diff --git a/yocaml_yaml.opam b/yocaml_yaml.opam
index 2054d3b..945e603 100644
--- a/yocaml_yaml.opam
+++ b/yocaml_yaml.opam
@@ -29,3 +29,4 @@ depends: [
   "yocaml" {= version}
   "alcotest" {with-test}
 ]
+conflicts: [ "result" {< "1.5"} ]