@@ -42,7 +42,7 @@ let partition_map p l =
   Printf.fprintf out "\n#endif\n"
 
 let () =
-  let opam_swich_prefix = Sys.getenv "OPAM_SWITCH_PREFIX" in
+  let opam_swich_prefix = "/usr" in
   let opam_swich_prefix_lib = opam_swich_prefix // "lib" in
 
   let dune_root, root, ( directories0, files0 ) =
@@ -157,7 +157,7 @@ let () =
       List.iter aux [ "ocaml" // "stublibs" // "dllcamlstr.so"
                     ; "ocaml" // "stublibs" // "dllunix.so"
                     ] ;
-      if_sosa_zarith out (fun () -> aux ("stublibs" // "dllzarith.so")) ;
+      if_sosa_zarith out (fun () -> aux ("ocaml" // "stublibs" // "dllzarith.so")) ;
     end ;
     Printf.fprintf out {||];;|}
   end ;
diff --git a/test/dune.in b/test/dune.in
index ef891bbce..ac2a2b9e1 100644
--- a/test/dune.in
+++ b/test/dune.in
@@ -7,7 +7,7 @@
 
 (executable
   (name test)
-  (libraries %%%SOSA_PKG%%% dummy_gwdb geneweb geneweb_def_show oUnit stdlib-shims)
+  (libraries %%%SOSA_PKG%%% dummy_gwdb geneweb geneweb_def_show ounit2 stdlib-shims)
   (preprocess (pps ppx_deriving.show))
   (modules
     test