diff --git a/opam b/opam
index acabc0f1..a3b0dfe8 100644
--- a/opam
+++ b/opam
@@ -28,6 +28,7 @@ depends: [
     "ocamlfind" {build}
     "base-bytes"
     "cppo" {build}
+    "oasis" {build}
     "ocamlbuild" {build}
 ]
 depopts: [ "sequence" "base-bigarray" "base-unix" "base-threads" ]