diff --git a/pkgs/development/ocaml-modules/cohttp/async.nix b/pkgs/development/ocaml-modules/cohttp/async.nix
index 23e6f4f10a1..246397b6081 100644
--- a/pkgs/development/ocaml-modules/cohttp/async.nix
+++ b/pkgs/development/ocaml-modules/cohttp/async.nix
@@ -9,6 +9,7 @@ else
 
 	buildDunePackage {
 		pname = "cohttp-async";
+		useDune2 = true;
 		inherit (cohttp) version src;
 
 		buildInputs = [ ppx_sexp_conv ];
diff --git a/pkgs/development/ocaml-modules/conduit/async.nix b/pkgs/development/ocaml-modules/conduit/async.nix
index 1c5834c415a..f16819ed8ae 100644
--- a/pkgs/development/ocaml-modules/conduit/async.nix
+++ b/pkgs/development/ocaml-modules/conduit/async.nix
@@ -1,4 +1,4 @@
-{ stdenv, buildDunePackage, async, ppx_sexp_conv, conduit }:
+{ stdenv, buildDunePackage, async, async_ssl, ppx_sexp_conv, conduit }:
 
 if !stdenv.lib.versionAtLeast conduit.version "1.0"
 then conduit
@@ -6,11 +6,12 @@ else
 
 buildDunePackage {
 	pname = "conduit-async";
+	useDune2 = true;
 	inherit (conduit) version src;
 
 	buildInputs = [ ppx_sexp_conv ];
 
-	propagatedBuildInputs = [ async conduit ];
+	propagatedBuildInputs = [ async async_ssl conduit ];
 
 	meta = conduit.meta // {
 		description = "A network connection establishment library for Async";