Add a derivation for ocaml-optcomp

pkgs/development/ocaml-modules/optcomp/default.nix

@@ -0,0 +1,25 @@
+{stdenv, fetchurl, ocaml, findlib}:
+
+stdenv.mkDerivation {
+  name = "ocaml-optcomp";
+  src = fetchurl {
+    url = https://github.com/diml/optcomp/archive/1.6.tar.gz;
+    md5 = "d3587244dba1b8b10f24d0b60a8c700d";
+    };
+  
+  createFindlibDestdir = true;
+
+  buildInputs = [ocaml findlib];
+
+
+  meta =  {
+    homepage = https://github.com/diml/optcomp;
+    description = "Optional compilation for OCaml with cpp-like directives";
+    license = "BSD";
+    platforms = ocaml.meta.platforms;
+    maintainers = [
+      stdenv.lib.maintainers.gal_bolle
+    ];
+  };
+
+}

pkgs/top-level/all-packages.nix

@@ -3381,6 +3381,8 @@ let
 
     ocaml_oasis = callPackage ../development/tools/ocaml/oasis { };
 
+    ocaml_optcomp = callPackage ../development/ocaml-modules/optcomp { };
+
     ocaml_pcre = callPackage ../development/ocaml-modules/pcre {
       inherit pcre;
     };