From 5cae26e2208eba42e44bacbbe5843c12ad78e6d1 Mon Sep 17 00:00:00 2001
From: Frixuu <code@frixuu.fyi>
Date: Tue, 21 Apr 2026 23:44:39 +0200
Subject: [PATCH 01/16] Add `js.module` define

---
 src-json/define.json    |  8 ++++++++
 src/generators/genjs.ml | 15 +++++++++++++--
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/src-json/define.json b/src-json/define.json
index fbbbecd4b58..ab4d7c8200b 100644
--- a/src-json/define.json
+++ b/src-json/define.json
@@ -524,6 +524,14 @@
 		"doc": "Customizes the global object name.",
 		"platforms": ["js"]
 	},
+	{
+		"name": "JsModule",
+		"define": "js.module",
+		"doc": "Customizes the JS module output type. (default: iife)",
+		"platforms": ["js"],
+		"params": ["type: es | iife"],
+		"default": "iife"
+	},
 	{
 		"name": "JsUnflatten",
 		"define": "js-unflatten",
diff --git a/src/generators/genjs.ml b/src/generators/genjs.ml
index c7c1784a0ad..a65d46ac1da 100644
--- a/src/generators/genjs.ml
+++ b/src/generators/genjs.ml
@@ -24,6 +24,10 @@ open Error
 open Gctx
 open JsSourcemap
 
+type js_module_type = 
+	| Es
+	| Iife
+
 type ctx = {
 	com : Gctx.t;
 	buf : Rbuffer.t;
@@ -32,6 +36,7 @@ type ctx = {
 	smap : sourcemap option;
 	js_modern : bool;
 	js_flatten : bool;
+	js_module_type : js_module_type;
 	has_resolveClass : bool;
 	has_interface_check : bool;
 	es_version : int;
@@ -1616,6 +1621,11 @@ let alloc_ctx com es_version =
 		smap = smap;
 		js_modern = not (Gctx.defined com Define.JsClassic);
 		js_flatten = not (Gctx.defined com Define.JsUnflatten);
+		js_module_type = (match Gctx.defined_value_safe ~default:"iife" com Define.JsModule with
+			| "es" -> (if es_version >= 6 then Es else failwith "ES modules require targetting ES6 or higher")
+			| "iife" -> Iife
+			| _ -> failwith "Invalid `js.module` define. Use `es` or `iife`"
+		);
 		has_resolveClass = Gctx.has_feature com "Type.resolveClass";
 		has_interface_check = Gctx.has_feature com "js.Boot.__interfLoop";
 		es_version = es_version;
@@ -1833,7 +1843,7 @@ let generate js_gen com =
 		newline ctx
 	);
 
-	if ctx.js_modern then begin
+	if (ctx.js_modern && ctx.js_module_type = Iife) then begin
 		(* Wrap output in a closure *)
 		print ctx "(function (%s) { \"use strict\"" (String.concat ", " (List.map fst closureArgs));
 		newline ctx;
@@ -1955,7 +1965,8 @@ let generate js_gen com =
 	(match com.main.main_expr with
 	| None -> ()
 	| Some e -> gen_expr ctx e; newline ctx);
-	if ctx.js_modern then begin
+
+	if (ctx.js_modern && ctx.js_module_type = Iife) then begin
 		let closureArgs =
 			if has_feature ctx "js.Lib.global" || defined_global then
 				closureArgs

From 7e3d06188a60cdf24effc158dfc4bc30ac5e2a18 Mon Sep 17 00:00:00 2001
From: Frixuu <code@frixuu.fyi>
Date: Wed, 22 Apr 2026 02:54:54 +0200
Subject: [PATCH 02/16] Use `export` statements with classes and static methods

---
 src/generators/genjs.ml | 49 +++++++++++++++++++++++++++++++++++++----
 1 file changed, 45 insertions(+), 4 deletions(-)

diff --git a/src/generators/genjs.ml b/src/generators/genjs.ml
index a65d46ac1da..04b8330e1d7 100644
--- a/src/generators/genjs.ml
+++ b/src/generators/genjs.ml
@@ -1246,6 +1246,37 @@ let generate_class_es5 ctx c =
 	end;
 	flush ctx
 
+let tmp_var_counter = ref 0
+let export_tmp_name() = 
+	let name = Printf.sprintf "$hx_export_tmp_%d" !tmp_var_counter in
+	tmp_var_counter := !tmp_var_counter + 1;
+	name
+
+let generate_export_statement_es6 ctx expr ident =
+	if (ctx.js_module_type == Es) then
+		if not (ExtString.String.contains ident '.') then
+			(*
+				The lack of dots in ident typically means an explicit identifier (or no package).
+				Either way, assume the user knows what they're doing:
+				do not validate identifiers, do not check for name collisions
+			*)
+			print ctx "export const %s = %s;" ident expr
+		else begin
+			let tmp_name = export_tmp_name() in
+			let exported_name = if ctx.es_version >= 2022 then
+				(* Keyword: "arbitrary module namespace identifier names" *)
+				Printf.sprintf "\"%s\"" ident
+			else
+				(* Older versions need mangling *)
+				let parts = ExtString.String.nsplit ident "." in
+				String.concat "_" parts
+			in
+			print ctx "const %s = %s; export {%s as %s};" tmp_name expr tmp_name exported_name
+		end
+	else
+		print ctx "$hx_exports%s = %s;" (path_to_brackets ident) expr;
+	newline ctx
+
 let generate_class_es6 ctx c =
 	let cl_path = get_generated_class_path c in
 	let p = s_path ctx cl_path in
@@ -1316,16 +1347,15 @@ let generate_class_es6 ctx c =
 	spr ctx "}";
 	newline ctx;
 
-	List.iter (fun (path,name) ->
-		print ctx "$hx_exports%s = %s.%s;" (path_to_brackets path) p name;
-		newline ctx
+	List.iter (fun (path, name) ->
+		generate_export_statement_es6 ctx (Printf.sprintf "%s.%s" p name) path
 	) !exposed_static_methods;
 
 	List.iter (gen_class_static_field ctx c cl_path) nonmethod_statics;
 
 	let is_abstract_impl = is_abstract_impl c in
 
-	begin
+	if ctx.js_module_type = Iife then begin
 		let added = ref false in
 		if ctx.has_resolveClass && not is_abstract_impl then begin
 			added := true;
@@ -1336,6 +1366,12 @@ let generate_class_es6 ctx c =
 			spr ctx p;
 			newline ctx;
 		end;
+	end else begin
+		if ctx.has_resolveClass && not is_abstract_impl then begin
+			print ctx "$hxClasses[\"%s\"] = %s;" dotp p;
+			newline ctx;
+		end;
+		process_expose c.cl_meta (fun () -> dotp) (fun s -> generate_export_statement_es6 ctx p s);
 	end;
 
 	if not is_abstract_impl then begin
@@ -1849,6 +1885,11 @@ let generate js_gen com =
 		newline ctx;
 	end;
 
+	(* 
+		If necessary, generate objects for subpackages in the main exports object.
+		For example: `package foo; @:expose class Bar {}`
+		will generate `exports["foo"]["Bar"] = exports["foo"]["Bar"] || {};`.
+	*)
 	let rec print_obj f root = (
 		let path = root ^ (path_to_brackets f.os_name) in
 		print ctx "%s = %s || {}" path path;

From 9c9de726a50830cdf5f446e67b151721e080ec24 Mon Sep 17 00:00:00 2001
From: Frixuu <code@frixuu.fyi>
Date: Wed, 22 Apr 2026 12:53:20 +0200
Subject: [PATCH 03/16] Generate `export class` form if possible

---
 src/generators/genjs.ml | 39 +++++++++++++++++++++++++++++----------
 1 file changed, 29 insertions(+), 10 deletions(-)

diff --git a/src/generators/genjs.ml b/src/generators/genjs.ml
index 04b8330e1d7..6d34e2aafbf 100644
--- a/src/generators/genjs.ml
+++ b/src/generators/genjs.ml
@@ -1253,17 +1253,13 @@ let export_tmp_name() =
 	name
 
 let generate_export_statement_es6 ctx expr ident =
-	if (ctx.js_module_type == Es) then
-		if not (ExtString.String.contains ident '.') then
-			(*
-				The lack of dots in ident typically means an explicit identifier (or no package).
-				Either way, assume the user knows what they're doing:
-				do not validate identifiers, do not check for name collisions
-			*)
+	if ctx.js_module_type == Es then
+		let ident_contains_dots = ExtString.String.contains ident '.' in
+		if (not ident_contains_dots) && expr <> ident then
 			print ctx "export const %s = %s;" ident expr
 		else begin
 			let tmp_name = export_tmp_name() in
-			let exported_name = if ctx.es_version >= 2022 then
+			let exported_name = if ident_contains_dots && ctx.es_version >= 2022 then
 				(* Keyword: "arbitrary module namespace identifier names" *)
 				Printf.sprintf "\"%s\"" ident
 			else
@@ -1281,14 +1277,36 @@ let generate_class_es6 ctx c =
 	let cl_path = get_generated_class_path c in
 	let p = s_path ctx cl_path in
 	let dotp = dot_path cl_path in
+	let class_already_exported = ref false in 
 
 	let cls_name =
 		if not ctx.js_flatten && (fst cl_path) <> [] then begin
 			generate_package_create ctx cl_path;
 			print ctx "%s = " p;
 			Path.flat_path cl_path
-		end else
+		end else begin
+
+			if ctx.js_module_type = Es then begin
+				try
+					let (_, args, pos) = Meta.get Meta.Expose c.cl_meta in
+					match args with
+					| [EConst (String(s, _)), _] -> begin
+						if p = s then begin
+							print ctx "export ";
+							class_already_exported := true;
+						end
+					end
+					| [] -> begin
+						print ctx "export ";
+						class_already_exported := true;
+					end
+					| _ -> abort "Invalid @:expose parameters" pos
+				with Not_found ->
+					();
+			end;
+
 			p
+		end
 	in
 	print ctx "class %s" cls_name;
 
@@ -1371,7 +1389,8 @@ let generate_class_es6 ctx c =
 			print ctx "$hxClasses[\"%s\"] = %s;" dotp p;
 			newline ctx;
 		end;
-		process_expose c.cl_meta (fun () -> dotp) (fun s -> generate_export_statement_es6 ctx p s);
+		if not !class_already_exported then
+			process_expose c.cl_meta (fun () -> dotp) (fun s -> generate_export_statement_es6 ctx p s);
 	end;
 
 	if not is_abstract_impl then begin

From 862bcad89cc80b1b6575d0c4c4f4e3c81dd1ddc4 Mon Sep 17 00:00:00 2001
From: Frixuu <code@frixuu.fyi>
Date: Wed, 22 Apr 2026 14:29:54 +0200
Subject: [PATCH 04/16] Export static fields, module functions

---
 src/generators/genjs.ml | 115 ++++++++++++++++++++++++++--------------
 1 file changed, 74 insertions(+), 41 deletions(-)

diff --git a/src/generators/genjs.ml b/src/generators/genjs.ml
index 6d34e2aafbf..be3ea3b483f 100644
--- a/src/generators/genjs.ml
+++ b/src/generators/genjs.ml
@@ -1040,6 +1040,34 @@ let path_to_brackets path =
 	let parts = ExtString.String.nsplit path "." in
 	"[\"" ^ (String.concat "\"][\"" parts) ^ "\"]"
 
+let mangle_export_name_es6 ctx ident =
+	if ctx.es_version >= 2022 then
+		(* Keyword: "arbitrary module namespace identifier names" *)
+		Printf.sprintf "\"%s\"" ident
+	else
+		let parts = ExtString.String.nsplit ident "." in
+		String.concat "_" parts
+
+let tmp_var_counter = ref 0
+let export_tmp_name() = 
+	let name = Printf.sprintf "$hx_export_tmp_%d" !tmp_var_counter in
+	tmp_var_counter := !tmp_var_counter + 1;
+	name
+
+let generate_export_statement ctx expr ident =
+	if ctx.js_module_type == Es then
+		let ident_contains_dots = ExtString.String.contains ident '.' in
+		if (not ident_contains_dots) && expr <> ident then
+			print ctx "export const %s = %s;" ident expr
+		else begin
+			let tmp_name = export_tmp_name() in
+			let exported_name = if ident_contains_dots then mangle_export_name_es6 ctx ident else ident in
+			print ctx "const %s = %s; export {%s as %s};" tmp_name expr tmp_name exported_name
+		end
+	else
+		print ctx "$hx_exports%s = %s;" (path_to_brackets ident) expr;
+	newline ctx
+
 let gen_module_fields ctx m c fl =
 	List.iter (fun f ->
 		let name = module_field m f in
@@ -1053,14 +1081,25 @@ let gen_module_fields ctx m c fl =
 			match e.eexpr with
 			| TFunction fn ->
 				ctx.id_counter <- 0;
+
+				let already_exported = ref false in
+				let expose_fallback = module_field_expose_path m.m_path f in
+				if ctx.js_module_type = Es then
+					process_expose f.cf_meta (fun () -> expose_fallback) (fun s ->
+						if name = (mangle_export_name_es6 ctx s) then begin
+							print ctx "export ";
+							already_exported := true;
+						end
+					);
+
 				print ctx "function %s" name;
 				gen_function ~keyword:"" ctx fn e.epos;
 				ctx.separator <- false;
 				newline ctx;
-				process_expose f.cf_meta (fun () -> module_field_expose_path m.m_path f) (fun s ->
-					print ctx "$hx_exports%s = %s" (path_to_brackets s) name;
-					newline ctx
-				)
+				if not !already_exported then
+					process_expose f.cf_meta (fun () -> expose_fallback) (fun s ->
+						generate_export_statement ctx name s
+					)
 			| _ ->
 				ctx.statics <- (c,f,e) :: ctx.statics
 	) fl
@@ -1246,33 +1285,6 @@ let generate_class_es5 ctx c =
 	end;
 	flush ctx
 
-let tmp_var_counter = ref 0
-let export_tmp_name() = 
-	let name = Printf.sprintf "$hx_export_tmp_%d" !tmp_var_counter in
-	tmp_var_counter := !tmp_var_counter + 1;
-	name
-
-let generate_export_statement_es6 ctx expr ident =
-	if ctx.js_module_type == Es then
-		let ident_contains_dots = ExtString.String.contains ident '.' in
-		if (not ident_contains_dots) && expr <> ident then
-			print ctx "export const %s = %s;" ident expr
-		else begin
-			let tmp_name = export_tmp_name() in
-			let exported_name = if ident_contains_dots && ctx.es_version >= 2022 then
-				(* Keyword: "arbitrary module namespace identifier names" *)
-				Printf.sprintf "\"%s\"" ident
-			else
-				(* Older versions need mangling *)
-				let parts = ExtString.String.nsplit ident "." in
-				String.concat "_" parts
-			in
-			print ctx "const %s = %s; export {%s as %s};" tmp_name expr tmp_name exported_name
-		end
-	else
-		print ctx "$hx_exports%s = %s;" (path_to_brackets ident) expr;
-	newline ctx
-
 let generate_class_es6 ctx c =
 	let cl_path = get_generated_class_path c in
 	let p = s_path ctx cl_path in
@@ -1366,7 +1378,7 @@ let generate_class_es6 ctx c =
 	newline ctx;
 
 	List.iter (fun (path, name) ->
-		generate_export_statement_es6 ctx (Printf.sprintf "%s.%s" p name) path
+		generate_export_statement ctx (Printf.sprintf "%s.%s" p name) path
 	) !exposed_static_methods;
 
 	List.iter (gen_class_static_field ctx c cl_path) nonmethod_statics;
@@ -1390,7 +1402,7 @@ let generate_class_es6 ctx c =
 			newline ctx;
 		end;
 		if not !class_already_exported then
-			process_expose c.cl_meta (fun () -> dotp) (fun s -> generate_export_statement_es6 ctx p s);
+			process_expose c.cl_meta (fun () -> dotp) (fun s -> generate_export_statement ctx p s);
 	end;
 
 	if not is_abstract_impl then begin
@@ -1585,18 +1597,39 @@ let generate_enum ctx e =
 	flush ctx
 
 let generate_static ctx (c,f,e) =
-	begin
+	let already_exported = ref false in
 	match c.cl_kind with
 	| KModuleFields m ->
-		print ctx "var %s = " (module_field m f);
-		process_expose f.cf_meta (fun () -> module_field_expose_path m.m_path f) (fun s -> print ctx "$hx_exports%s = " (path_to_brackets s));
+		
+		let kwd = if ctx.js_module_type = Es then "let" else "var" in
+		let var_name = module_field m f in
+		let expose_fallback = module_field_expose_path m.m_path f in
+
+		if ctx.js_module_type = Es then
+			process_expose f.cf_meta (fun () -> expose_fallback) (fun s ->
+				if var_name = (mangle_export_name_es6 ctx s) then begin
+					print ctx "export ";
+					already_exported := true;
+				end
+			);
+
+		print ctx "%s %s = " kwd var_name;
+		gen_value ctx e;
+		newline ctx;
+
+		if not !already_exported then
+			process_expose f.cf_meta (fun () -> expose_fallback) (fun s ->
+				generate_export_statement ctx var_name s
+			)
 	| _ ->
 		let cl_path = get_generated_class_path c in
-		process_expose f.cf_meta (fun () -> (dot_path cl_path) ^ "." ^ f.cf_name) (fun s -> print ctx "$hx_exports%s = " (path_to_brackets s));
-		print ctx "%s%s = " (s_path ctx cl_path) (static_field ctx c f);
-	end;
-	gen_value ctx e;
-	newline ctx
+		let expr = Printf.sprintf "%s%s" (s_path ctx cl_path) (static_field ctx c f) in
+		print ctx "%s = " expr;
+		gen_value ctx e;
+		newline ctx;
+		process_expose f.cf_meta (fun () -> (dot_path cl_path) ^ "." ^ f.cf_name) (fun s ->
+			generate_export_statement ctx expr s
+		)
 
 let generate_require ctx path meta =
 	let _, args, mp = Meta.get Meta.JsRequire meta in

From d4123ecf5e808a576c1e21137e58bcc469f7cc5e Mon Sep 17 00:00:00 2001
From: Frixuu <code@frixuu.fyi>
Date: Wed, 22 Apr 2026 14:37:51 +0200
Subject: [PATCH 05/16] Export static class fields that are functions

---
 src/generators/genjs.ml | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/generators/genjs.ml b/src/generators/genjs.ml
index be3ea3b483f..f340008a6f4 100644
--- a/src/generators/genjs.ml
+++ b/src/generators/genjs.ml
@@ -1116,12 +1116,14 @@ let gen_class_static_field ctx c cl_path f =
 	| Some e ->
 		match e.eexpr with
 		| TFunction _ ->
-			let path = (s_path ctx cl_path) ^ (static_field ctx c f) in
 			ctx.id_counter <- 0;
+			let path = (s_path ctx cl_path) ^ (static_field ctx c f) in
 			print ctx "%s = " path;
-			process_expose f.cf_meta (fun () -> (dot_path cl_path) ^ "." ^ f.cf_name) (fun s -> print ctx "$hx_exports%s = " (path_to_brackets s));
 			gen_value ctx e;
 			newline ctx;
+			process_expose f.cf_meta (fun () -> (dot_path cl_path) ^ "." ^ f.cf_name) (fun s ->
+				generate_export_statement ctx path s
+			);
 		| _ ->
 			ctx.statics <- (c,f,e) :: ctx.statics
 

From 028e8e62c1028f9da424cd25333f304e8f732ad8 Mon Sep 17 00:00:00 2001
From: Frixuu <code@frixuu.fyi>
Date: Wed, 22 Apr 2026 14:41:04 +0200
Subject: [PATCH 06/16] Simplify class generation with `resolveClass` feature

---
 src/generators/genjs.ml | 24 ++++++------------------
 1 file changed, 6 insertions(+), 18 deletions(-)

diff --git a/src/generators/genjs.ml b/src/generators/genjs.ml
index f340008a6f4..b245d22fd30 100644
--- a/src/generators/genjs.ml
+++ b/src/generators/genjs.ml
@@ -1387,25 +1387,13 @@ let generate_class_es6 ctx c =
 
 	let is_abstract_impl = is_abstract_impl c in
 
-	if ctx.js_module_type = Iife then begin
-		let added = ref false in
-		if ctx.has_resolveClass && not is_abstract_impl then begin
-			added := true;
-			print ctx "$hxClasses[\"%s\"] = " dotp
-		end;
-		process_expose c.cl_meta (fun () -> dotp) (fun s -> added := true; print ctx "$hx_exports%s = " (path_to_brackets s));
-		if !added then begin
-			spr ctx p;
-			newline ctx;
-		end;
-	end else begin
-		if ctx.has_resolveClass && not is_abstract_impl then begin
-			print ctx "$hxClasses[\"%s\"] = %s;" dotp p;
-			newline ctx;
-		end;
-		if not !class_already_exported then
-			process_expose c.cl_meta (fun () -> dotp) (fun s -> generate_export_statement ctx p s);
+	if ctx.has_resolveClass && not is_abstract_impl then begin
+		print ctx "$hxClasses[\"%s\"] = %s;" dotp p;
+		newline ctx;
 	end;
+	
+	if not !class_already_exported then
+		process_expose c.cl_meta (fun () -> dotp) (fun s -> generate_export_statement ctx p s);
 
 	if not is_abstract_impl then begin
 		generate_class___name__ ctx cl_path;

From 4a29f30f3f95642baf1db299813d5b51f764ced0 Mon Sep 17 00:00:00 2001
From: Frixuu <code@frixuu.fyi>
Date: Wed, 22 Apr 2026 14:46:56 +0200
Subject: [PATCH 07/16] Don't prepopulate `$hx_exports` when using ES modules

---
 src/generators/genjs.ml | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/generators/genjs.ml b/src/generators/genjs.ml
index b245d22fd30..d3269c0b51d 100644
--- a/src/generators/genjs.ml
+++ b/src/generators/genjs.ml
@@ -1940,7 +1940,9 @@ let generate js_gen com =
 		concat ctx ";" (fun g -> print_obj g path) f.os_fields
 	)
 	in
-	List.iter (fun f -> print_obj f "$hx_exports") exposedObject.os_fields;
+
+	if ctx.js_module_type <> Es then
+		List.iter (fun f -> print_obj f "$hx_exports") exposedObject.os_fields;
 
 	List.iter (fun file ->
 		match file with

From 506d4f902fdaf1fb87566b643fc417b52ffbe0c8 Mon Sep 17 00:00:00 2001
From: Frixuu <code@frixuu.fyi>
Date: Wed, 22 Apr 2026 15:28:36 +0200
Subject: [PATCH 08/16] Generate `$global` in ES modules if `globalThis` is
 unavailable

---
 src/generators/genjs.ml | 9 ++++++---
 std/js/Lib.hx           | 6 +++++-
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/src/generators/genjs.ml b/src/generators/genjs.ml
index d3269c0b51d..d4e284f6263 100644
--- a/src/generators/genjs.ml
+++ b/src/generators/genjs.ml
@@ -1391,7 +1391,7 @@ let generate_class_es6 ctx c =
 		print ctx "$hxClasses[\"%s\"] = %s;" dotp p;
 		newline ctx;
 	end;
-	
+
 	if not !class_already_exported then
 		process_expose c.cl_meta (fun () -> dotp) (fun s -> generate_export_statement ctx p s);
 
@@ -1902,7 +1902,7 @@ let generate js_gen com =
 
 	let var_global = (
 		"$global",
-		typeof_join (if defined_global then [defined_global_value] else ["window"; "global"; "self"; "this"])
+		typeof_join (if defined_global then [defined_global_value] else ["globalThis"; "window"; "global"; "self"; "this"])
 	) in
 
 	let closureArgs = [var_global] in
@@ -1954,7 +1954,10 @@ let generate js_gen com =
 	) include_files;
 
 	if (not ctx.js_modern) then
-		print ctx "var %s = %s;\n" (fst var_global) (snd var_global);
+		print ctx "var %s = %s;\n" (fst var_global) (snd var_global)
+	else if ctx.js_module_type = Es then
+		if has_feature ctx "js.Lib.global" || has_feature ctx "use.$bind" || has_feature ctx "$global.$haxeUID" then
+			print ctx "const %s = %s;\n" (fst var_global) (snd var_global);
 
 	let enums_as_objects = not (Gctx.defined com Define.JsEnumsAsArrays) in
 
diff --git a/std/js/Lib.hx b/std/js/Lib.hx
index 43722b4e5a5..4b966d99bbc 100644
--- a/std/js/Lib.hx
+++ b/std/js/Lib.hx
@@ -123,12 +123,16 @@ class Lib {
 		An alias of the JS "global" object.
 
 		Concretely, it is set as the first defined value in the list of
-		`window`, `global`, `self`, and `this` in the top-level of the compiled output.
+		`globalThis`, `window`, `global`, `self`, and `this` in the top-level of the compiled output.
 	**/
 	public static var global(get, never):Dynamic;
 
 	extern static inline function get_global():Dynamic {
+		#if ((js_es >= 2020) && (js.module == "es") && !js_global)
+		return js.Syntax.code("globalThis");
+		#else
 		return untyped __define_feature__("js.Lib.global", js.Syntax.code("$global")); // $global is generated by the compiler
+		#end
 	}
 
 	/**

From 3a981f39551d2615a7365aed6b270c7f535f9de6 Mon Sep 17 00:00:00 2001
From: Frixuu <code@frixuu.fyi>
Date: Thu, 23 Apr 2026 01:12:17 +0200
Subject: [PATCH 09/16] Deprecate `-D js-classic` in favor of `-D
 js-module=classic`

---
 src-json/define.json    |  6 ++---
 src/generators/genjs.ml | 58 +++++++++++++++++++++++------------------
 2 files changed, 35 insertions(+), 29 deletions(-)

diff --git a/src-json/define.json b/src-json/define.json
index ab4d7c8200b..b63a47a1344 100644
--- a/src-json/define.json
+++ b/src-json/define.json
@@ -502,7 +502,8 @@
 		"name": "JsClassic",
 		"define": "js-classic",
 		"doc": "Don't use a function wrapper and strict mode in JS output.",
-		"platforms": ["js"]
+		"platforms": ["js"],
+		"deprecated": "Use `-D js.module=classic` instead."
 	},
 	{
 		"name": "JsEs",
@@ -529,8 +530,7 @@
 		"define": "js.module",
 		"doc": "Customizes the JS module output type. (default: iife)",
 		"platforms": ["js"],
-		"params": ["type: es | iife"],
-		"default": "iife"
+		"params": ["type: es | iife | classic"]
 	},
 	{
 		"name": "JsUnflatten",
diff --git a/src/generators/genjs.ml b/src/generators/genjs.ml
index d4e284f6263..b8570f0484c 100644
--- a/src/generators/genjs.ml
+++ b/src/generators/genjs.ml
@@ -24,9 +24,10 @@ open Error
 open Gctx
 open JsSourcemap
 
-type js_module_type = 
+type js_module_type =
 	| Es
 	| Iife
+	| Classic
 
 type ctx = {
 	com : Gctx.t;
@@ -34,7 +35,6 @@ type ctx = {
 	mutable chan : out_channel option;
 	packages : (string list,unit) Hashtbl.t;
 	smap : sourcemap option;
-	js_modern : bool;
 	js_flatten : bool;
 	js_module_type : js_module_type;
 	has_resolveClass : bool;
@@ -1010,16 +1010,14 @@ let generate_package_create ctx (p,_) =
 			Hashtbl.add ctx.packages (p :: acc) ();
 			(match acc with
 			| [] ->
-				if ctx.js_modern then
-					print ctx "var %s = {}" p
-				else
-					print ctx "var %s = %s || {}" p p
+				(match ctx.js_module_type with
+				| Classic -> print ctx "var %s = %s || {}" p p
+				| _ ->       print ctx "var %s = {}" p)
 			| _ ->
 				let p = String.concat "." (List.rev acc) ^ (field p) in
-				if ctx.js_modern then
-					print ctx "%s = {}" p
-				else
-					print ctx "if(!%s) %s = {}" p p
+				(match ctx.js_module_type with
+				| Classic -> print ctx "if(!%s) %s = {}" p p
+				| _ ->       print ctx "%s = {}" p)
 			);
 			ctx.separator <- true;
 			newline ctx;
@@ -1188,7 +1186,7 @@ let generate_class_es5 ctx c =
 
 	(* Do not add to $hxClasses on same line as declaration to make sure not to trip js debugger *)
 	(* when it tries to get a string representation of a class. Will be added below *)
-	if ctx.com.debug || ctx.js_modern || not added_to_hxClasses then
+	if ctx.com.debug || ctx.js_module_type <> Classic || not added_to_hxClasses then
 		print ctx "%s = " p
 	else
 		print ctx "%s = $hxClasses[\"%s\"] = " p dotp;
@@ -1208,7 +1206,7 @@ let generate_class_es5 ctx c =
 
 	newline ctx;
 
-	if (ctx.js_modern || ctx.com.debug) && added_to_hxClasses then begin
+	if (ctx.js_module_type <> Classic || ctx.com.debug) && added_to_hxClasses then begin
 		print ctx "$hxClasses[\"%s\"] = %s" dotp p;
 		newline ctx;
 	end;
@@ -1697,13 +1695,16 @@ let alloc_ctx com es_version =
 		chan = None;
 		packages = Hashtbl.create 0;
 		smap = smap;
-		js_modern = not (Gctx.defined com Define.JsClassic);
 		js_flatten = not (Gctx.defined com Define.JsUnflatten);
-		js_module_type = (match Gctx.defined_value_safe ~default:"iife" com Define.JsModule with
-			| "es" -> (if es_version >= 6 then Es else failwith "ES modules require targetting ES6 or higher")
-			| "iife" -> Iife
-			| _ -> failwith "Invalid `js.module` define. Use `es` or `iife`"
-		);
+		js_module_type = begin
+			let fallback = if (Gctx.defined com Define.JsClassic) then "classic" else "iife" in
+			(match Gctx.defined_value_safe ~default:fallback com Define.JsModule with
+				| "es" -> (if es_version >= 6 then Es else failwith "ES modules require targetting ES6 or higher")
+				| "iife" -> Iife
+				| "classic" -> Classic
+				| _ -> failwith "Invalid `js.module` define. Use `es`, `iife`, or `classic`"
+			)	
+		end;
 		has_resolveClass = Gctx.has_feature com "Type.resolveClass";
 		has_interface_check = Gctx.has_feature com "js.Boot.__interfLoop";
 		es_version = es_version;
@@ -1915,13 +1916,13 @@ let generate js_gen com =
 		(* Add node globals to pseudo-keywords, so they are not shadowed by local vars *)
 		List.iter (fun s -> Hashtbl.replace kwds2 s ()) [ "global"; "process"; "__filename"; "__dirname"; "module" ];
 
-	if (anyExposed && ((Gctx.defined com Define.ShallowExpose) || not ctx.js_modern)) then (
+	if (anyExposed && ((Gctx.defined com Define.ShallowExpose) || ctx.js_module_type = Classic)) then (
 		print ctx "var %s = %s" (fst var_exports) (snd var_exports);
 		ctx.separator <- true;
 		newline ctx
 	);
 
-	if (ctx.js_modern && ctx.js_module_type = Iife) then begin
+	if (ctx.js_module_type = Iife) then begin
 		(* Wrap output in a closure *)
 		print ctx "(function (%s) { \"use strict\"" (String.concat ", " (List.map fst closureArgs));
 		newline ctx;
@@ -1953,17 +1954,22 @@ let generate js_gen com =
 		| _ -> ()
 	) include_files;
 
-	if (not ctx.js_modern) then
-		print ctx "var %s = %s;\n" (fst var_global) (snd var_global)
-	else if ctx.js_module_type = Es then
+	(* Define global object *)
+	(match ctx.js_module_type with
+	| Es ->
 		if has_feature ctx "js.Lib.global" || has_feature ctx "use.$bind" || has_feature ctx "$global.$haxeUID" then
-			print ctx "const %s = %s;\n" (fst var_global) (snd var_global);
+			print ctx "const %s = %s;\n" (fst var_global) (snd var_global)
+	| Iife ->
+		() (* provided by the closure *)
+	| Classic ->
+		print ctx "var %s = %s;\n" (fst var_global) (snd var_global)
+	);
 
 	let enums_as_objects = not (Gctx.defined com Define.JsEnumsAsArrays) in
 
 	(* TODO: fix $estr *)
 	let vars = [] in
-	let vars = (if ctx.has_resolveClass || (not enums_as_objects && has_feature ctx "Type.resolveEnum") then ("$hxClasses = " ^ (if ctx.js_modern then "{}" else "$hxClasses || {}")) :: vars else vars) in
+	let vars = (if ctx.has_resolveClass || (not enums_as_objects && has_feature ctx "Type.resolveEnum") then ("$hxClasses = " ^ (if ctx.js_module_type <> Classic then "{}" else "$hxClasses || {}")) :: vars else vars) in
 	let vars = if has_feature ctx "has_enum"
 		then ("$estr = function() { return " ^ (ctx.type_accessor (TClassDecl { null_class with cl_path = ["js"],"Boot" })) ^ ".__string_rec(this,''); }") :: vars
 		else vars in
@@ -2054,7 +2060,7 @@ let generate js_gen com =
 	| None -> ()
 	| Some e -> gen_expr ctx e; newline ctx);
 
-	if (ctx.js_modern && ctx.js_module_type = Iife) then begin
+	if (ctx.js_module_type = Iife) then begin
 		let closureArgs =
 			if has_feature ctx "js.Lib.global" || defined_global then
 				closureArgs

From 93af98adb1e8f82f2071a7b856934458b9aca530 Mon Sep 17 00:00:00 2001
From: Frixuu <code@frixuu.fyi>
Date: Thu, 23 Apr 2026 02:18:21 +0200
Subject: [PATCH 10/16] Clarify `-D shallow-expose` does nothing when
 targetting ES modules; fix #7366

---
 src-json/define.json    |  2 +-
 src/generators/genjs.ml | 18 ++++++++++++------
 2 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/src-json/define.json b/src-json/define.json
index b63a47a1344..88fccd4631e 100644
--- a/src-json/define.json
+++ b/src-json/define.json
@@ -752,7 +752,7 @@
 	{
 		"name": "ShallowExpose",
 		"define": "shallow-expose",
-		"doc": "Expose types to surrounding scope of Haxe generated closure without writing to window object.",
+		"doc": "Expose types to surrounding scope of Haxe generated closure without writing to window object. Does nothing in ESM mode.",
 		"platforms": ["js"]
 	},
 	{
diff --git a/src/generators/genjs.ml b/src/generators/genjs.ml
index b8570f0484c..7f1453bf290 100644
--- a/src/generators/genjs.ml
+++ b/src/generators/genjs.ml
@@ -1916,11 +1916,17 @@ let generate js_gen com =
 		(* Add node globals to pseudo-keywords, so they are not shadowed by local vars *)
 		List.iter (fun s -> Hashtbl.replace kwds2 s ()) [ "global"; "process"; "__filename"; "__dirname"; "module" ];
 
-	if (anyExposed && ((Gctx.defined com Define.ShallowExpose) || ctx.js_module_type = Classic)) then (
-		print ctx "var %s = %s" (fst var_exports) (snd var_exports);
-		ctx.separator <- true;
-		newline ctx
-	);
+	if anyExposed then begin
+		if (Gctx.defined com Define.ShallowExpose) && ctx.js_module_type <> Es then begin
+			print ctx "var %s = %s || {}" (fst var_exports) (fst var_exports);
+			ctx.separator <- true;
+			newline ctx
+		end else if ctx.js_module_type = Classic then begin
+			print ctx "var %s = %s" (fst var_exports) (snd var_exports);
+			ctx.separator <- true;
+			newline ctx
+		end;
+	end;
 
 	if (ctx.js_module_type = Iife) then begin
 		(* Wrap output in a closure *)
@@ -2076,7 +2082,7 @@ let generate js_gen com =
 		newline ctx;
 	end;
 
-	if (anyExposed && (Gctx.defined com Define.ShallowExpose)) then (
+	if (anyExposed && (Gctx.defined com Define.ShallowExpose) && ctx.js_module_type <> Es) then (
 		List.iter (fun f ->
 			print ctx "var %s = $hx_exports%s" f.os_name (path_to_brackets f.os_name);
 			ctx.separator <- true;

From cdec984639b06d14b44ec739bafd0a579e0a2c2e Mon Sep 17 00:00:00 2001
From: Frixuu <code@frixuu.fyi>
Date: Thu, 23 Apr 2026 12:16:01 +0200
Subject: [PATCH 11/16] Fix package object being created in the wrong scope
 when targetting ESM

---
 src/generators/genjs.ml | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/generators/genjs.ml b/src/generators/genjs.ml
index 7f1453bf290..0e5f741d224 100644
--- a/src/generators/genjs.ml
+++ b/src/generators/genjs.ml
@@ -1012,7 +1012,8 @@ let generate_package_create ctx (p,_) =
 			| [] ->
 				(match ctx.js_module_type with
 				| Classic -> print ctx "var %s = %s || {}" p p
-				| _ ->       print ctx "var %s = {}" p)
+				| Iife ->    print ctx "var %s = {}" p
+				| Es ->      print ctx "const %s = {}" p)
 			| _ ->
 				let p = String.concat "." (List.rev acc) ^ (field p) in
 				(match ctx.js_module_type with

From f94ee7e477907a76c8d7b48cf25d0d357ed9ba2e Mon Sep 17 00:00:00 2001
From: Frixuu <code@frixuu.fyi>
Date: Thu, 23 Apr 2026 13:34:38 +0200
Subject: [PATCH 12/16] Disallow `:jsRequire` and `js.Lib.require` in non-Node
 ES modules

---
 src/generators/genjs.ml | 21 ++++++++++++++++++++-
 std/js/Lib.hx           |  2 +-
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/src/generators/genjs.ml b/src/generators/genjs.ml
index 0e5f741d224..4f723bd2914 100644
--- a/src/generators/genjs.ml
+++ b/src/generators/genjs.ml
@@ -37,6 +37,7 @@ type ctx = {
 	smap : sourcemap option;
 	js_flatten : bool;
 	js_module_type : js_module_type;
+	mutable es_synthetic_require_generated : bool;
 	has_resolveClass : bool;
 	has_interface_check : bool;
 	es_version : int;
@@ -1620,12 +1621,26 @@ let generate_static ctx (c,f,e) =
 			generate_export_statement ctx expr s
 		)
 
+let generate_create_require_once ctx =
+	if ctx.js_module_type = Es then
+		if (not (Gctx.raw_defined ctx.com "nodejs")) then
+			failwith "Cannot require() in an ES module.\nIf you are using Node.js, use `--define nodejs` to enable CommonJS module loading,\nor use a different `--define js.module` type, like `iife`."
+		else if not ctx.es_synthetic_require_generated then begin
+			ctx.es_synthetic_require_generated <- true;
+			spr ctx "import { createRequire } from \"node:module\"";
+			newline ctx;
+			spr ctx "const require = createRequire(import.meta.url)";
+			newline ctx;
+		end
+
 let generate_require ctx path meta =
 	let _, args, mp = Meta.get Meta.JsRequire meta in
 	let p = (s_path ctx path) in
 
+	generate_create_require_once ctx;
+
 	if ctx.js_flatten then
-		spr ctx "var "
+		spr ctx (if ctx.js_module_type = Es then "const " else "var ")
 	else
 		generate_package_create ctx path;
 
@@ -1706,6 +1721,7 @@ let alloc_ctx com es_version =
 				| _ -> failwith "Invalid `js.module` define. Use `es`, `iife`, or `classic`"
 			)	
 		end;
+		es_synthetic_require_generated = false;
 		has_resolveClass = Gctx.has_feature com "Type.resolveClass";
 		has_interface_check = Gctx.has_feature com "js.Boot.__interfLoop";
 		es_version = es_version;
@@ -1821,6 +1837,9 @@ let generate js_gen com =
 			) (List.rev lines)
 	);
 
+	if has_feature ctx "js.Lib.require" then
+		generate_create_require_once ctx;
+
 	if has_feature ctx "Class" || has_feature ctx "Type.getClassName" then add_feature ctx "js.Boot.isClass";
 	if has_feature ctx "Enum" || has_feature ctx "Type.getEnumName" then add_feature ctx "js.Boot.isEnum";
 
diff --git a/std/js/Lib.hx b/std/js/Lib.hx
index 4b966d99bbc..486a7ff798d 100644
--- a/std/js/Lib.hx
+++ b/std/js/Lib.hx
@@ -63,7 +63,7 @@ class Lib {
 		is available, such as Node.js or RequireJS.
 	**/
 	extern public static inline function require(module:String):Dynamic {
-		return js.Syntax.code("require")(module);
+		return untyped __define_feature__("js.Lib.require", js.Syntax.code("require")(module));
 	}
 
 	/**

From cff47062a7ad57b816bb2ba527c7ba7384e6c82a Mon Sep 17 00:00:00 2001
From: Frixuu <code@frixuu.fyi>
Date: Thu, 23 Apr 2026 16:51:33 +0200
Subject: [PATCH 13/16] Always generate `$global`, even in ESM context

---
 src/generators/genjs.ml | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/generators/genjs.ml b/src/generators/genjs.ml
index 4f723bd2914..0321fb2ea24 100644
--- a/src/generators/genjs.ml
+++ b/src/generators/genjs.ml
@@ -1923,7 +1923,12 @@ let generate js_gen com =
 
 	let var_global = (
 		"$global",
-		typeof_join (if defined_global then [defined_global_value] else ["globalThis"; "window"; "global"; "self"; "this"])
+		typeof_join (if defined_global then
+			[defined_global_value]
+		else if ctx.es_version >= 2020 then
+			["globalThis"]
+		else
+			["globalThis"; "window"; "global"; "self"; "this"])
 	) in
 
 	let closureArgs = [var_global] in
@@ -1983,8 +1988,7 @@ let generate js_gen com =
 	(* Define global object *)
 	(match ctx.js_module_type with
 	| Es ->
-		if has_feature ctx "js.Lib.global" || has_feature ctx "use.$bind" || has_feature ctx "$global.$haxeUID" then
-			print ctx "const %s = %s;\n" (fst var_global) (snd var_global)
+		print ctx "const %s = %s;\n" (fst var_global) (snd var_global)
 	| Iife ->
 		() (* provided by the closure *)
 	| Classic ->

From c7aa3039297ebd34a3cb9e83c7cab29f73ca195a Mon Sep 17 00:00:00 2001
From: Frixuu <code@frixuu.fyi>
Date: Thu, 23 Apr 2026 16:06:26 +0200
Subject: [PATCH 14/16] Run more JS test permutations

---
 tests/runci/targets/Js.hx               | 20 ++++++++++++++------
 tests/unit/src/unit/issues/Issue8710.hx |  4 +++-
 2 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/tests/runci/targets/Js.hx b/tests/runci/targets/Js.hx
index 67cab7ef869..46dcc88e689 100644
--- a/tests/runci/targets/Js.hx
+++ b/tests/runci/targets/Js.hx
@@ -45,19 +45,27 @@ class Js {
 		getJSDependencies();
 
 		final jsOutputs = [
-			for (es_ver in    [[], ["-D", "js-es=6"]])
-			for (unflatten in [[], ["-D", "js-unflatten"]])
-			for (classic in   [[], ["-D", "js-classic"]])
+			for (es_ver in           [[], ["-D", "js-es=6"], ["-D", "js-es=2022" /* the newest Node v18 supports */]])
+			for (unflatten in        [[], ["-D", "js-unflatten"]])
+			for (moduleType in       [[], ["-D", "js.module=es"], ["-D", "js.module=classic"]])
 			for (enums_as_objects in [[], ["-D", "js-enums-as-arrays"]])
 			{
-				final extras = args.concat(es_ver).concat(unflatten).concat(classic).concat(enums_as_objects);
+				final esm = moduleType.length == 2 && moduleType[1].endsWith("es");
+
+				// Skip ESM tests for ES5
+				if (es_ver.length == 0 && esm) {
+					continue;
+				}
+
+				final extras = args.concat(es_ver).concat(unflatten).concat(moduleType).concat(enums_as_objects);
 
 				runCommand("haxe", ["compile-js.hxml"].concat(extras));
 
+				final extension = esm ? "mjs" : "js"; // Node v18 and below cannot automatically detect module type
 				final output = if (extras.length > 0) {
-					"bin/js/" + extras.join("") + "/unit.js";
+					"bin/js/" + extras.join("") + '/unit.${extension}';
 				} else {
-					"bin/js/default/unit.js";
+					'bin/js/default/unit.${extension}';
 				}
 				final outputDir = Path.directory(output);
 				if (!FileSystem.exists(outputDir))
diff --git a/tests/unit/src/unit/issues/Issue8710.hx b/tests/unit/src/unit/issues/Issue8710.hx
index 942b5a0147a..a57a5cca6dd 100644
--- a/tests/unit/src/unit/issues/Issue8710.hx
+++ b/tests/unit/src/unit/issues/Issue8710.hx
@@ -7,7 +7,9 @@ class Issue8710 extends unit.Test {
 
 	function test() {
 		var actual =
-			#if js
+			#if (js && js.module == "es") 
+				js.Syntax.code("exposed");
+			#elseif js
 				js.Syntax.code("$hx_exports[\"exposed\"]");
 			#elseif lua
 				untyped __lua__("_hx_exports[\"exposed\"]");

From f480af026d3d14dcd0010898f069f09d5de480a6 Mon Sep 17 00:00:00 2001
From: Frixuu <code@frixuu.fyi>
Date: Fri, 24 Apr 2026 18:55:15 +0200
Subject: [PATCH 15/16] [js] Revise when exports in ES modules do declare a
 helper variable

---
 src/generators/genjs.ml                 | 26 +++++++++++-----------
 tests/unit/src/unit/issues/Issue8710.hx | 29 ++++++++++++++++++-------
 2 files changed, 34 insertions(+), 21 deletions(-)

diff --git a/src/generators/genjs.ml b/src/generators/genjs.ml
index 0321fb2ea24..432f9455e7b 100644
--- a/src/generators/genjs.ml
+++ b/src/generators/genjs.ml
@@ -1041,28 +1041,28 @@ let path_to_brackets path =
 	"[\"" ^ (String.concat "\"][\"" parts) ^ "\"]"
 
 let mangle_export_name_es6 ctx ident =
-	if ctx.es_version >= 2022 then
+	if not (ExtString.String.contains ident '.') then
+		ident
+	else if ctx.es_version >= 2022 then
 		(* Keyword: "arbitrary module namespace identifier names" *)
 		Printf.sprintf "\"%s\"" ident
 	else
 		let parts = ExtString.String.nsplit ident "." in
 		String.concat "_" parts
 
-let tmp_var_counter = ref 0
-let export_tmp_name() = 
-	let name = Printf.sprintf "$hx_export_tmp_%d" !tmp_var_counter in
-	tmp_var_counter := !tmp_var_counter + 1;
-	name
-
+let tmp_export_vars = Atomic.make 0
 let generate_export_statement ctx expr ident =
 	if ctx.js_module_type == Es then
-		let ident_contains_dots = ExtString.String.contains ident '.' in
-		if (not ident_contains_dots) && expr <> ident then
-			print ctx "export const %s = %s;" ident expr
+		let ident = mangle_export_name_es6 ctx ident in
+		let expr_contains_dots = ExtString.String.contains expr '.' in
+		if not expr_contains_dots then
+			if expr = ident then
+				print ctx "export { %s };" ident
+			else
+				print ctx "export { %s as %s };" expr ident
 		else begin
-			let tmp_name = export_tmp_name() in
-			let exported_name = if ident_contains_dots then mangle_export_name_es6 ctx ident else ident in
-			print ctx "const %s = %s; export {%s as %s};" tmp_name expr tmp_name exported_name
+			let tmp_name = Printf.sprintf "$hx_export_tmp_%d" (Atomic.fetch_and_add tmp_export_vars 1) in
+			print ctx "const %s = %s; export { %s as %s };" tmp_name expr tmp_name ident
 		end
 	else
 		print ctx "$hx_exports%s = %s;" (path_to_brackets ident) expr;
diff --git a/tests/unit/src/unit/issues/Issue8710.hx b/tests/unit/src/unit/issues/Issue8710.hx
index a57a5cca6dd..3851284d6c0 100644
--- a/tests/unit/src/unit/issues/Issue8710.hx
+++ b/tests/unit/src/unit/issues/Issue8710.hx
@@ -1,20 +1,33 @@
 package unit.issues;
 
 class Issue8710 extends unit.Test {
-#if (js || lua)
+	#if (js || lua)
 	@:expose('exposed')
 	static var field = 10 + Std.random(1);
 
+	#if (js && js.module == "es")
+	// ESM exports are not easily accessible as variables.
+	// To circumvent this, dynamically import current module:
+	function test(async:utest.Async) {
+		js.Lib.dynamicImport(js.Syntax.code("import.meta.url")).then(module -> {
+			var actual = module.exposed;
+			eq(10, actual);
+			async.done();
+		}).catchError(e -> {
+			assert(Std.string(e));
+			async.done();
+		});
+	}
+	#else
 	function test() {
 		var actual =
-			#if (js && js.module == "es") 
-				js.Syntax.code("exposed");
-			#elseif js
-				js.Syntax.code("$hx_exports[\"exposed\"]");
+			#if js
+			js.Syntax.code("$hx_exports[\"exposed\"]");
 			#elseif lua
-				untyped __lua__("_hx_exports[\"exposed\"]");
+			untyped __lua__("_hx_exports[\"exposed\"]");
 			#end
 		eq(10, actual);
 	}
-#end
-}
\ No newline at end of file
+	#end
+	#end
+}

From 5d3925090f4f08ac07df3717578d1ba43d84cd96 Mon Sep 17 00:00:00 2001
From: Frixuu <code@frixuu.fyi>
Date: Mon, 27 Apr 2026 01:30:58 +0200
Subject: [PATCH 16/16] Do not define enums in ES modules as `var`

---
 src/generators/genjs.ml | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/generators/genjs.ml b/src/generators/genjs.ml
index 432f9455e7b..8d1659378c0 100644
--- a/src/generators/genjs.ml
+++ b/src/generators/genjs.ml
@@ -1495,7 +1495,7 @@ let generate_enum ctx e =
 	let dotp = dot_path e.e_path in
 	let has_enum_feature = has_feature ctx "has_enum" in
 	if ctx.js_flatten then
-		print ctx "var "
+		print ctx (if ctx.js_module_type = Es then "const " else "var ")
 	else
 		generate_package_create ctx e.e_path;
 	print ctx "%s = " p;
@@ -2003,7 +2003,7 @@ let generate js_gen com =
 	let vars = if has_feature ctx "has_enum"
 		then ("$estr = function() { return " ^ (ctx.type_accessor (TClassDecl { null_class with cl_path = ["js"],"Boot" })) ^ ".__string_rec(this,''); }") :: vars
 		else vars in
-	let vars = if (enums_as_objects && (has_feature ctx "has_enum" || has_feature ctx "Type.resolveEnum")) then "$hxEnums = $hxEnums || {}" :: vars else vars in
+	let vars = if (enums_as_objects && (has_feature ctx "has_enum" || has_feature ctx "Type.resolveEnum")) then ("$hxEnums = " ^ (if ctx.js_module_type = Es then "{}" else "$hxEnums || {}")) :: vars else vars in
 	let vars,has_dollar_underscore =
 		if List.exists (function TEnumDecl e when not (has_enum_flag e EnExtern) -> true | _ -> false) com.types then
 			"$_" :: vars,ref true
@@ -2013,7 +2013,8 @@ let generate js_gen com =
 	(match List.rev vars with
 	| [] -> ()
 	| vl ->
-		print ctx "var %s" (String.concat "," vl);
+		let kwd = if ctx.js_module_type = Es then "let" else "var" in
+		print ctx "%s %s" kwd (String.concat ", " vl);
 		ctx.separator <- true;
 		newline ctx
 	);