diff --git a/pkgs/development/ocaml-modules/ocsigen-server/default.nix b/pkgs/development/ocaml-modules/ocsigen-server/default.nix
index 96a66874c759..67ec458a122d 100644
--- a/pkgs/development/ocaml-modules/ocsigen-server/default.nix
+++ b/pkgs/development/ocaml-modules/ocsigen-server/default.nix
@@ -37,7 +37,7 @@ buildDunePackage rec {
     ocaml_pcre xml-light
   ];
 
-  configureFlags = [ "--root $(out)" "--prefix /" ];
+  configureFlags = [ "--root $(out)" "--prefix /" "--temproot ''" ];
 
   dontAddPrefix = true;
   dontAddStaticConfigureFlags = true;
@@ -47,6 +47,10 @@ buildDunePackage rec {
     make -C src confs
   '';
 
+  postInstall = ''
+    make install.files
+  '';
+
   postFixup =
   ''
   rm -rf $out/var/run