diff --git a/pkgs/development/ocaml-modules/carton/default.nix b/pkgs/development/ocaml-modules/carton/default.nix
index b075ea53021a..c3d7204f3635 100644
--- a/pkgs/development/ocaml-modules/carton/default.nix
+++ b/pkgs/development/ocaml-modules/carton/default.nix
@@ -11,10 +11,11 @@ buildDunePackage rec {
   version = "0.6.0";
 
   minimalOCamlVersion = "4.08";
+  duneVersion = "3";
 
   src = fetchurl {
     url = "https://github.com/mirage/ocaml-git/releases/download/${pname}-v${version}/git-${pname}-v${version}.tbz";
-    sha256 = "sha256-NAm4Xq7L0Dgynr8cKZQ356M4GR6D19LbCRxvnSlIf1U=";
+    hash = "sha256-NAm4Xq7L0Dgynr8cKZQ356M4GR6D19LbCRxvnSlIf1U=";
   };
 
   patches = [
diff --git a/pkgs/development/ocaml-modules/carton/git.nix b/pkgs/development/ocaml-modules/carton/git.nix
index 7e08e69543d7..b361ee1447b2 100644
--- a/pkgs/development/ocaml-modules/carton/git.nix
+++ b/pkgs/development/ocaml-modules/carton/git.nix
@@ -9,6 +9,7 @@ buildDunePackage {
   pname = "carton-git";
 
   inherit (carton) version src postPatch;
+  duneVersion = "3";
 
   propagatedBuildInputs = [
     carton
diff --git a/pkgs/development/ocaml-modules/carton/lwt.nix b/pkgs/development/ocaml-modules/carton/lwt.nix
index 2c0cf34ae5a4..60e45823eb50 100644
--- a/pkgs/development/ocaml-modules/carton/lwt.nix
+++ b/pkgs/development/ocaml-modules/carton/lwt.nix
@@ -11,6 +11,7 @@ buildDunePackage {
   pname = "carton-lwt";
 
   inherit (carton) version src postPatch;
+  duneVersion = "3";
 
   propagatedBuildInputs = [
     carton
diff --git a/pkgs/development/ocaml-modules/decompress/default.nix b/pkgs/development/ocaml-modules/decompress/default.nix
index a8b460f426ba..c67cfac5410a 100644
--- a/pkgs/development/ocaml-modules/decompress/default.nix
+++ b/pkgs/development/ocaml-modules/decompress/default.nix
@@ -1,22 +1,24 @@
 { lib, fetchurl, buildDunePackage
 , checkseum, optint, cmdliner
 , bigstringaf, alcotest, camlzip, base64, ctypes, fmt, crowbar, rresult
+, astring, bos
 }:
 
 buildDunePackage rec {
   pname = "decompress";
-  version = "1.5.1";
+  version = "1.5.2";
 
   minimalOCamlVersion = "4.08";
+  duneVersion = "3";
 
   src = fetchurl {
     url = "https://github.com/mirage/decompress/releases/download/v${version}/decompress-${version}.tbz";
-    sha256 = "sha256-y/OVojFxhksJQQvvtS38SF7ZnMEQhAtwDey0ISwypP4=";
+    hash = "sha256-qMmmuhMlFNVq02JvvV55EkhEg2AQNQ7hYdQ7spv1di4=";
   };
 
   buildInputs = [ cmdliner ];
   propagatedBuildInputs = [ optint checkseum ];
-  nativeCheckInputs = [ alcotest bigstringaf ctypes fmt camlzip base64 crowbar rresult ];
+  nativeCheckInputs = [ alcotest astring bigstringaf bos ctypes fmt camlzip base64 crowbar rresult ];
   doCheck = true;
 
   meta = {
diff --git a/pkgs/development/ocaml-modules/pbkdf/default.nix b/pkgs/development/ocaml-modules/pbkdf/default.nix
index 41dc6394e84c..5dedd200a825 100644
--- a/pkgs/development/ocaml-modules/pbkdf/default.nix
+++ b/pkgs/development/ocaml-modules/pbkdf/default.nix
@@ -10,12 +10,14 @@ buildDunePackage rec {
   pname = "pbkdf";
   version = "1.2.0";
 
+  duneVersion = "3";
+
   src = fetchzip {
     url = "https://github.com/abeaumont/ocaml-pbkdf/archive/${version}.tar.gz";
     sha256 = "sha256-dGi4Vw+7VBpK/NpJ6zdpogm+E6G/oJovXCksJBSmqjI=";
   };
 
-  minimalOCamlVersion = "4.07";
+  minimalOCamlVersion = "4.08";
   propagatedBuildInputs = [ cstruct mirage-crypto ];
   nativeCheckInputs = [ alcotest ];
   doCheck = true;