diff --git a/pkgs/development/ocaml-modules/cstruct/unix.nix b/pkgs/development/ocaml-modules/cstruct/unix.nix
index fb7612b5f05e..604ad4fb083b 100644
--- a/pkgs/development/ocaml-modules/cstruct/unix.nix
+++ b/pkgs/development/ocaml-modules/cstruct/unix.nix
@@ -1,4 +1,8 @@
-{ buildDunePackage, cstruct }:
+{ lib, buildDunePackage, cstruct }:
+
+if !lib.versionAtLeast (cstruct.version or "1") "3"
+then cstruct
+else
 
 buildDunePackage {
 	pname = "cstruct-unix";