diff --git a/nix/default.nix b/nix/default.nix
index 3525a5997a81998fbf31c5cad64289ef7ae0f622..24d4be50a0ed05a6ef8aa435d38180a3c9e8dc6a 100644
--- a/nix/default.nix
+++ b/nix/default.nix
@@ -7,7 +7,5 @@ plugins.helpers.simple_plugin
      name = "frama-clang";
      deps = [ pkgs.llvmPackages_7.clang-unwrapped pkgs.llvm_7 pkgs.gnused ];
      opamPackages = [ "camlp4" ];
-     postPatch = ''
-     sed -i Makefile.config.in -e "s&@CLANG_INCDIR@&${pkgs.llvmPackages_7.clang-unwrapped}/include&"
-     '';
+     configure_options = "-with-clang-includedir=${pkgs.llvmPackages_7.clang-unwrapped}";
    }
diff --git a/nix/frama-ci.nix b/nix/frama-ci.nix
index f91f77e3795dff01085099b6f9744ded8d473354..edea5249cbae96be24dc83bc2080c303a40bf64c 100644
--- a/nix/frama-ci.nix
+++ b/nix/frama-ci.nix
@@ -5,7 +5,7 @@ let
     src = builtins.fetchGit {
             "url" = "https://bobot:${password}@git.frama-c.com/frama-c/Frama-CI.git";
             "name" = "Frama-CI";
-            "rev" = "8bb9694075309fb38c7d7cb28e831132de34ba04";
+            "rev" = "a99329415497d43b9bd263bbbbbded12e08f518b";
             "ref" = "feature/frama-clang-ci";
     };
  in