diff --git a/pkgs/development/ocaml-modules/posix/base.nix b/pkgs/development/ocaml-modules/posix/base.nix
index a6fe690ebcc..ab78d3737f9 100644
--- a/pkgs/development/ocaml-modules/posix/base.nix
+++ b/pkgs/development/ocaml-modules/posix/base.nix
@@ -4,16 +4,17 @@
 
 buildDunePackage rec {
   pname = "posix-base";
-  version = "2.0.0";
+  version = "2.0.2";
 
   src = fetchFromGitHub {
     owner = "savonet";
     repo = "ocaml-posix";
     rev = "v${version}";
-    sha256 = "18px8hfqcfy2lk8105ki3hrxxigs44gs046ba0fqda6wzd0hr82b";
+    hash = "sha256-xxNaPJZdcW+KnT7rYUuC7ZgmHtXTppZG2BOmpKweC/U=";
   };
 
-  useDune2 = true;
+  duneVersion = "3";
+  minimalOCamlVersion = "4.08";
 
   propagatedBuildInputs = [ ctypes integers ];
 
diff --git a/pkgs/development/ocaml-modules/posix/socket.nix b/pkgs/development/ocaml-modules/posix/socket.nix
index 69a469bbece..c998965a618 100644
--- a/pkgs/development/ocaml-modules/posix/socket.nix
+++ b/pkgs/development/ocaml-modules/posix/socket.nix
@@ -3,7 +3,9 @@
 buildDunePackage {
   pname = "posix-socket";
 
-  inherit (posix-base) version src useDune2;
+  inherit (posix-base) version src;
+
+  duneVersion = "3";
 
   propagatedBuildInputs = [ posix-base ];
 
diff --git a/pkgs/development/ocaml-modules/posix/time2.nix b/pkgs/development/ocaml-modules/posix/time2.nix
index b4601c162bd..c82da776b8f 100644
--- a/pkgs/development/ocaml-modules/posix/time2.nix
+++ b/pkgs/development/ocaml-modules/posix/time2.nix
@@ -5,6 +5,8 @@ buildDunePackage {
 
   inherit (posix-base) version src;
 
+  duneVersion = "3";
+
   propagatedBuildInputs = [ posix-base posix-types unix-errno ];
 
   doCheck = true;
diff --git a/pkgs/development/ocaml-modules/posix/types.nix b/pkgs/development/ocaml-modules/posix/types.nix
index 2512fe892c1..c346ea86ac7 100644
--- a/pkgs/development/ocaml-modules/posix/types.nix
+++ b/pkgs/development/ocaml-modules/posix/types.nix
@@ -3,9 +3,10 @@
 buildDunePackage {
   pname = "posix-types";
 
-  inherit (posix-base) version src useDune2;
+  inherit (posix-base) version src;
 
-  minimumOCamlVersion = "4.03";
+  minimalOCamlVersion = "4.03";
+  duneVersion = "3";
 
   propagatedBuildInputs = [ posix-base ];