diff --git a/lib/compiler/Phases.ml b/lib/compiler/Phases.ml
index 9d950fc..ff50db8 100644
--- a/lib/compiler/Phases.ml
+++ b/lib/compiler/Phases.ml
@@ -379,11 +379,14 @@ let implant ~(forest : State.t) (foreign : Config.foreign) =
 
 let implant_foreign ~(forest : State.t) : _ =
   let total = List.length forest.config.foreign in
-  forest.log.debug ~src:Log.Src.compiler (fun m ->
-      m "implanting %i foreign forests" total);
-  let@ foreign =
-    Eio.Fiber.List.filter_map ~max_fibers @~ forest.config.foreign
-  in
-  implant ~forest foreign |> function Ok () -> None | Error e -> Some e
+  if total = 0 then []
+  else begin
+    forest.log.debug ~src:Log.Src.compiler (fun m ->
+        m "implanting %i foreign forests" total);
+    let@ foreign =
+      Eio.Fiber.List.filter_map ~max_fibers @~ forest.config.foreign
+    in
+    implant ~forest foreign |> function Ok () -> None | Error e -> Some e
+  end
 
 let render _forest = []