diff --git a/pkgs/applications/science/logic/coq/HEAD.nix b/pkgs/applications/science/logic/coq/HEAD.nix
new file mode 100644
index 00000000000..c103b8b4769
--- /dev/null
+++ b/pkgs/applications/science/logic/coq/HEAD.nix
@@ -0,0 +1,57 @@
+# - coqide compilation can be disabled by setting lablgtk to null;
+
+{stdenv, fetchgit, pkgconfig, ocaml, findlib, camlp5, ncurses, lablgtk ? null}:
+
+let 
+  version = "8.5pre-fff9e2f7";
+  buildIde = lablgtk != null;
+  ideFlags = if buildIde then "-lablgtkdir ${lablgtk}/lib/ocaml/*/site-lib/lablgtk2 -coqide opt" else "";
+  idePath = if buildIde then ''
+    CAML_LD_LIBRARY_PATH=${lablgtk}/lib/ocaml/3.12.1/site-lib/stublibs
+  '' else "";
+in
+
+stdenv.mkDerivation {
+  name = "coq-${version}";
+
+  src = fetchgit {
+    url = git://scm.gforge.inria.fr/coq/coq.git;
+    rev = "21994cc4c617582f4f94577c1c582a7b51b7770b";
+    sha256 = "12kadlmyh9bspn9kds36pwrq77d0widrk5q43wyrgb8y9zrnyz61";
+  };
+
+  buildInputs = [ pkgconfig ocaml findlib camlp5 ncurses lablgtk ];
+
+  postPatch = ''
+    UNAME=$(type -tp uname)
+    RM=$(type -tp rm)
+    substituteInPlace configure --replace "/bin/uname" "$UNAME"
+    substituteInPlace tools/beautify-archive --replace "/bin/rm" "$RM"
+  '';
+
+  preConfigure = ''
+    buildFlagsArray=(${idePath})
+    configureFlagsArray=(
+      -opt
+      ${ideFlags}
+    )
+  '';
+
+  prefixKey = "-prefix ";
+
+  buildFlags = "revision coq coqide";
+
+  meta = {
+    description = "Coq proof assistant";
+    longDescription = ''
+      Coq is a formal proof management system.  It provides a formal language
+      to write mathematical definitions, executable algorithms and theorems
+      together with an environment for semi-interactive development of
+      machine-checked proofs.
+    '';
+    homepage = "http://coq.inria.fr";
+    license = "LGPL";
+    maintainers = with stdenv.lib.maintainers; [ roconnor thoughtpolice ];
+    platforms = stdenv.lib.platforms.unix;
+  };
+}
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 4eb24adc0a8..6dbaed7b29f 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -10810,6 +10810,11 @@ let
     camlp5 = ocamlPackages.camlp5_transitional;
   };
 
+  coq_HEAD = callPackage ../applications/science/logic/coq/HEAD.nix {
+    inherit (ocamlPackages) findlib lablgtk;
+    camlp5 = ocamlPackages.camlp5_transitional;
+  };
+
   coq_8_3 = callPackage ../applications/science/logic/coq/8.3.nix {
     inherit (ocamlPackages) findlib lablgtk;
     camlp5 = ocamlPackages.camlp5_transitional;