ocamlPackages.camomile: append version to META file

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

@@ -1,4 +1,4 @@
-{ lib, fetchFromGitHub, buildDunePackage, cppo }:
+{ lib, fetchFromGitHub, buildDunePackage, ocaml, cppo }:
 
 buildDunePackage rec {
   pname = "camomile";
@@ -23,6 +23,10 @@ buildDunePackage rec {
     runHook postConfigure
   '';
 
+  postInstall = ''
+    echo "version = \"${version}\"" >> $out/lib/ocaml/${ocaml.version}/site-lib/camomile/META
+  '';
+
   meta = {
     inherit (src.meta) homepage;
     maintainers = [ lib.maintainers.vbgl ];