diff --git a/petr4.opam b/petr4.opam
index 20083a080..5f50c73f8 100644
--- a/petr4.opam
+++ b/petr4.opam
@@ -17,9 +17,9 @@ depends: [
   "ocaml" {>= "4.04.0"}
   "dune"
   "menhir"
+  "ANSITerminal"
   "bignum"
   "core"
-  "core_extended"
   "ppx_deriving_yojson"
   "ppx_jane"
   "yojson"