diff --git a/flake.nix b/flake.nix
index 5946319..2ee1ab9 100644
--- a/flake.nix
+++ b/flake.nix
@@ -32,6 +32,7 @@
               pkgs.ocamlPackages.ocaml-lsp
               pkgs.ocamlPackages.ocamlformat
               pkgs.ocamlPackages.ocamlformat-rpc-lib
+              pkgs.ocamlPackages.utop
             ];
           };
         };