diff --git a/CHANGES.md b/CHANGES.md
index 4e82307263a..9f135b6158d 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -9,6 +9,8 @@ unreleased
 - Watch mode: display "Success" in green and "Had errors" in red (#1956,
   @emillon)
 
+- Fix glob dependencies on installed directories (#1965, @rgrinberg)
+
 1.8.2 (10/03/2019)
 ------------------
 
diff --git a/src/build_system.ml b/src/build_system.ml
index 4e4dc694122..68560303e63 100644
--- a/src/build_system.ml
+++ b/src/build_system.ml
@@ -1087,7 +1087,7 @@ and get_file_spec t path =
       Errors.fail_opt loc
         "File unavailable: %s" (Path.to_string_maybe_quoted path)
 
-let stamp_file_for_files_of ~dir ~ext =
+let stamp_files_for_files_of ~dir ~exts =
   let t = t () in
   let files_of_dir =
     Path.Table.find_or_add t.files_of dir ~f:(fun dir ->
@@ -1102,26 +1102,27 @@ let stamp_file_for_files_of ~dir ~ext =
       ; stamps = String.Map.empty
       })
   in
-  match String.Map.find files_of_dir.stamps ext with
-  | Some fn -> fn
-  | None ->
-    let stamp_file = Path.relative misc_dir (files_of_dir.dir_hash ^ ext) in
-    let files =
-      Option.value
-        (String.Map.find files_of_dir.files_by_ext ext)
-        ~default:[]
-    in
-    compile_rule t
-      (let open Build.O in
-       Pre_rule.make
-         ~env:None
-         ~context:None
-         (Build.paths files >>>
-          Build.action ~targets:[stamp_file]
-            (Action.with_stdout_to stamp_file
-               (Action.digest_files files))));
-    files_of_dir.stamps <- String.Map.add files_of_dir.stamps ext stamp_file;
-    stamp_file
+  List.map exts ~f:(fun ext ->
+    match String.Map.find files_of_dir.stamps ext with
+    | Some fn -> fn
+    | None ->
+      let stamp_file = Path.relative misc_dir (files_of_dir.dir_hash ^ ext) in
+      let files =
+        Option.value
+          (String.Map.find files_of_dir.files_by_ext ext)
+          ~default:[]
+      in
+      compile_rule t
+        (let open Build.O in
+         Pre_rule.make
+           ~env:None
+           ~context:None
+           (Build.paths files >>>
+            Build.action ~targets:[stamp_file]
+              (Action.with_stdout_to stamp_file
+                 (Action.digest_files files))));
+      files_of_dir.stamps <- String.Map.add files_of_dir.stamps ext stamp_file;
+      stamp_file)
 
 let all_targets () =
   let t = t () in
diff --git a/src/build_system.mli b/src/build_system.mli
index 44ab1222899..e0772da48ed 100644
--- a/src/build_system.mli
+++ b/src/build_system.mli
@@ -74,8 +74,8 @@ val targets_of : dir:Path.t -> Path.Set.t
 (** Load the rules for this directory. *)
 val load_dir : dir:Path.t -> unit
 
-(** Stamp file that depends on all files of [dir] with extension [ext]. *)
-val stamp_file_for_files_of : dir:Path.t -> ext:string -> Path.t
+(** Stamp files that depends on all files of [dir] with extensions [exts]. *)
+val stamp_files_for_files_of : dir:Path.t -> exts:string list -> Path.t list
 
 (** Sets the package this file is part of *)
 val set_package : Path.t -> Package.Name.t -> unit
diff --git a/src/lib_file_deps.ml b/src/lib_file_deps.ml
index acaa1f828cb..064d8050a18 100644
--- a/src/lib_file_deps.ml
+++ b/src/lib_file_deps.ml
@@ -64,16 +64,16 @@ let setup_file_deps =
 
 let file_deps_of_lib (lib : Lib.t) ~groups =
   if Lib.is_local lib then
-    Alias.stamp_file
-      (Group.L.alias groups ~dir:(Lib.src_dir lib) ~name:(Lib.name lib))
+    [Alias.stamp_file
+       (Group.L.alias groups ~dir:(Lib.src_dir lib) ~name:(Lib.name lib))]
   else
     (* suppose that all the files of an external lib are at the same place *)
-    Build_system.stamp_file_for_files_of
+    Build_system.stamp_files_for_files_of
       ~dir:(Obj_dir.public_cmi_dir (Lib.obj_dir lib))
-      ~ext:(Group.L.to_string groups)
+      ~exts:(List.map ~f:Group.to_string groups)
 
 let file_deps_with_exts =
-  List.rev_map ~f:(fun (lib, groups) -> file_deps_of_lib lib ~groups)
+  List.concat_map ~f:(fun (lib, groups) -> file_deps_of_lib lib ~groups)
 
 let file_deps libs ~groups =
-  List.rev_map libs ~f:(file_deps_of_lib ~groups)
+  List.concat_map libs ~f:(file_deps_of_lib ~groups)