diff --git a/jscomp/bsb/bsb_log.ml b/jscomp/bsb/bsb_log.ml
index 74ed068d8c..06401aaa69 100644
--- a/jscomp/bsb/bsb_log.ml
+++ b/jscomp/bsb/bsb_log.ml
@@ -37,17 +37,17 @@ let get_color_enabled () =
   in
   colorful
 
-let color_functions : Format.formatter_tag_functions =
+let color_functions : Format.formatter_stag_functions =
   {
-    mark_open_tag =
+    mark_open_stag =
       (fun s ->
         if get_color_enabled () then Ext_color.ansi_of_tag s
         else Ext_string.empty);
-    mark_close_tag =
+    mark_close_stag =
       (fun _ ->
         if get_color_enabled () then Ext_color.reset_lit else Ext_string.empty);
-    print_open_tag = (fun _ -> ());
-    print_close_tag = (fun _ -> ());
+    print_open_stag = (fun _ -> ());
+    print_close_stag = (fun _ -> ());
   }
 
 (* let set_color ppf =
@@ -56,8 +56,8 @@ let color_functions : Format.formatter_tag_functions =
 let setup () =
   Format.pp_set_mark_tags Format.std_formatter true;
   Format.pp_set_mark_tags Format.err_formatter true;
-  Format.pp_set_formatter_tag_functions Format.std_formatter color_functions;
-  Format.pp_set_formatter_tag_functions Format.err_formatter color_functions
+  Format.pp_set_formatter_stag_functions Format.std_formatter color_functions;
+  Format.pp_set_formatter_stag_functions Format.err_formatter color_functions
 
 type level = Debug | Info | Warn | Error
 
diff --git a/jscomp/bsb/dune b/jscomp/bsb/dune
index 0c27d4e033..bdf0b9f031 100644
--- a/jscomp/bsb/dune
+++ b/jscomp/bsb/dune
@@ -2,5 +2,5 @@
  (name bsb)
  (wrapped false)
  (flags
-  (:standard -w +a-d-4-9-40-41-42-70))
+  (:standard -w +a-4-9-40-41-42-70))
  (libraries common ext str unix))
diff --git a/jscomp/bsb_exe/dune b/jscomp/bsb_exe/dune
index 3e057d3f5c..e75592a479 100644
--- a/jscomp/bsb_exe/dune
+++ b/jscomp/bsb_exe/dune
@@ -2,5 +2,5 @@
  (name rescript_main)
  (public_name rescript)
  (flags
-  (:standard -w +a-d-4-9-40-41-42-70))
+  (:standard -w +a-4-9-40-41-42-70))
  (libraries bsb common ext str unix))
diff --git a/jscomp/ext/ext_color.ml b/jscomp/ext/ext_color.ml
index 5a34e5c67f..d5ed3bb166 100644
--- a/jscomp/ext/ext_color.ml
+++ b/jscomp/ext/ext_color.ml
@@ -59,11 +59,11 @@ let code_of_style = function
 (** TODO: add more styles later *)
 let style_of_tag s =
   match s with
-  | "error" -> [ Bold; FG Red ]
-  | "warning" -> [ Bold; FG Magenta ]
-  | "info" -> [ Bold; FG Yellow ]
-  | "dim" -> [ Dim ]
-  | "filename" -> [ FG Cyan ]
+  | Format.String_tag "error" -> [ Bold; FG Red ]
+  | Format.String_tag "warning" -> [ Bold; FG Magenta ]
+  | Format.String_tag "info" -> [ Bold; FG Yellow ]
+  | Format.String_tag "dim" -> [ Dim ]
+  | Format.String_tag "filename" -> [ FG Cyan ]
   | _ -> []
 
 let ansi_of_tag s =
diff --git a/jscomp/ext/ext_color.mli b/jscomp/ext/ext_color.mli
index 200d011a26..d2aa148455 100644
--- a/jscomp/ext/ext_color.mli
+++ b/jscomp/ext/ext_color.mli
@@ -26,7 +26,7 @@ type color = Black | Red | Green | Yellow | Blue | Magenta | Cyan | White
 
 type style = FG of color | BG of color | Bold | Dim
 
-val ansi_of_tag : string -> string
+val ansi_of_tag : Format.stag -> string
 (** Input is the tag for example `@{<warning>@}` return escape code *)
 
 val reset_lit : string