diff --git a/caisar.opam b/caisar.opam
index 68164a99e7f3b4e8dc99e51ff500b11bcc599fd6..adce2f75393812bb747e7859ea7eec9e2fba2a87 100644
--- a/caisar.opam
+++ b/caisar.opam
@@ -11,6 +11,7 @@ depends: [
   "logs" {>= "0.7.0"}
   "ppx_deriving" {>= "5.1"}
   "yojson" {>= "1.7.0"}
+  "menhirLib" {>= "20210310"}
   "odoc" {with-doc}
 ]
 build: [
diff --git a/dune-project b/dune-project
index fa89e5fc190b149cc113dba4c594850cb3fdf26c..908fc1e0ee52347e4c0263fe8eca540d93ef8e9d 100644
--- a/dune-project
+++ b/dune-project
@@ -18,5 +18,6 @@
    (logs (>= 0.7.0))
    (ppx_deriving (>= 5.1))
    (yojson (>= 1.7.0))
+   (menhirLib (>= 20210310))
   )
 )