diff --git a/pkgs/development/ocaml-modules/cstruct/async.nix b/pkgs/development/ocaml-modules/cstruct/async.nix
new file mode 100644
index 000000000000..579f12776c08
--- /dev/null
+++ b/pkgs/development/ocaml-modules/cstruct/async.nix
@@ -0,0 +1,11 @@
+{ lib, buildDunePackage, cstruct, async_unix }:
+
+buildDunePackage rec {
+  pname = "cstruct-async";
+  inherit (cstruct) src version meta useDune2;
+
+  propagatedBuildInputs = [
+    async_unix
+    cstruct
+  ];
+}
diff --git a/pkgs/top-level/ocaml-packages.nix b/pkgs/top-level/ocaml-packages.nix
index 07191c8e96f1..c6172887833b 100644
--- a/pkgs/top-level/ocaml-packages.nix
+++ b/pkgs/top-level/ocaml-packages.nix
@@ -217,6 +217,8 @@ let
 
     cstruct = callPackage ../development/ocaml-modules/cstruct {};
 
+    cstruct-async = callPackage ../development/ocaml-modules/cstruct/async.nix { };
+
     cstruct-lwt = callPackage ../development/ocaml-modules/cstruct/lwt.nix { };
 
     cstruct-sexp = callPackage ../development/ocaml-modules/cstruct/sexp.nix {};