diff --git a/dune-project b/dune-project
index 94b7ee7c01d..1c0f90cf6e3 100644
--- a/dune-project
+++ b/dune-project
@@ -156,7 +156,9 @@ understood by dune language."))
   (csexp (>= 1.5.0))
   (lwt (>= 5.3.0))
   base-unix)
- (description "Specialization of dune-rpc to Lwt"))
+ (description "Specialization of dune-rpc to Lwt")
+ (conflicts
+   (result (< 1.5))))
 
 (package
  (name dyn)
diff --git a/dune-rpc-lwt.opam b/dune-rpc-lwt.opam
index c69be4d433b..efda7b33caa 100644
--- a/dune-rpc-lwt.opam
+++ b/dune-rpc-lwt.opam
@@ -16,6 +16,9 @@ depends: [
   "base-unix"
   "odoc" {with-doc}
 ]
+conflicts: [
+  "result" {< "1.5"}
+]
 dev-repo: "git+https://github.com/ocaml/dune.git"
 build: [
   ["dune" "subst"] {dev}