diff --git a/src/ant.c b/src/ant.c
index 2e384e4..4c2caff 100644
--- a/src/ant.c
+++ b/src/ant.c
@@ -2744,7 +2744,6 @@ typedef struct {
 } ant_arguments_state_t;
 
 static inline ant_arguments_state_t *js_arguments_state(ant_value_t obj) {
-  if (!js_check_native_tag(obj, ANT_ARGUMENTS_NATIVE_TAG)) return NULL;
   return (ant_arguments_state_t *)js_get_native(obj, ANT_ARGUMENTS_NATIVE_TAG);
 }
 
diff --git a/src/modules/abort.c b/src/modules/abort.c
index 8795fd6..dc0131b 100644
--- a/src/modules/abort.c
+++ b/src/modules/abort.c
@@ -52,7 +52,6 @@ static inline unsigned int abort_array_len(UT_array *arr) {
 }
 
 static abort_signal_data_t *get_signal_data(ant_value_t obj) {
-  if (!js_check_native_tag(obj, ABORT_SIGNAL_NATIVE_TAG)) return NULL;
   return (abort_signal_data_t *)js_get_native(obj, ABORT_SIGNAL_NATIVE_TAG);
 }
 
diff --git a/src/modules/blob.c b/src/modules/blob.c
index d914a57..7cc21a5 100644
--- a/src/modules/blob.c
+++ b/src/modules/blob.c
@@ -29,7 +29,6 @@ bool blob_is_blob(ant_t *js, ant_value_t obj) {
 }
 
 blob_data_t *blob_get_data(ant_value_t obj) {
-  if (!js_check_native_tag(obj, BLOB_NATIVE_TAG)) return NULL;
   return (blob_data_t *)js_get_native(obj, BLOB_NATIVE_TAG);
 }
 
diff --git a/src/modules/buffer.c b/src/modules/buffer.c
index 3967105..c3bd1c0 100644
--- a/src/modules/buffer.c
+++ b/src/modules/buffer.c
@@ -56,41 +56,34 @@ static void ta_meta_free(void *ptr, size_t size) {
 
 ArrayBufferData *buffer_get_arraybuffer_data(ant_value_t value) {
   if (!is_object_type(value) || buffer_is_dataview(value)) return NULL;
-  if (js_check_native_tag(value, BUFFER_ARRAYBUFFER_NATIVE_TAG))
-    return (ArrayBufferData *)js_get_native(value, BUFFER_ARRAYBUFFER_NATIVE_TAG);
-  return NULL;
+  return (ArrayBufferData *)js_get_native(value, BUFFER_ARRAYBUFFER_NATIVE_TAG);
 }
 
 TypedArrayData *buffer_get_typedarray_data(ant_value_t value) {
   if (vtype(value) == T_TYPEDARRAY)
     return (TypedArrayData *)js_gettypedarray(value);
   if (!is_object_type(value)) return NULL;
-  if (js_check_native_tag(value, BUFFER_TYPEDARRAY_NATIVE_TAG))
-    return (TypedArrayData *)js_get_native(value, BUFFER_TYPEDARRAY_NATIVE_TAG);
-  return NULL;
+  return (TypedArrayData *)js_get_native(value, BUFFER_TYPEDARRAY_NATIVE_TAG);
 }
 
 DataViewData *buffer_get_dataview_data(ant_value_t value) {
   if (!is_object_type(value)) return NULL;
-  if (js_check_native_tag(value, BUFFER_DATAVIEW_NATIVE_TAG))
-    return (DataViewData *)js_get_native(value, BUFFER_DATAVIEW_NATIVE_TAG);
-  return NULL;
+  return (DataViewData *)js_get_native(value, BUFFER_DATAVIEW_NATIVE_TAG);
 }
 
 static void arraybuffer_finalize(ant_t *js, ant_object_t *obj) {
   ant_value_t value = js_obj_from_ptr(obj);
-  if (!js_check_native_tag(value, BUFFER_ARRAYBUFFER_NATIVE_TAG)) return;
   ArrayBufferData *data = (ArrayBufferData *)js_get_native(value, BUFFER_ARRAYBUFFER_NATIVE_TAG);
+  if (!data) return;
   js_clear_native(value, BUFFER_ARRAYBUFFER_NATIVE_TAG);
-  if (data) free_array_buffer_data(data);
+  free_array_buffer_data(data);
 }
 
 static void typedarray_finalize(ant_t *js, ant_object_t *obj) {
   ant_value_t value = js_obj_from_ptr(obj);
-  if (!js_check_native_tag(value, BUFFER_TYPEDARRAY_NATIVE_TAG)) return;
   TypedArrayData *ta_data = (TypedArrayData *)js_get_native(value, BUFFER_TYPEDARRAY_NATIVE_TAG);
-  js_clear_native(value, BUFFER_TYPEDARRAY_NATIVE_TAG);
   if (!ta_data) return;
+  js_clear_native(value, BUFFER_TYPEDARRAY_NATIVE_TAG);
 
   if (ta_data->buffer) free_array_buffer_data(ta_data->buffer);
   ta_meta_free(ta_data, sizeof(*ta_data));
@@ -98,10 +91,9 @@ static void typedarray_finalize(ant_t *js, ant_object_t *obj) {
 
 static void dataview_finalize(ant_t *js, ant_object_t *obj) {
   ant_value_t value = js_obj_from_ptr(obj);
-  if (!js_check_native_tag(value, BUFFER_DATAVIEW_NATIVE_TAG)) return;
   DataViewData *dv_data = (DataViewData *)js_get_native(value, BUFFER_DATAVIEW_NATIVE_TAG);
-  js_clear_native(value, BUFFER_DATAVIEW_NATIVE_TAG);
   if (!dv_data) return;
+  js_clear_native(value, BUFFER_DATAVIEW_NATIVE_TAG);
 
   if (dv_data->buffer) free_array_buffer_data(dv_data->buffer);
   ta_meta_free(dv_data, sizeof(*dv_data));
diff --git a/src/modules/child_process.c b/src/modules/child_process.c
index 6f17b27..42def00 100644
--- a/src/modules/child_process.c
+++ b/src/modules/child_process.c
@@ -116,12 +116,10 @@ enum {
 };
 
 static child_process_t *get_child_process(ant_value_t obj) {
-  if (!js_check_native_tag(obj, CHILD_PROCESS_NATIVE_TAG)) return NULL;
   return (child_process_t *)js_get_native(obj, CHILD_PROCESS_NATIVE_TAG);
 }
 
 static child_stream_ctx_t *get_child_stream_ctx(ant_value_t obj) {
-  if (!js_check_native_tag(obj, CHILD_STREAM_NATIVE_TAG)) return NULL;
   return (child_stream_ctx_t *)js_get_native(obj, CHILD_STREAM_NATIVE_TAG);
 }
 static child_process_t *pending_children_tail = NULL;
diff --git a/src/modules/collections.c b/src/modules/collections.c
index 1e1005f..58427f0 100644
--- a/src/modules/collections.c
+++ b/src/modules/collections.c
@@ -309,38 +309,32 @@ static ant_value_t weakset_init_from_iterable(ant_t *js, weakset_entry_t **ws_he
 map_entry_t **get_map_from_obj(ant_value_t obj) {
   ant_object_t *ptr = js_obj_ptr(obj);
   if (!ptr || ptr->type_tag != T_MAP) return NULL;
-  if (!js_check_native_tag(obj, MAP_NATIVE_TAG)) return NULL;
   return (map_entry_t **)js_get_native(obj, MAP_NATIVE_TAG);
 }
 
 set_entry_t **get_set_from_obj(ant_value_t obj) {
   ant_object_t *ptr = js_obj_ptr(obj);
   if (!ptr || ptr->type_tag != T_SET) return NULL;
-  if (!js_check_native_tag(obj, SET_NATIVE_TAG)) return NULL;
   return (set_entry_t **)js_get_native(obj, SET_NATIVE_TAG);
 }
 
 static weakmap_entry_t **get_weakmap_from_obj(ant_value_t obj) {
   ant_object_t *ptr = js_obj_ptr(obj);
   if (!ptr || ptr->type_tag != T_WEAKMAP) return NULL;
-  if (!js_check_native_tag(obj, WEAKMAP_NATIVE_TAG)) return NULL;
   return (weakmap_entry_t **)js_get_native(obj, WEAKMAP_NATIVE_TAG);
 }
 
 static weakset_entry_t **get_weakset_from_obj(ant_value_t obj) {
   ant_object_t *ptr = js_obj_ptr(obj);
   if (!ptr || ptr->type_tag != T_WEAKSET) return NULL;
-  if (!js_check_native_tag(obj, WEAKSET_NATIVE_TAG)) return NULL;
   return (weakset_entry_t **)js_get_native(obj, WEAKSET_NATIVE_TAG);
 }
 
 map_iterator_state_t *get_map_iter_state(ant_value_t obj) {
-  if (!js_check_native_tag(obj, MAP_ITER_NATIVE_TAG)) return NULL;
   return (map_iterator_state_t *)js_get_native(obj, MAP_ITER_NATIVE_TAG);
 }
 
 set_iterator_state_t *get_set_iter_state(ant_value_t obj) {
-  if (!js_check_native_tag(obj, SET_ITER_NATIVE_TAG)) return NULL;
   return (set_iterator_state_t *)js_get_native(obj, SET_ITER_NATIVE_TAG);
 }
 
diff --git a/src/modules/crypto.c b/src/modules/crypto.c
index b05e0f9..78f3b8e 100644
--- a/src/modules/crypto.c
+++ b/src/modules/crypto.c
@@ -222,7 +222,6 @@ static ant_value_t crypto_get_input_bytes(
 }
 
 static ant_hash_state_t *crypto_get_hash_state(ant_value_t value) {
-  if (!js_check_native_tag(value, CRYPTO_HASH_NATIVE_TAG)) return NULL;
   ant_hash_state_t *state = (ant_hash_state_t *)js_get_native(value, CRYPTO_HASH_NATIVE_TAG);
   return (state && state->ctx) ? state : NULL;
 }
diff --git a/src/modules/events.c b/src/modules/events.c
index 842f8b3..8755356 100644
--- a/src/modules/events.c
+++ b/src/modules/events.c
@@ -41,7 +41,6 @@ enum {
 };
 
 static event_data_t *get_event_data(ant_value_t obj) {
-  if (!js_check_native_tag(obj, EVENT_NATIVE_TAG)) return NULL;
   return (event_data_t *)js_get_native(obj, EVENT_NATIVE_TAG);
 }
 
@@ -155,8 +154,9 @@ static bool evt_key_init(ant_t *js, ant_value_t arg, evt_key_t *out) {
 }
 
 static EventType **get_or_create_emitter_events(ant_t *js, ant_value_t this_obj) {
-  if (!js_check_native_tag(this_obj, EVENT_EMITTER_NATIVE_TAG)) {
-    EventType **events = ant_calloc(sizeof(EventType *));
+  EventType **events = (EventType **)js_get_native(this_obj, EVENT_EMITTER_NATIVE_TAG);
+  if (!events) {
+    events = ant_calloc(sizeof(EventType *));
     if (!events) return NULL;
     *events = NULL;
 
@@ -167,9 +167,8 @@ static EventType **get_or_create_emitter_events(ant_t *js, ant_value_t this_obj)
     emitter_registry = reg;
 
     js_set_native(this_obj, events, EVENT_EMITTER_NATIVE_TAG);
-    return events;
   }
-  return (EventType **)js_get_native(this_obj, EVENT_EMITTER_NATIVE_TAG);
+  return events;
 }
 
 static EventType *find_or_create_global_event_type(ant_t *js, ant_value_t js_key) {
diff --git a/src/modules/fetch.c b/src/modules/fetch.c
index b97fea6..1edc69a 100644
--- a/src/modules/fetch.c
+++ b/src/modules/fetch.c
@@ -657,9 +657,7 @@ static bool fetch_handle_data_url(fetch_request_t *req) {
 }
 
 static ant_value_t fetch_upload_on_reject(ant_t *js, ant_value_t *args, int nargs) {
-  fetch_request_t *req = js_check_native_tag(js->current_func, FETCH_REQUEST_NATIVE_TAG)
-    ? (fetch_request_t *)js_get_native(js->current_func, FETCH_REQUEST_NATIVE_TAG)
-    : NULL;
+  fetch_request_t *req = (fetch_request_t *)js_get_native(js->current_func, FETCH_REQUEST_NATIVE_TAG);
   ant_value_t reason = (nargs > 0) ? args[0] : js_mkundef();
 
   if (!req) return js_mkundef();
@@ -677,9 +675,7 @@ static ant_value_t fetch_upload_on_reject(ant_t *js, ant_value_t *args, int narg
 
 static void fetch_upload_schedule_next_read(fetch_request_t *req);
 static ant_value_t fetch_upload_on_read(ant_t *js, ant_value_t *args, int nargs) {
-  fetch_request_t *req = js_check_native_tag(js->current_func, FETCH_REQUEST_NATIVE_TAG)
-    ? (fetch_request_t *)js_get_native(js->current_func, FETCH_REQUEST_NATIVE_TAG)
-    : NULL;
+  fetch_request_t *req = (fetch_request_t *)js_get_native(js->current_func, FETCH_REQUEST_NATIVE_TAG);
   
   ant_value_t result = (nargs > 0) ? args[0] : js_mkundef();
   ant_value_t done = 0;
@@ -838,9 +834,7 @@ static void fetch_start_http(fetch_request_t *req) {
 }
 
 static ant_value_t fetch_abort_listener(ant_t *js, ant_value_t *args, int nargs) {
-  fetch_request_t *req = js_check_native_tag(js->current_func, FETCH_REQUEST_NATIVE_TAG)
-    ? (fetch_request_t *)js_get_native(js->current_func, FETCH_REQUEST_NATIVE_TAG)
-    : NULL;
+  fetch_request_t *req = (fetch_request_t *)js_get_native(js->current_func, FETCH_REQUEST_NATIVE_TAG);
   ant_value_t signal = 0;
   ant_value_t reason = 0;
 
diff --git a/src/modules/ffi.c b/src/modules/ffi.c
index 8d91448..e1384c4 100644
--- a/src/modules/ffi.c
+++ b/src/modules/ffi.c
@@ -346,22 +346,18 @@ static ffi_marshaled_type_t ffi_infer_variadic_type(ant_value_t value) {
 }
 
 static ffi_library_handle_t *ffi_library_data(ant_value_t value) {
-  if (!js_check_native_tag(value, FFI_LIBRARY_NATIVE_TAG)) return NULL;
   return (ffi_library_handle_t *)js_get_native(value, FFI_LIBRARY_NATIVE_TAG);
 }
 
 static ffi_function_handle_t *ffi_function_data(ant_value_t value) {
-  if (!js_check_native_tag(value, FFI_FUNCTION_NATIVE_TAG)) return NULL;
   return (ffi_function_handle_t *)js_get_native(value, FFI_FUNCTION_NATIVE_TAG);
 }
 
 static ffi_pointer_handle_t *ffi_pointer_data(ant_value_t value) {
-  if (!js_check_native_tag(value, FFI_POINTER_NATIVE_TAG)) return NULL;
   return (ffi_pointer_handle_t *)js_get_native(value, FFI_POINTER_NATIVE_TAG);
 }
 
 static ffi_callback_handle_t *ffi_callback_data(ant_value_t value) {
-  if (!js_check_native_tag(value, FFI_CALLBACK_NATIVE_TAG)) return NULL;
   return (ffi_callback_handle_t *)js_get_native(value, FFI_CALLBACK_NATIVE_TAG);
 }
 
diff --git a/src/modules/formdata.c b/src/modules/formdata.c
index 45eb575..96f6301 100644
--- a/src/modules/formdata.c
+++ b/src/modules/formdata.c
@@ -70,7 +70,6 @@ static void fd_data_free(fd_data_t *d) {
 }
 
 static fd_data_t *get_fd_data(ant_value_t obj) {
-  if (!js_check_native_tag(obj, FORMDATA_NATIVE_TAG)) return NULL;
   return (fd_data_t *)js_get_native(obj, FORMDATA_NATIVE_TAG);
 }
 
@@ -379,10 +378,8 @@ static ant_value_t js_formdata_foreach(ant_t *js, ant_value_t *args, int nargs)
 }
 
 static ant_value_t formdata_iter_next(ant_t *js, ant_value_t *args, int nargs) {
-  if (!js_check_native_tag(js->this_val, FORMDATA_ITER_NATIVE_TAG))
-    return js_iter_result(js, false, js_mkundef());
-
   fd_iter_t *st = (fd_iter_t *)js_get_native(js->this_val, FORMDATA_ITER_NATIVE_TAG);
+  if (!st) return js_iter_result(js, false, js_mkundef());
   ant_value_t fd_obj = js_get_slot(js->this_val, SLOT_DATA);
   fd_data_t *d = get_fd_data(fd_obj);
   if (!d) return js_iter_result(js, false, js_mkundef());
diff --git a/src/modules/fs.c b/src/modules/fs.c
index 6e7a661..e4e3a51 100644
--- a/src/modules/fs.c
+++ b/src/modules/fs.c
@@ -157,7 +157,6 @@ enum {
 };
 
 static fs_watcher_t *fs_watcher_data(ant_value_t value) {
-  if (!js_check_native_tag(value, FS_WATCHER_NATIVE_TAG)) return NULL;
   return (fs_watcher_t *)js_get_native(value, FS_WATCHER_NATIVE_TAG);
 }
 
diff --git a/src/modules/generator.c b/src/modules/generator.c
index c583092..84a789f 100644
--- a/src/modules/generator.c
+++ b/src/modules/generator.c
@@ -51,7 +51,6 @@ static ant_value_t generator_result(ant_t *js, bool done, ant_value_t value) {
 }
 
 static generator_data_t *generator_data(ant_value_t gen) {
-  if (!js_check_native_tag(gen, GENERATOR_NATIVE_TAG)) return NULL;
   return (generator_data_t *)js_get_native(gen, GENERATOR_NATIVE_TAG);
 }
 
diff --git a/src/modules/headers.c b/src/modules/headers.c
index 853b40a..2ec15a7 100644
--- a/src/modules/headers.c
+++ b/src/modules/headers.c
@@ -70,7 +70,6 @@ static void list_free(hdr_list_t *l) {
 }
 
 static hdr_list_t *get_list(ant_value_t obj) {
-  if (!js_check_native_tag(obj, HEADERS_NATIVE_TAG)) return NULL;
   return (hdr_list_t *)js_get_native(obj, HEADERS_NATIVE_TAG);
 }
 
@@ -479,8 +478,8 @@ static ant_value_t init_from_record(ant_t *js, hdr_list_t *l, ant_value_t obj) {
 }
 
 bool advance_headers(ant_t *js, js_iter_t *it, ant_value_t *out) {
-  if (!js_check_native_tag(it->iterator, HEADERS_ITER_NATIVE_TAG)) return false;
   hdr_iter_t *st = (hdr_iter_t *)js_get_native(it->iterator, HEADERS_ITER_NATIVE_TAG);
+  if (!st) return false;
 
   size_t count = 0;
   sorted_pair_t *view = build_sorted_view(st->list, &count);
diff --git a/src/modules/iterator.c b/src/modules/iterator.c
index 92c493c..5e5daa9 100644
--- a/src/modules/iterator.c
+++ b/src/modules/iterator.c
@@ -890,7 +890,6 @@ static void async_terminal_state_finalize(ant_t *js, ant_object_t *obj) {
 }
 
 static inline async_terminal_state_t *async_terminal_state(ant_value_t state) {
-  if (!js_check_native_tag(state, ASYNC_TERMINAL_STATE_TAG)) return NULL;
   return (async_terminal_state_t *)js_get_native(state, ASYNC_TERMINAL_STATE_TAG);
 }
 
diff --git a/src/modules/napi.c b/src/modules/napi.c
index b5a038e..ef13677 100644
--- a/src/modules/napi.c
+++ b/src/modules/napi.c
@@ -481,8 +481,6 @@ static int napi_desc_flags(napi_property_attributes attributes) {
 
 static ant_value_t napi_callback_trampoline(ant_t *js, ant_value_t *args, int nargs) {
   ant_value_t current = js_getcurrentfunc(js);
-  if (!js_check_native_tag(current, NAPI_CALLBACK_NATIVE_TAG)) return js_mkundef();
-
   napi_callback_binding_t *binding = (napi_callback_binding_t *)js_get_native(current, NAPI_CALLBACK_NATIVE_TAG);
   if (!binding || !binding->cb) return js_mkundef();
 
diff --git a/src/modules/net.c b/src/modules/net.c
index 3186841..590eff1 100644
--- a/src/modules/net.c
+++ b/src/modules/net.c
@@ -101,12 +101,10 @@ enum {
 static ant_value_t net_not_implemented(ant_t *js, const char *what);
 
 static net_server_t *net_server_data(ant_value_t value) {
-  if (!js_check_native_tag(value, NET_SERVER_NATIVE_TAG)) return NULL;
   return (net_server_t *)js_get_native(value, NET_SERVER_NATIVE_TAG);
 }
 
 static net_socket_t *net_socket_data(ant_value_t value) {
-  if (!js_check_native_tag(value, NET_SOCKET_NATIVE_TAG)) return NULL;
   return (net_socket_t *)js_get_native(value, NET_SOCKET_NATIVE_TAG);
 }
 
diff --git a/src/modules/request.c b/src/modules/request.c
index b58d666..c8407ed 100644
--- a/src/modules/request.c
+++ b/src/modules/request.c
@@ -31,7 +31,6 @@ ant_value_t g_request_proto = 0;
 enum { REQUEST_NATIVE_TAG = 0x52455153u }; // REQS
 
 static request_data_t *get_data(ant_value_t obj) {
-  if (!js_check_native_tag(obj, REQUEST_NATIVE_TAG)) return NULL;
   return (request_data_t *)js_get_native(obj, REQUEST_NATIVE_TAG);
 }
 
diff --git a/src/modules/response.c b/src/modules/response.c
index bd90651..7ac54e2 100644
--- a/src/modules/response.c
+++ b/src/modules/response.c
@@ -31,7 +31,6 @@ ant_value_t g_response_proto = 0;
 enum { RESPONSE_NATIVE_TAG = 0x52455350u }; // RESP
 
 static response_data_t *get_data(ant_value_t obj) {
-  if (!js_check_native_tag(obj, RESPONSE_NATIVE_TAG)) return NULL;
   return (response_data_t *)js_get_native(obj, RESPONSE_NATIVE_TAG);
 }
 
diff --git a/src/modules/string_decoder.c b/src/modules/string_decoder.c
index 3d1fa70..3a2e577 100644
--- a/src/modules/string_decoder.c
+++ b/src/modules/string_decoder.c
@@ -34,7 +34,6 @@ static ant_value_t g_string_decoder_proto = 0;
 enum { STRING_DECODER_NATIVE_TAG = 0x53444543u }; // SDEC
 
 static sd_state_t *sd_get_state(ant_value_t obj) {
-  if (!js_check_native_tag(obj, STRING_DECODER_NATIVE_TAG)) return NULL;
   return (sd_state_t *)js_get_native(obj, STRING_DECODER_NATIVE_TAG);
 }
 
diff --git a/src/modules/textcodec.c b/src/modules/textcodec.c
index 89229b5..aaca43e 100644
--- a/src/modules/textcodec.c
+++ b/src/modules/textcodec.c
@@ -29,7 +29,6 @@ td_state_t *td_state_new(td_encoding_t enc, bool fatal, bool ignore_bom) {
 }
 
 static td_state_t *td_get_state(ant_value_t obj) {
-  if (!js_check_native_tag(obj, TEXT_DECODER_NATIVE_TAG)) return NULL;
   return (td_state_t *)js_get_native(obj, TEXT_DECODER_NATIVE_TAG);
 }
 
diff --git a/src/modules/tls.c b/src/modules/tls.c
index 9330923..3c047f2 100644
--- a/src/modules/tls.c
+++ b/src/modules/tls.c
@@ -40,7 +40,6 @@ static void tls_context_free(ant_tls_context_wrap_t *wrap) {
 }
 
 static ant_tls_context_wrap_t *tls_context_data(ant_value_t value) {
-  if (!js_check_native_tag(value, TLS_CONTEXT_NATIVE_TAG)) return NULL;
   return (ant_tls_context_wrap_t *)js_get_native(value, TLS_CONTEXT_NATIVE_TAG);
 }
 
diff --git a/src/modules/url.c b/src/modules/url.c
index 30eed97..8c10a65 100644
--- a/src/modules/url.c
+++ b/src/modules/url.c
@@ -30,7 +30,6 @@ enum {
 };
 
 url_state_t *url_get_state(ant_value_t obj) {
-  if (!js_check_native_tag(obj, URL_NATIVE_TAG)) return NULL;
   return (url_state_t *)js_get_native(obj, URL_NATIVE_TAG);
 }
 
diff --git a/src/modules/wasi.c b/src/modules/wasi.c
index ed5443b..0016b53 100644
--- a/src/modules/wasi.c
+++ b/src/modules/wasi.c
@@ -222,9 +222,8 @@ static ant_value_t wasi_handle_proc_exit(wasm_module_inst_t inst) {
 }
 
 static ant_value_t wasi_exported_func_call(ant_t *js, ant_value_t *args, int nargs) {
-  if (!js_check_native_tag(js->current_func, WASI_FUNC_TAG))
-    return js_mkerr(js, "Invalid WASI function");
   wasi_func_env_t *env = (wasi_func_env_t *)js_get_native(js->current_func, WASI_FUNC_TAG);
+  if (!env) return js_mkerr(js, "Invalid WASI function");
 
   uint32_t param_count = wasm_func_get_param_count(env->func, env->inst);
   uint32_t result_count = wasm_func_get_result_count(env->func, env->inst);
diff --git a/src/modules/wasm.c b/src/modules/wasm.c
index 8a41288..8fb2e77 100644
--- a/src/modules/wasm.c
+++ b/src/modules/wasm.c
@@ -178,13 +178,11 @@ static wasm_valkind_t wasm_valkind_from_string(const char *name, size_t len, boo
 
 static wasm_module_handle_t *wasm_module_handle(ant_value_t value) {
   if (!js_check_brand(value, BRAND_WASM_MODULE)) return NULL;
-  if (!js_check_native_tag(value, WASM_MODULE_NATIVE_TAG)) return NULL;
   return (wasm_module_handle_t *)js_get_native(value, WASM_MODULE_NATIVE_TAG);
 }
 
 static wasm_instance_handle_t *wasm_instance_handle(ant_value_t value) {
   if (!js_check_brand(value, BRAND_WASM_INSTANCE)) return NULL;
-  if (!js_check_native_tag(value, WASM_INSTANCE_NATIVE_TAG)) return NULL;
   return (wasm_instance_handle_t *)js_get_native(value, WASM_INSTANCE_NATIVE_TAG);
 }
 
@@ -195,7 +193,6 @@ static wasm_extern_handle_t *wasm_extern_handle(ant_value_t value, wasm_extern_w
     return NULL;
   }
 
-  if (!js_check_native_tag(value, WASM_EXTERN_NATIVE_TAG)) return NULL;
   wasm_extern_handle_t *handle = (wasm_extern_handle_t *)js_get_native(value, WASM_EXTERN_NATIVE_TAG);
   return handle && handle->kind == kind ? handle : NULL;
 }
@@ -323,8 +320,7 @@ static bool js_value_to_wasm(ant_t *js, ant_value_t value, wasm_valkind_t kind,
       }
       if (!is_callable(value)) return false;
       state = js_get_slot(value, SLOT_DATA);
-      if (!is_object_type(state) || !js_check_native_tag(state, WASM_FUNC_STATE_TAG))
-        return false;
+      if (!is_object_type(state)) return false;
       handle = (wasm_func_handle_t *)js_get_native(state, WASM_FUNC_STATE_TAG);
       if (!handle || !handle->func) return false;
       out->of.ref = wasm_func_as_ref(handle->func);
@@ -459,10 +455,9 @@ static ant_value_t js_wasm_exported_func_call(ant_t *js, ant_value_t *args, int
   wasm_func_handle_t *handle;
   wasm_func_t *func;
 
-  if (!is_object_type(state) || !js_check_native_tag(state, WASM_FUNC_STATE_TAG))
-    return js_mkerr(js, "Invalid WebAssembly function");
-
-  handle = (wasm_func_handle_t *)js_get_native(state, WASM_FUNC_STATE_TAG);
+  handle = is_object_type(state) 
+    ? (wasm_func_handle_t *)js_get_native(state, WASM_FUNC_STATE_TAG)
+    : NULL;
   func = handle ? handle->func : NULL;
   if (!func) return js_mkerr(js, "Invalid WebAssembly function");
 
@@ -1212,10 +1207,9 @@ static ant_value_t js_wasm_table_set(ant_t *js, ant_value_t *args, int nargs) {
       return js_mkerr_typed(js, JS_ERR_TYPE, "WebAssembly.Table.set expects a WebAssembly function or null");
     
     state = js_get_slot(args[1], SLOT_DATA);
-    if (!is_object_type(state) || !js_check_native_tag(state, WASM_FUNC_STATE_TAG))
-      return js_mkerr_typed(js, JS_ERR_TYPE, "WebAssembly.Table.set expects a WebAssembly function or null");
-    
-    func_handle = (wasm_func_handle_t *)js_get_native(state, WASM_FUNC_STATE_TAG);
+    func_handle = is_object_type(state)
+      ? (wasm_func_handle_t *)js_get_native(state, WASM_FUNC_STATE_TAG)
+      : NULL;
     if (!func_handle || !func_handle->func)
       return js_mkerr_typed(js, JS_ERR_TYPE, "WebAssembly.Table.set expects a WebAssembly function or null");
     
diff --git a/src/modules/worker_threads.c b/src/modules/worker_threads.c
index b15c037..b3e8e0d 100644
--- a/src/modules/worker_threads.c
+++ b/src/modules/worker_threads.c
@@ -93,7 +93,6 @@ static void wt_init_env_store(ant_t *js, bool is_worker) {
 
 static ant_worker_thread_t *wt_get_worker(ant_t *js, ant_value_t this_obj) {
   if (!is_object_type(this_obj)) return NULL;
-  if (!js_check_native_tag(this_obj, WORKER_NATIVE_TAG)) return NULL;
   return (ant_worker_thread_t *)js_get_native(this_obj, WORKER_NATIVE_TAG);
 }
 
diff --git a/src/modules/zlib.c b/src/modules/zlib.c
index 6d738f8..cf2d5de 100644
--- a/src/modules/zlib.c
+++ b/src/modules/zlib.c
@@ -75,7 +75,6 @@ static ant_value_t pick_callback(ant_value_t *args, int nargs) {
 }
 
 static zlib_stream_t *zlib_stream_ptr(ant_value_t obj) {
-  if (!js_check_native_tag(obj, ZLIB_STREAM_TAG)) return NULL;
   return (zlib_stream_t *)js_get_native(obj, ZLIB_STREAM_TAG);
 }
 
diff --git a/src/streams/codec.c b/src/streams/codec.c
index 3e083dc..55b44fe 100644
--- a/src/streams/codec.c
+++ b/src/streams/codec.c
@@ -84,9 +84,7 @@ static ant_value_t codec_flush_controller(ant_value_t *args, int nargs) {
 }
 
 static ant_value_t tes_transform(ant_t *js, ant_value_t *args, int nargs) {
-  tes_state_t *st = js_check_native_tag(js->current_func, TES_NATIVE_TAG)
-    ? (tes_state_t *)js_get_native(js->current_func, TES_NATIVE_TAG)
-    : NULL;
+  tes_state_t *st = (tes_state_t *)js_get_native(js->current_func, TES_NATIVE_TAG);
   
   if (!st) return js_mkerr_typed(js, JS_ERR_TYPE, "Invalid TextEncoderStream");
   ant_value_t ctrl_obj = codec_transform_controller(args, nargs);
@@ -171,9 +169,7 @@ static ant_value_t tes_transform(ant_t *js, ant_value_t *args, int nargs) {
 }
 
 static ant_value_t tes_flush(ant_t *js, ant_value_t *args, int nargs) {
-  tes_state_t *st = js_check_native_tag(js->current_func, TES_NATIVE_TAG)
-    ? (tes_state_t *)js_get_native(js->current_func, TES_NATIVE_TAG)
-    : NULL;
+  tes_state_t *st = (tes_state_t *)js_get_native(js->current_func, TES_NATIVE_TAG);
   
   if (!st) return js_mkerr_typed(js, JS_ERR_TYPE, "Invalid TextEncoderStream");
   ant_value_t ctrl_obj = codec_flush_controller(args, nargs);
@@ -247,9 +243,7 @@ static ant_value_t js_tes_ctor(ant_t *js, ant_value_t *args, int nargs) {
 }
 
 static ant_value_t tds_transform(ant_t *js, ant_value_t *args, int nargs) {
-  td_state_t *st = js_check_native_tag(js->current_func, TDS_NATIVE_TAG)
-    ? (td_state_t *)js_get_native(js->current_func, TDS_NATIVE_TAG)
-    : NULL;
+  td_state_t *st = (td_state_t *)js_get_native(js->current_func, TDS_NATIVE_TAG);
   
   if (!st) return js_mkerr_typed(js, JS_ERR_TYPE, "Invalid TextDecoderStream");
   ant_value_t ctrl_obj = codec_transform_controller(args, nargs);
@@ -276,9 +270,7 @@ static ant_value_t tds_transform(ant_t *js, ant_value_t *args, int nargs) {
 }
 
 static ant_value_t tds_flush(ant_t *js, ant_value_t *args, int nargs) {
-  td_state_t *st = js_check_native_tag(js->current_func, TDS_NATIVE_TAG)
-    ? (td_state_t *)js_get_native(js->current_func, TDS_NATIVE_TAG)
-    : NULL;
+  td_state_t *st = (td_state_t *)js_get_native(js->current_func, TDS_NATIVE_TAG);
   
   if (!st) return js_mkerr_typed(js, JS_ERR_TYPE, "Invalid TextDecoderStream");
   ant_value_t ctrl_obj = codec_flush_controller(args, nargs);
diff --git a/src/streams/compression.c b/src/streams/compression.c
index 5445903..aa7147a 100644
--- a/src/streams/compression.c
+++ b/src/streams/compression.c
@@ -106,10 +106,13 @@ static void zstate_inflate_finalize(ant_t *js, ant_object_t *obj) {
 
 static void brotli_state_finalize(ant_t *js, ant_object_t *obj) {
   ant_value_t value = js_obj_from_ptr(obj);
-  uint32_t tag = js_check_native_tag(value, CS_BROTLI_NATIVE_TAG) 
-    ? CS_BROTLI_NATIVE_TAG 
-    : DS_BROTLI_NATIVE_TAG;
+  uint32_t tag = CS_BROTLI_NATIVE_TAG;
   brotli_stream_state_t *st = (brotli_stream_state_t *)js_get_native(value, tag);
+  if (!st) {
+    tag = DS_BROTLI_NATIVE_TAG;
+    st = (brotli_stream_state_t *)js_get_native(value, tag);
+  }
+  if (!st) return;
   brotli_stream_state_destroy(st);
   js_clear_native(value, tag);
 }
diff --git a/src/streams/pipes.c b/src/streams/pipes.c
index 6512282..40b43b4 100644
--- a/src/streams/pipes.c
+++ b/src/streams/pipes.c
@@ -58,7 +58,6 @@ static void pipe_state_finalize(ant_t *js, ant_object_t *obj) {
 }
 
 static pipe_state_t *pipe_get_state(ant_value_t state) {
-  if (!js_check_native_tag(state, PIPE_STATE_NATIVE_TAG)) return NULL;
   return (pipe_state_t *)js_get_native(state, PIPE_STATE_NATIVE_TAG);
 }
 
@@ -494,7 +493,6 @@ static void tee_state_finalize(ant_t *js, ant_object_t *obj) {
 }
 
 static tee_state_t *tee_get_state(ant_value_t state) {
-  if (!js_check_native_tag(state, TEE_STATE_NATIVE_TAG)) return NULL;
   return (tee_state_t *)js_get_native(state, TEE_STATE_NATIVE_TAG);
 }
 
diff --git a/src/streams/readable.c b/src/streams/readable.c
index f9cb48a..d50a9a4 100644
--- a/src/streams/readable.c
+++ b/src/streams/readable.c
@@ -50,12 +50,10 @@ bool rs_stream_unusable(ant_value_t stream_obj) {
 }
 
 rs_stream_t *rs_get_stream(ant_value_t obj) {
-  if (!js_check_native_tag(obj, RS_STREAM_NATIVE_TAG)) return NULL;
   return (rs_stream_t *)js_get_native(obj, RS_STREAM_NATIVE_TAG);
 }
 
 rs_controller_t *rs_get_controller(ant_value_t obj) {
-  if (!js_check_native_tag(obj, RS_CONTROLLER_NATIVE_TAG)) return NULL;
   return (rs_controller_t *)js_get_native(obj, RS_CONTROLLER_NATIVE_TAG);
 }
 
diff --git a/src/streams/writable.c b/src/streams/writable.c
index 4996d34..50b506b 100644
--- a/src/streams/writable.c
+++ b/src/streams/writable.c
@@ -38,12 +38,10 @@ bool ws_is_controller(ant_value_t obj) {
 }
 
 ws_stream_t *ws_get_stream(ant_value_t obj) {
-  if (!js_check_native_tag(obj, WS_STREAM_NATIVE_TAG)) return NULL;
   return (ws_stream_t *)js_get_native(obj, WS_STREAM_NATIVE_TAG);
 }
 
 ws_controller_t *ws_get_controller(ant_value_t obj) {
-  if (!js_check_native_tag(obj, WS_CONTROLLER_NATIVE_TAG)) return NULL;
   return (ws_controller_t *)js_get_native(obj, WS_CONTROLLER_NATIVE_TAG);
 }