diff --git a/src/compilation_context.ml b/src/compilation_context.ml
index 2d302478..b43a293d 100644
--- a/src/compilation_context.ml
+++ b/src/compilation_context.ml
@@ -16,7 +16,7 @@ module Includes = struct
       let cmi_includes =
         Arg_spec.S [ iflags
                    ; Hidden_deps
-                       (Lib_deps.file_deps sctx libs ~ext:".cmi")
+                       (Lib_deps.L.file_deps sctx libs ~ext:".cmi")
                    ]
       in
       let cmx_includes =
@@ -29,9 +29,9 @@ module Includes = struct
                        ".cmi"
                      else
                        ".cmi-and-.cmx"))
-                  |> Lib_deps.file_deps_with_exts sctx
+                  |> Lib_deps.L.file_deps_with_exts sctx
                 else
-                  Lib_deps.file_deps sctx libs ~ext:".cmi-and-.cmx"
+                  Lib_deps.L.file_deps sctx libs ~ext:".cmi-and-.cmx"
               )
           ]
       in
diff --git a/src/lib_deps.ml b/src/lib_deps.ml
index 22803dcd..2e3d2924 100644
--- a/src/lib_deps.ml
+++ b/src/lib_deps.ml
@@ -17,16 +17,18 @@ let setup_file_deps_group_alias t ~dir ~exts lib =
          (lib_files_alias ~dir ~name:(Library.best_name lib) ~ext))
      |> Path.Set.of_list)
 
-let file_deps_of_lib t (lib : Lib.t) ~ext =
-  if Lib.is_local lib then
-    Alias.stamp_file
-      (lib_files_alias ~dir:(Lib.src_dir lib) ~name:(Lib.name lib) ~ext)
-  else
-    Build_system.stamp_file_for_files_of (Super_context.build_system t)
-      ~dir:(Lib.obj_dir lib) ~ext
+module L = struct
+  let file_deps_of_lib t (lib : Lib.t) ~ext =
+    if Lib.is_local lib then
+      Alias.stamp_file
+        (lib_files_alias ~dir:(Lib.src_dir lib) ~name:(Lib.name lib) ~ext)
+    else
+      Build_system.stamp_file_for_files_of (Super_context.build_system t)
+        ~dir:(Lib.obj_dir lib) ~ext
 
-let file_deps_with_exts t lib_exts =
-  List.rev_map lib_exts ~f:(fun (lib, ext) -> file_deps_of_lib t lib ~ext)
+  let file_deps_with_exts t lib_exts =
+    List.rev_map lib_exts ~f:(fun (lib, ext) -> file_deps_of_lib t lib ~ext)
 
-let file_deps t libs ~ext =
-  List.rev_map libs ~f:(file_deps_of_lib t ~ext)
+  let file_deps t libs ~ext =
+    List.rev_map libs ~f:(file_deps_of_lib t ~ext)
+end
diff --git a/src/lib_deps.mli b/src/lib_deps.mli
index 88a420e4..cfb870fa 100644
--- a/src/lib_deps.mli
+++ b/src/lib_deps.mli
@@ -1,13 +1,16 @@
 open Stdune
 
-(** [file_deps t libs ~ext] returns a list of path dependencies for all the
-    files with extension [ext] of libraries [libs]. *)
-val file_deps : Super_context.t -> Lib.L.t -> ext:string -> Path.t list
+module L : sig
 
-val file_deps_with_exts
-  :  Super_context.t
-  -> (Lib.t * string) list
-  -> Path.t list
+  (** [file_deps t libs ~ext] returns a list of path dependencies for all the
+      files with extension [ext] of libraries [libs]. *)
+  val file_deps : Super_context.t -> Lib.L.t -> ext:string -> Path.t list
+
+  val file_deps_with_exts
+    :  Super_context.t
+    -> (Lib.t * string) list
+    -> Path.t list
+end
 
 (** Setup the alias that depends on all files with a given extension
     for a library *)
diff --git a/src/lib_rules.ml b/src/lib_rules.ml
index 8e2efa06..bf7f7035 100644
--- a/src/lib_rules.ml
+++ b/src/lib_rules.ml
@@ -273,7 +273,7 @@ module Gen (P : Install_rules.Params) = struct
         [ Hidden_deps h_files
         ; Arg_spec.of_result_map requires ~f:(fun libs ->
             S [ Lib.L.c_include_flags libs ~stdlib_dir:ctx.stdlib_dir
-              ; Hidden_deps (Lib_deps.file_deps sctx libs ~ext:".h")
+              ; Hidden_deps (Lib_deps.L.file_deps sctx libs ~ext:".h")
               ])
         ]
     in