diff --git a/cohttp-async.opam b/cohttp-async.opam
index ca68676306..fd838ba36f 100644
--- a/cohttp-async.opam
+++ b/cohttp-async.opam
@@ -25,9 +25,9 @@ bug-reports: "https://github.com/mirage/ocaml-cohttp/issues"
 depends: [
   "ocaml" {>= "4.04.1"}
   "dune" {>= "1.1.0"}
-  "async_kernel" {>= "v0.13.0"}
-  "async_unix" {>= "v0.13.0"}
-  "async" {>= "v0.13.0"}
+  "async_kernel" {>= "v0.14.0"}
+  "async_unix" {>= "v0.14.0"}
+  "async" {>= "v0.14.0"}
   "base" {>= "v0.11.0"}
   "core" {with-test}
   "cohttp" {=version}
diff --git a/cohttp-async/bin/cohttp_server_async.ml b/cohttp-async/bin/cohttp_server_async.ml
index f7cb243163..c6c0e514d3 100644
--- a/cohttp-async/bin/cohttp_server_async.ml
+++ b/cohttp-async/bin/cohttp_server_async.ml
@@ -72,7 +72,7 @@ let serve ~info ~docroot ~index uri path =
   | Ok res -> return res
   | Error exn ->
     begin match Monitor.extract_exn exn with
-    | Unix.Unix_error (Unix.ENOENT, "stat", p) ->
+    | Unix.Unix_error (Unix.Error.ENOENT, "stat", p) ->
       if String.equal p ("((filename "^file_name^"))") (* Really? *)
       then Server.respond_string ~status:`Not_found
         (html_of_not_found path info)