diff --git a/jscomp/bsb/bsb_config_parse.ml b/jscomp/bsb/bsb_config_parse.ml
index 91e10d7a56..69fcdb0523 100644
--- a/jscomp/bsb/bsb_config_parse.ml
+++ b/jscomp/bsb/bsb_config_parse.ml
@@ -25,7 +25,7 @@
 
 (* let get_list_string = Bsb_build_util.get_list_string *)
 let (//) = Ext_path.combine
-let current_package : Bsb_pkg_types.t = Global Bs_version.package_name
+
 let resolve_package cwd  package_name = 
   let x =  Bsb_pkg.resolve_bs_package ~cwd package_name  in
   {
@@ -113,6 +113,7 @@ let check_stdlib (map : json_map) cwd (*built_in_package*) =
   | None 
   | Some _ ->
     begin
+      let current_package : Bsb_pkg_types.t = Global !Bs_version.package_name in  
       if Sys.getenv_opt "RES_SKIP_STDLIB_CHECK" = None then begin 
         let stdlib_path = 
           Bsb_pkg.resolve_bs_package ~cwd current_package in 
diff --git a/jscomp/bsb/bsb_exception.ml b/jscomp/bsb/bsb_exception.ml
index d32a8d4bb1..d65f83ee83 100644
--- a/jscomp/bsb/bsb_exception.ml
+++ b/jscomp/bsb/bsb_exception.ml
@@ -57,12 +57,12 @@ let print (fmt : Format.formatter) (x : error) =
     | None -> Ext_string.empty
     | Some x -> " in " ^ x in
     let name = Bsb_pkg_types.to_string name in 
-    if Ext_string.equal name Bs_version.package_name then
+    if Ext_string.equal name !Bs_version.package_name then
       Format.fprintf fmt
       "File \"bsconfig.json\", line 1\n\
-       @{<error>Error:@} package @{<error>bs-platform@} is not found %s\n\
+       @{<error>Error:@} package @{<error>%s@} is not found %s\n\
        It's the basic, required package. If you have it installed globally,\n\
-       Please run `npm link bs-platform` to make it available" in_json
+       Please run `npm link bs-platform` to make it available" name in_json
     else
       Format.fprintf fmt
         "File \"bsconfig.json\", line 1\n\
diff --git a/jscomp/build_version.js b/jscomp/build_version.js
index f764237191..9ea96587f5 100644
--- a/jscomp/build_version.js
+++ b/jscomp/build_version.js
@@ -42,7 +42,7 @@ fs.writeFileSync(
 let version = "${version}"
 let header = 
    "// Generated by ReScript, PLEASE EDIT WITH CARE"  
-let package_name = "${name}"   
+let package_name = ref "${name}"   
     `,
   "utf8"
 );
diff --git a/jscomp/common/bs_version.ml b/jscomp/common/bs_version.ml
index dbaf0fbd0b..1810b6f64b 100644
--- a/jscomp/common/bs_version.ml
+++ b/jscomp/common/bs_version.ml
@@ -22,8 +22,8 @@
  * You should have received a copy of the GNU Lesser General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *)    
-let version = "8.4.0"
+let version = "8.5.0"
 let header = 
    "// Generated by ReScript, PLEASE EDIT WITH CARE"  
-let package_name = "bs-platform"   
+let package_name = ref "bs-platform"   
     
\ No newline at end of file
diff --git a/jscomp/common/bs_version.mli b/jscomp/common/bs_version.mli
index 3a6094e3a7..cb5c2022ec 100644
--- a/jscomp/common/bs_version.mli
+++ b/jscomp/common/bs_version.mli
@@ -26,4 +26,4 @@ val version : string
 
 val header : string 
 
-val package_name : string
\ No newline at end of file
+val package_name : string ref
\ No newline at end of file
diff --git a/jscomp/core/js_name_of_module_id.ml b/jscomp/core/js_name_of_module_id.ml
index a4282e1037..172d8f545a 100644
--- a/jscomp/core/js_name_of_module_id.ml
+++ b/jscomp/core/js_name_of_module_id.ml
@@ -34,6 +34,7 @@ let fix_path_for_windows : string -> string =
   else fun s -> s 
 
 
+(* dependency is runtime module *)  
 let get_runtime_module_path 
     (dep_module_id : Lam_module_ident.t) 
     (current_package_info : Js_packages_info.t)
diff --git a/jscomp/core/js_packages_info.ml b/jscomp/core/js_packages_info.ml
index 228e8fcf06..27eab46e07 100644
--- a/jscomp/core/js_packages_info.ml
+++ b/jscomp/core/js_packages_info.ml
@@ -56,7 +56,7 @@ type package_name  =
 
 
 
-let runtime_package_name = "bs-platform"
+
 
 
 let (//) = Filename.concat    
@@ -70,7 +70,7 @@ let runtime_dir_of_module_system (ms : module_system ) =
 let runtime_package_path 
     (ms : module_system) 
     js_file =        
-  runtime_package_name // "lib" // runtime_dir_of_module_system ms // js_file
+  !Bs_version.package_name // "lib" // runtime_dir_of_module_system ms // js_file
 
 
 type t =
@@ -86,6 +86,14 @@ let runtime_package_specs : t = {
     {module_system = NodeJS; path = "lib/js"; suffix = Js};
   ]
 }   
+
+(**
+  populated by the command line
+*)
+let runtime_test_package_specs : t = {
+  name = Pkg_runtime; 
+  module_systems = []
+}
 let same_package_by_name (x : t) (y : t) = x.name = y.name 
 
 let is_runtime_package (x : t) = 
@@ -112,16 +120,10 @@ let empty : t =
     module_systems =  []
   }
 
-let from_name (name : string) =
-  if name = runtime_package_name then 
-    {
-      name = Pkg_runtime ; module_systems = [] 
-    }
-  else 
-    {
-      name = Pkg_normal name  ;
-      module_systems = [] 
-    }
+let from_name (name : string) : t = {
+  name = Pkg_normal name  ;
+  module_systems = [] 
+}
 
 let is_empty  (x : t) =
   x.name = Pkg_empty
@@ -156,7 +158,7 @@ let dump_package_name fmt (x : package_name) =
   match x with 
   | Pkg_empty -> Format.fprintf fmt "@empty_pkg@"
   | Pkg_normal s -> Format.pp_print_string fmt s 
-  | Pkg_runtime -> Format.pp_print_string fmt runtime_package_name
+  | Pkg_runtime -> Format.pp_print_string fmt "@runtime"
 
 let dump_packages_info 
     (fmt : Format.formatter) 
@@ -208,7 +210,7 @@ let query_package_infos
         compatible k.module_system  module_system)  with
     | Some k -> 
       let rel_path = k.path in 
-      let pkg_rel_path = runtime_package_name // rel_path in 
+      let pkg_rel_path = !Bs_version.package_name // rel_path in 
       Package_found 
         { 
           rel_path ;
@@ -221,7 +223,8 @@ let query_package_infos
 
 let get_js_path 
     (x : t )
-    module_system 
+    (module_system : module_system) 
+    : string
   = 
   match Ext_list.find_first x.module_systems (fun k -> 
       compatible k.module_system  module_system) with
diff --git a/jscomp/core/js_packages_info.mli b/jscomp/core/js_packages_info.mli
index 836054197b..36ed0ce24e 100644
--- a/jscomp/core/js_packages_info.mli
+++ b/jscomp/core/js_packages_info.mli
@@ -47,6 +47,9 @@ type package_info = {
 type t 
 
 val runtime_package_specs : t 
+
+val runtime_test_package_specs : t  
+
 val is_runtime_package:
   t ->
   bool
diff --git a/jscomp/core/js_packages_state.ml b/jscomp/core/js_packages_state.ml
index 19e72d7f11..38c9f2f447 100644
--- a/jscomp/core/js_packages_state.ml
+++ b/jscomp/core/js_packages_state.ml
@@ -33,6 +33,11 @@ let set_package_name name =
   else
     Bsc_args.bad_arg "duplicated flag for -bs-package-name"
 
+let make_runtime () : unit = 
+  packages_info :=  Js_packages_info.runtime_package_specs
+
+let make_runtime_test () : unit = 
+  packages_info := Js_packages_info.runtime_test_package_specs  
 let set_package_map module_name = 
     (* set_package_name name ; 
     let module_name = Ext_namespace.namespace_of_package_name name  in  *)
diff --git a/jscomp/core/js_packages_state.mli b/jscomp/core/js_packages_state.mli
index 38b08d5faa..a73012be76 100644
--- a/jscomp/core/js_packages_state.mli
+++ b/jscomp/core/js_packages_state.mli
@@ -26,6 +26,11 @@
 
 val set_package_name : string -> unit 
 
+val make_runtime:
+  unit -> unit
+
+val make_runtime_test:   
+  unit -> unit
 val set_package_map : string -> unit 
 
 val get_packages_info : 
diff --git a/jscomp/main/js_main.ml b/jscomp/main/js_main.ml
index 8fa2e11483..075b401397 100644
--- a/jscomp/main/js_main.ml
+++ b/jscomp/main/js_main.ml
@@ -443,7 +443,11 @@ let buckle_script_flags : (string * Bsc_args.spec * string) array =
     "<list>  Enable or disable error status for warnings according\n\
          to <list>.  See option -w for the syntax of <list>.\n\
          Default setting is " ^ Bsc_warnings.defaults_warn_error;    
-  
+    "-make-runtime", unit_call Js_packages_state.make_runtime,
+    "*internal* make runtime library";  
+    "-make-runtime-test", unit_call Js_packages_state.make_runtime_test,
+    "*internal* make runtime test library";  
+
   |]
 
 
diff --git a/jscomp/others/release.ninja b/jscomp/others/release.ninja
index 668d646cad..afbc249077 100644
--- a/jscomp/others/release.ninja
+++ b/jscomp/others/release.ninja
@@ -1,5 +1,5 @@
 
-bsc_flags = -no-keep-locs -no-alias-deps -bs-no-version-header -bs-no-check-div-by-zero -nostdlib  -bs-cross-module-opt -bs-package-name bs-platform -bs-package-output commonjs:lib/js  -bs-package-output es6:lib/es6:.mjs   -nopervasives  -unsafe  -w +50 -warn-error A  -open Bs_stdlib_mini -I ./runtime
+bsc_flags = -no-keep-locs -no-alias-deps -bs-no-version-header -bs-no-check-div-by-zero -nostdlib  -bs-cross-module-opt -make-runtime   -nopervasives  -unsafe  -w +50 -warn-error A  -open Bs_stdlib_mini -I ./runtime
 
 rule cc
     command = $bsc -bs-cmi -bs-cmj $bsc_flags   -I others  $in
diff --git a/jscomp/runtime/release.ninja b/jscomp/runtime/release.ninja
index 517d4a8db1..f7aedeca3d 100644
--- a/jscomp/runtime/release.ninja
+++ b/jscomp/runtime/release.ninja
@@ -1,5 +1,5 @@
 
-bsc_no_open_flags =  -no-keep-locs -no-alias-deps -bs-no-version-header -bs-no-check-div-by-zero -nostdlib  -bs-cross-module-opt -bs-package-name bs-platform -bs-package-output commonjs:lib/js  -bs-package-output es6:lib/es6:.mjs  -nopervasives  -unsafe -w +50 -warn-error A
+bsc_no_open_flags =  -no-keep-locs -no-alias-deps -bs-no-version-header -bs-no-check-div-by-zero -nostdlib  -bs-cross-module-opt -make-runtime  -nopervasives  -unsafe -w +50 -warn-error A
 bsc_flags = $bsc_no_open_flags -open Bs_stdlib_mini
 
 rule cc
diff --git a/jscomp/stdlib-406/release.ninja b/jscomp/stdlib-406/release.ninja
index c201aaf1be..a771eab578 100644
--- a/jscomp/stdlib-406/release.ninja
+++ b/jscomp/stdlib-406/release.ninja
@@ -1,5 +1,5 @@
 
-bsc_flags = -no-keep-locs -no-alias-deps -bs-no-version-header -bs-no-check-div-by-zero -nostdlib  -bs-cross-module-opt -bs-package-name bs-platform -bs-package-output commonjs:lib/js  -bs-package-output es6:lib/es6:.mjs   -w -9-3-106 -warn-error A  -I runtime  -I others
+bsc_flags = -no-keep-locs -no-alias-deps -bs-no-version-header -bs-no-check-div-by-zero -nostdlib  -bs-cross-module-opt -make-runtime    -w -9-3-106 -warn-error A  -I runtime  -I others
 
 rule cc
     command = $bsc -bs-cmi -bs-cmj $bsc_flags   -I stdlib-406  $in
diff --git a/jscomp/test/build.ninja b/jscomp/test/build.ninja
index 83e7a6eb9f..a83c8a2c41 100644
--- a/jscomp/test/build.ninja
+++ b/jscomp/test/build.ninja
@@ -1,5 +1,5 @@
 
-bsc_flags = -bs-no-version-header  -bs-cross-module-opt -bs-package-name bs-platform -bs-package-output commonjs:jscomp/test  -w -3-6-26-27-29-30-32..40-44-45-52-60-9-106+104 -warn-error A  -I runtime -I $stdlib -I others
+bsc_flags = -bs-no-version-header  -bs-cross-module-opt -make-runtime-test -bs-package-output commonjs:jscomp/test  -w -3-6-26-27-29-30-32..40-44-45-52-60-9-106+104 -warn-error A  -I runtime -I $stdlib -I others
 
 rule cc
     command = $bsc -bs-cmi -bs-cmj $bsc_flags   -I test  $in
diff --git a/lib/4.06.1/bsb.ml b/lib/4.06.1/bsb.ml
index d3816a66bb..f25c7453c6 100644
--- a/lib/4.06.1/bsb.ml
+++ b/lib/4.06.1/bsb.ml
@@ -28,7 +28,7 @@ val version : string
 
 val header : string 
 
-val package_name : string
+val package_name : string ref
 end = struct
 #1 "bs_version.ml"
 
@@ -55,10 +55,10 @@ end = struct
  * You should have received a copy of the GNU Lesser General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *)    
-let version = "8.4.0"
+let version = "8.5.0"
 let header = 
    "// Generated by ReScript, PLEASE EDIT WITH CARE"  
-let package_name = "bs-platform"   
+let package_name = ref "bs-platform"   
     
 end
 module Ext_array : sig 
@@ -6500,12 +6500,12 @@ let print (fmt : Format.formatter) (x : error) =
     | None -> Ext_string.empty
     | Some x -> " in " ^ x in
     let name = Bsb_pkg_types.to_string name in 
-    if Ext_string.equal name Bs_version.package_name then
+    if Ext_string.equal name !Bs_version.package_name then
       Format.fprintf fmt
       "File \"bsconfig.json\", line 1\n\
-       @{<error>Error:@} package @{<error>bs-platform@} is not found %s\n\
+       @{<error>Error:@} package @{<error>%s@} is not found %s\n\
        It's the basic, required package. If you have it installed globally,\n\
-       Please run `npm link bs-platform` to make it available" in_json
+       Please run `npm link bs-platform` to make it available" name in_json
     else
       Format.fprintf fmt
         "File \"bsconfig.json\", line 1\n\
@@ -11054,7 +11054,7 @@ end = struct
 
 (* let get_list_string = Bsb_build_util.get_list_string *)
 let (//) = Ext_path.combine
-let current_package : Bsb_pkg_types.t = Global Bs_version.package_name
+
 let resolve_package cwd  package_name = 
   let x =  Bsb_pkg.resolve_bs_package ~cwd package_name  in
   {
@@ -11142,6 +11142,7 @@ let check_stdlib (map : json_map) cwd (*built_in_package*) =
   | None 
   | Some _ ->
     begin
+      let current_package : Bsb_pkg_types.t = Global !Bs_version.package_name in  
       if Sys.getenv_opt "RES_SKIP_STDLIB_CHECK" = None then begin 
         let stdlib_path = 
           Bsb_pkg.resolve_bs_package ~cwd current_package in 
diff --git a/lib/4.06.1/unstable/js_compiler.ml b/lib/4.06.1/unstable/js_compiler.ml
index 2ba982e65b..730c8a208f 100644
--- a/lib/4.06.1/unstable/js_compiler.ml
+++ b/lib/4.06.1/unstable/js_compiler.ml
@@ -18090,7 +18090,7 @@ val version : string
 
 val header : string 
 
-val package_name : string
+val package_name : string ref
 end = struct
 #1 "bs_version.ml"
 
@@ -18117,10 +18117,10 @@ end = struct
  * You should have received a copy of the GNU Lesser General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *)    
-let version = "8.4.0"
+let version = "8.5.0"
 let header = 
    "// Generated by ReScript, PLEASE EDIT WITH CARE"  
-let package_name = "bs-platform"   
+let package_name = ref "bs-platform"   
     
 end
 module Bsc_warnings
@@ -92118,6 +92118,9 @@ type package_info = {
 type t 
 
 val runtime_package_specs : t 
+
+val runtime_test_package_specs : t  
+
 val is_runtime_package:
   t ->
   bool
@@ -92239,7 +92242,7 @@ type package_name  =
 
 
 
-let runtime_package_name = "bs-platform"
+
 
 
 let (//) = Filename.concat    
@@ -92253,7 +92256,7 @@ let runtime_dir_of_module_system (ms : module_system ) =
 let runtime_package_path 
     (ms : module_system) 
     js_file =        
-  runtime_package_name // "lib" // runtime_dir_of_module_system ms // js_file
+  !Bs_version.package_name // "lib" // runtime_dir_of_module_system ms // js_file
 
 
 type t =
@@ -92269,6 +92272,14 @@ let runtime_package_specs : t = {
     {module_system = NodeJS; path = "lib/js"; suffix = Js};
   ]
 }   
+
+(**
+  populated by the command line
+*)
+let runtime_test_package_specs : t = {
+  name = Pkg_runtime; 
+  module_systems = []
+}
 let same_package_by_name (x : t) (y : t) = x.name = y.name 
 
 let is_runtime_package (x : t) = 
@@ -92295,16 +92306,10 @@ let empty : t =
     module_systems =  []
   }
 
-let from_name (name : string) =
-  if name = runtime_package_name then 
-    {
-      name = Pkg_runtime ; module_systems = [] 
-    }
-  else 
-    {
-      name = Pkg_normal name  ;
-      module_systems = [] 
-    }
+let from_name (name : string) : t = {
+  name = Pkg_normal name  ;
+  module_systems = [] 
+}
 
 let is_empty  (x : t) =
   x.name = Pkg_empty
@@ -92339,7 +92344,7 @@ let dump_package_name fmt (x : package_name) =
   match x with 
   | Pkg_empty -> Format.fprintf fmt "@empty_pkg@"
   | Pkg_normal s -> Format.pp_print_string fmt s 
-  | Pkg_runtime -> Format.pp_print_string fmt runtime_package_name
+  | Pkg_runtime -> Format.pp_print_string fmt "@runtime"
 
 let dump_packages_info 
     (fmt : Format.formatter) 
@@ -92391,7 +92396,7 @@ let query_package_infos
         compatible k.module_system  module_system)  with
     | Some k -> 
       let rel_path = k.path in 
-      let pkg_rel_path = runtime_package_name // rel_path in 
+      let pkg_rel_path = !Bs_version.package_name // rel_path in 
       Package_found 
         { 
           rel_path ;
@@ -92404,7 +92409,8 @@ let query_package_infos
 
 let get_js_path 
     (x : t )
-    module_system 
+    (module_system : module_system) 
+    : string
   = 
   match Ext_list.find_first x.module_systems (fun k -> 
       compatible k.module_system  module_system) with
@@ -92499,6 +92505,11 @@ module Js_packages_state : sig
 
 val set_package_name : string -> unit 
 
+val make_runtime:
+  unit -> unit
+
+val make_runtime_test:   
+  unit -> unit
 val set_package_map : string -> unit 
 
 val get_packages_info : 
@@ -92543,6 +92554,11 @@ let set_package_name name =
   else
     Bsc_args.bad_arg "duplicated flag for -bs-package-name"
 
+let make_runtime () : unit = 
+  packages_info :=  Js_packages_info.runtime_package_specs
+
+let make_runtime_test () : unit = 
+  packages_info := Js_packages_info.runtime_test_package_specs  
 let set_package_map module_name = 
     (* set_package_name name ; 
     let module_name = Ext_namespace.namespace_of_package_name name  in  *)
@@ -98591,6 +98607,7 @@ let fix_path_for_windows : string -> string =
   else fun s -> s 
 
 
+(* dependency is runtime module *)  
 let get_runtime_module_path 
     (dep_module_id : Lam_module_ident.t) 
     (current_package_info : Js_packages_info.t)
diff --git a/lib/4.06.1/unstable/js_refmt_compiler.ml b/lib/4.06.1/unstable/js_refmt_compiler.ml
index 460aa368ab..5d7c1e908d 100644
--- a/lib/4.06.1/unstable/js_refmt_compiler.ml
+++ b/lib/4.06.1/unstable/js_refmt_compiler.ml
@@ -18090,7 +18090,7 @@ val version : string
 
 val header : string 
 
-val package_name : string
+val package_name : string ref
 end = struct
 #1 "bs_version.ml"
 
@@ -18117,10 +18117,10 @@ end = struct
  * You should have received a copy of the GNU Lesser General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *)    
-let version = "8.4.0"
+let version = "8.5.0"
 let header = 
    "// Generated by ReScript, PLEASE EDIT WITH CARE"  
-let package_name = "bs-platform"   
+let package_name = ref "bs-platform"   
     
 end
 module Bsc_warnings
@@ -92118,6 +92118,9 @@ type package_info = {
 type t 
 
 val runtime_package_specs : t 
+
+val runtime_test_package_specs : t  
+
 val is_runtime_package:
   t ->
   bool
@@ -92239,7 +92242,7 @@ type package_name  =
 
 
 
-let runtime_package_name = "bs-platform"
+
 
 
 let (//) = Filename.concat    
@@ -92253,7 +92256,7 @@ let runtime_dir_of_module_system (ms : module_system ) =
 let runtime_package_path 
     (ms : module_system) 
     js_file =        
-  runtime_package_name // "lib" // runtime_dir_of_module_system ms // js_file
+  !Bs_version.package_name // "lib" // runtime_dir_of_module_system ms // js_file
 
 
 type t =
@@ -92269,6 +92272,14 @@ let runtime_package_specs : t = {
     {module_system = NodeJS; path = "lib/js"; suffix = Js};
   ]
 }   
+
+(**
+  populated by the command line
+*)
+let runtime_test_package_specs : t = {
+  name = Pkg_runtime; 
+  module_systems = []
+}
 let same_package_by_name (x : t) (y : t) = x.name = y.name 
 
 let is_runtime_package (x : t) = 
@@ -92295,16 +92306,10 @@ let empty : t =
     module_systems =  []
   }
 
-let from_name (name : string) =
-  if name = runtime_package_name then 
-    {
-      name = Pkg_runtime ; module_systems = [] 
-    }
-  else 
-    {
-      name = Pkg_normal name  ;
-      module_systems = [] 
-    }
+let from_name (name : string) : t = {
+  name = Pkg_normal name  ;
+  module_systems = [] 
+}
 
 let is_empty  (x : t) =
   x.name = Pkg_empty
@@ -92339,7 +92344,7 @@ let dump_package_name fmt (x : package_name) =
   match x with 
   | Pkg_empty -> Format.fprintf fmt "@empty_pkg@"
   | Pkg_normal s -> Format.pp_print_string fmt s 
-  | Pkg_runtime -> Format.pp_print_string fmt runtime_package_name
+  | Pkg_runtime -> Format.pp_print_string fmt "@runtime"
 
 let dump_packages_info 
     (fmt : Format.formatter) 
@@ -92391,7 +92396,7 @@ let query_package_infos
         compatible k.module_system  module_system)  with
     | Some k -> 
       let rel_path = k.path in 
-      let pkg_rel_path = runtime_package_name // rel_path in 
+      let pkg_rel_path = !Bs_version.package_name // rel_path in 
       Package_found 
         { 
           rel_path ;
@@ -92404,7 +92409,8 @@ let query_package_infos
 
 let get_js_path 
     (x : t )
-    module_system 
+    (module_system : module_system) 
+    : string
   = 
   match Ext_list.find_first x.module_systems (fun k -> 
       compatible k.module_system  module_system) with
@@ -92499,6 +92505,11 @@ module Js_packages_state : sig
 
 val set_package_name : string -> unit 
 
+val make_runtime:
+  unit -> unit
+
+val make_runtime_test:   
+  unit -> unit
 val set_package_map : string -> unit 
 
 val get_packages_info : 
@@ -92543,6 +92554,11 @@ let set_package_name name =
   else
     Bsc_args.bad_arg "duplicated flag for -bs-package-name"
 
+let make_runtime () : unit = 
+  packages_info :=  Js_packages_info.runtime_package_specs
+
+let make_runtime_test () : unit = 
+  packages_info := Js_packages_info.runtime_test_package_specs  
 let set_package_map module_name = 
     (* set_package_name name ; 
     let module_name = Ext_namespace.namespace_of_package_name name  in  *)
@@ -98591,6 +98607,7 @@ let fix_path_for_windows : string -> string =
   else fun s -> s 
 
 
+(* dependency is runtime module *)  
 let get_runtime_module_path 
     (dep_module_id : Lam_module_ident.t) 
     (current_package_info : Js_packages_info.t)
diff --git a/lib/4.06.1/whole_compiler.ml b/lib/4.06.1/whole_compiler.ml
index f12dad3e2a..48d268230a 100644
--- a/lib/4.06.1/whole_compiler.ml
+++ b/lib/4.06.1/whole_compiler.ml
@@ -304574,7 +304574,7 @@ val version : string
 
 val header : string 
 
-val package_name : string
+val package_name : string ref
 end = struct
 #1 "bs_version.ml"
 
@@ -304601,10 +304601,10 @@ end = struct
  * You should have received a copy of the GNU Lesser General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *)    
-let version = "8.4.0"
+let version = "8.5.0"
 let header = 
    "// Generated by ReScript, PLEASE EDIT WITH CARE"  
-let package_name = "bs-platform"   
+let package_name = ref "bs-platform"   
     
 end
 module Bsc_warnings
@@ -370433,6 +370433,9 @@ type package_info = {
 type t 
 
 val runtime_package_specs : t 
+
+val runtime_test_package_specs : t  
+
 val is_runtime_package:
   t ->
   bool
@@ -370554,7 +370557,7 @@ type package_name  =
 
 
 
-let runtime_package_name = "bs-platform"
+
 
 
 let (//) = Filename.concat    
@@ -370568,7 +370571,7 @@ let runtime_dir_of_module_system (ms : module_system ) =
 let runtime_package_path 
     (ms : module_system) 
     js_file =        
-  runtime_package_name // "lib" // runtime_dir_of_module_system ms // js_file
+  !Bs_version.package_name // "lib" // runtime_dir_of_module_system ms // js_file
 
 
 type t =
@@ -370584,6 +370587,14 @@ let runtime_package_specs : t = {
     {module_system = NodeJS; path = "lib/js"; suffix = Js};
   ]
 }   
+
+(**
+  populated by the command line
+*)
+let runtime_test_package_specs : t = {
+  name = Pkg_runtime; 
+  module_systems = []
+}
 let same_package_by_name (x : t) (y : t) = x.name = y.name 
 
 let is_runtime_package (x : t) = 
@@ -370610,16 +370621,10 @@ let empty : t =
     module_systems =  []
   }
 
-let from_name (name : string) =
-  if name = runtime_package_name then 
-    {
-      name = Pkg_runtime ; module_systems = [] 
-    }
-  else 
-    {
-      name = Pkg_normal name  ;
-      module_systems = [] 
-    }
+let from_name (name : string) : t = {
+  name = Pkg_normal name  ;
+  module_systems = [] 
+}
 
 let is_empty  (x : t) =
   x.name = Pkg_empty
@@ -370654,7 +370659,7 @@ let dump_package_name fmt (x : package_name) =
   match x with 
   | Pkg_empty -> Format.fprintf fmt "@empty_pkg@"
   | Pkg_normal s -> Format.pp_print_string fmt s 
-  | Pkg_runtime -> Format.pp_print_string fmt runtime_package_name
+  | Pkg_runtime -> Format.pp_print_string fmt "@runtime"
 
 let dump_packages_info 
     (fmt : Format.formatter) 
@@ -370706,7 +370711,7 @@ let query_package_infos
         compatible k.module_system  module_system)  with
     | Some k -> 
       let rel_path = k.path in 
-      let pkg_rel_path = runtime_package_name // rel_path in 
+      let pkg_rel_path = !Bs_version.package_name // rel_path in 
       Package_found 
         { 
           rel_path ;
@@ -370719,7 +370724,8 @@ let query_package_infos
 
 let get_js_path 
     (x : t )
-    module_system 
+    (module_system : module_system) 
+    : string
   = 
   match Ext_list.find_first x.module_systems (fun k -> 
       compatible k.module_system  module_system) with
@@ -381040,6 +381046,11 @@ module Js_packages_state : sig
 
 val set_package_name : string -> unit 
 
+val make_runtime:
+  unit -> unit
+
+val make_runtime_test:   
+  unit -> unit
 val set_package_map : string -> unit 
 
 val get_packages_info : 
@@ -381084,6 +381095,11 @@ let set_package_name name =
   else
     Bsc_args.bad_arg "duplicated flag for -bs-package-name"
 
+let make_runtime () : unit = 
+  packages_info :=  Js_packages_info.runtime_package_specs
+
+let make_runtime_test () : unit = 
+  packages_info := Js_packages_info.runtime_test_package_specs  
 let set_package_map module_name = 
     (* set_package_name name ; 
     let module_name = Ext_namespace.namespace_of_package_name name  in  *)
@@ -381176,6 +381192,7 @@ let fix_path_for_windows : string -> string =
   else fun s -> s 
 
 
+(* dependency is runtime module *)  
 let get_runtime_module_path 
     (dep_module_id : Lam_module_ident.t) 
     (current_package_info : Js_packages_info.t)
@@ -436307,7 +436324,11 @@ let buckle_script_flags : (string * Bsc_args.spec * string) array =
     "<list>  Enable or disable error status for warnings according\n\
          to <list>.  See option -w for the syntax of <list>.\n\
          Default setting is " ^ Bsc_warnings.defaults_warn_error;    
-  
+    "-make-runtime", unit_call Js_packages_state.make_runtime,
+    "*internal* make runtime library";  
+    "-make-runtime-test", unit_call Js_packages_state.make_runtime_test,
+    "*internal* make runtime test library";  
+
   |]
 
 
diff --git a/package.json b/package.json
index 8c1c02fd2d..8b18b665a7 100644
--- a/package.json
+++ b/package.json
@@ -18,7 +18,7 @@
     "coverage": "nyc --timeout=3000 --reporter=html mocha jscomp/test/*test.js && open ./coverage/index.html"
   },
   "name": "bs-platform",
-  "version": "8.4.0",
+  "version": "8.5.0",
   "description": "ReScript compiler, OCaml standard libary by ReScript and its required runtime support",
   "repository": {
     "type": "git",
diff --git a/scripts/ninja.js b/scripts/ninja.js
index eab0d693e3..c99a1cece3 100755
--- a/scripts/ninja.js
+++ b/scripts/ninja.js
@@ -836,7 +836,7 @@ async function runtimeNinja(devmode = true) {
   var externalDeps = devmode ? [compilerTarget] : [];
   var ninjaOutput = devmode ? "build.ninja" : "release.ninja";
   var templateRuntimeRules = `
-bsc_no_open_flags =  ${commonBsFlags} -bs-cross-module-opt -bs-package-name bs-platform -bs-package-output commonjs:lib/js  -bs-package-output es6:lib/es6:.mjs  -nopervasives  -unsafe -w +50 -warn-error A
+bsc_no_open_flags =  ${commonBsFlags} -bs-cross-module-opt -make-runtime  -nopervasives  -unsafe -w +50 -warn-error A
 bsc_flags = $bsc_no_open_flags -open Bs_stdlib_mini
 ${ruleCC(ninjaCwd)}
 ${ninjaQuickBuidList([
@@ -931,7 +931,7 @@ async function othersNinja(devmode = true) {
   var ninjaCwd = "others";
 
   var templateOthersRules = `
-bsc_flags = ${commonBsFlags} -bs-cross-module-opt -bs-package-name bs-platform -bs-package-output commonjs:lib/js  -bs-package-output es6:lib/es6:.mjs   -nopervasives  -unsafe  -w +50 -warn-error A  -open Bs_stdlib_mini -I ./runtime
+bsc_flags = ${commonBsFlags} -bs-cross-module-opt -make-runtime   -nopervasives  -unsafe  -w +50 -warn-error A  -open Bs_stdlib_mini -I ./runtime
 ${ruleCC(ninjaCwd)}
 ${
   devmode
@@ -1056,7 +1056,7 @@ async function stdlibNinja(devmode = true) {
   // deprecations diabled due to string_of_float
   var warnings = "-w -9-3-106 -warn-error A";
   var templateStdlibRules = `
-${bsc_flags} = ${commonBsFlags} -bs-cross-module-opt -bs-package-name bs-platform -bs-package-output commonjs:lib/js  -bs-package-output es6:lib/es6:.mjs   ${warnings}  -I runtime  -I others
+${bsc_flags} = ${commonBsFlags} -bs-cross-module-opt -make-runtime    ${warnings}  -I runtime  -I others
 ${ruleCC(ninjaCwd)}
 ${ninjaQuickBuidList([
   [
@@ -1190,7 +1190,7 @@ async function testNinja() {
   var ninjaOutput = "build.ninja";
   var ninjaCwd = `test`;
   var templateTestRules = `
-bsc_flags = -bs-no-version-header  -bs-cross-module-opt -bs-package-name bs-platform -bs-package-output commonjs:jscomp/test  -w -3-6-26-27-29-30-32..40-44-45-52-60-9-106+104 -warn-error A  -I runtime -I $stdlib -I others
+bsc_flags = -bs-no-version-header  -bs-cross-module-opt -make-runtime-test -bs-package-output commonjs:jscomp/test  -w -3-6-26-27-29-30-32..40-44-45-52-60-9-106+104 -warn-error A  -I runtime -I $stdlib -I others
 ${ruleCC(ninjaCwd)}