diff --git a/CHANGES.md b/CHANGES.md
index 1cb363cbe..2ab336785 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,5 +1,6 @@
-UNRELEASED
+merlin 5.1
 ==========
+Tue Jun 18 12:00:42 CEST 2024
 
   + merlin binary
     - Support project-wide occurrences queries using index files (#1766)
diff --git a/merlin.opam b/merlin.opam
index bd1093a7f..ff3f8f67e 100644
--- a/merlin.opam
+++ b/merlin.opam
@@ -15,6 +15,7 @@ depends: [
   "dune" {>= "3.0.0"}
   "merlin-lib" {= version}
   "dot-merlin-reader" {>= "5.0"}
+  "ocaml-index" {>= "1.0" & post}
   "yojson" {>= "2.0.0"}
   "conf-jq" {with-test}
   "ppxlib" {with-test}
@@ -70,3 +71,6 @@ See https://github.com/OCamlPro/opam-user-setup
 "
   {success & !user-setup:installed}
 ]
+pin-depends: [
+  ["ocaml-index.1.0"  "git+https://github.com/voodoos/ocaml-index#82b08987921884daeeb5dccc345a2dcb667fe113"]
+]
diff --git a/src/analysis/occurrences.ml b/src/analysis/occurrences.ml
index a57200179..f0db4a9a1 100644
--- a/src/analysis/occurrences.ml
+++ b/src/analysis/occurrences.ml
@@ -230,8 +230,9 @@ let locs_of ~config ~env ~typer_result ~pos ~scope path =
       log ~title:"occurrences" "Found %i locs" (Lid_set.cardinal locs);
       Lid_set.elements locs
       |> List.filter_map ~f:(fun {Location.txt; loc} ->
+        let lid = try Longident.head txt with _ -> "not flat lid" in
         log ~title:"occurrences" "Found occ: %s %a"
-          (Longident.head txt) Logger.fmt (Fun.flip Location.print_loc loc);
+          lid Logger.fmt (Fun.flip Location.print_loc loc);
         let loc = last_loc loc txt in
         let fname = loc.Location.loc_start.Lexing.pos_fname in
         if not (Filename.is_relative fname) then Some loc else