diff --git a/lib/libesp32/berry/default/be_modtab.c b/lib/libesp32/berry/default/be_modtab.c
index 73f8c29df..8275ec739 100644
--- a/lib/libesp32/berry/default/be_modtab.c
+++ b/lib/libesp32/berry/default/be_modtab.c
@@ -22,6 +22,7 @@ be_extern_native_module(gc);
 be_extern_native_module(solidify);
 be_extern_native_module(introspect);
 be_extern_native_module(strict);
+be_extern_native_module(undefined);
 
 /* Berry extensions */
 #include "be_mapping.h"
@@ -104,6 +105,7 @@ BERRY_LOCAL const bntvmodule* const be_module_table[] = {
 #if BE_USE_STRICT_MODULE
     &be_native_module(strict),
 #endif
+    &be_native_module(undefined),
 
     /* Berry extensions */
     &be_native_module(cb),
diff --git a/lib/libesp32/berry/generate/be_fixed_undefined.h b/lib/libesp32/berry/generate/be_fixed_undefined.h
new file mode 100644
index 000000000..ab36914dc
--- /dev/null
+++ b/lib/libesp32/berry/generate/be_fixed_undefined.h
@@ -0,0 +1,17 @@
+#include "be_constobj.h"
+
+static be_define_const_map_slots(m_libundefined_map) {
+    { be_const_key(_X2Ep, -1), be_const_nil() },
+};
+
+static be_define_const_map(
+    m_libundefined_map,
+    1
+);
+
+static be_define_const_module(
+    m_libundefined,
+    "undefined"
+);
+
+BE_EXPORT_VARIABLE be_define_const_native_module(undefined);
diff --git a/lib/libesp32/berry/src/be_class.c b/lib/libesp32/berry/src/be_class.c
index 0ad035150..225974aff 100644
--- a/lib/libesp32/berry/src/be_class.c
+++ b/lib/libesp32/berry/src/be_class.c
@@ -12,6 +12,7 @@
 #include "be_gc.h"
 #include "be_vm.h"
 #include "be_func.h"
+#include "be_module.h"
 #include <string.h>
 
 #define check_members(vm, c)            \
@@ -240,12 +241,6 @@ bbool be_class_newobj(bvm *vm, bclass *c, int pos, int argc, int mode)
     return bfalse;
 }
 
-/* Default empty constructor */
-static int default_init_native_method(bvm *vm)
-{
-    be_return_nil(vm);
-}
-
 /* Find instance member by name and copy value to `dst` */
 /* Do not look into virtual members */
 int be_instance_member_simple(bvm *vm, binstance *instance, bstring *name, bvalue *dst)
@@ -280,7 +275,7 @@ int be_instance_member(bvm *vm, binstance *instance, bstring *name, bvalue *dst)
     } else {  /* if no method found, try virtual */
         /* if 'init' does not exist, create a virtual empty constructor */
         if (strcmp(str(name), "init") == 0) {
-            var_setntvfunc(dst, default_init_native_method);
+            var_setntvfunc(dst, be_default_init_native_function);
             return var_primetype(dst);
         } else {
             /* get method 'member' */
@@ -297,10 +292,15 @@ int be_instance_member(bvm *vm, binstance *instance, bstring *name, bvalue *dst)
                     *dst = obj->members[dst->v.i];
                 }
                 type = var_type(dst);
-                if (type != BE_NIL) {
-                    var_clearstatic(dst);
-                    return type;
+                if (type == BE_MODULE) {
+                    /* check if the module is named `undefined` */
+                    bmodule *mod = var_toobj(dst);
+                    if (strcmp(be_module_name(mod), "undefined") == 0) {
+                        return BE_NONE;     /* if the return value is module `undefined`, consider it is an error */
+                    }
                 }
+                var_clearstatic(dst);
+                return type;
             }
         }
     }
diff --git a/lib/libesp32/berry/src/be_module.c b/lib/libesp32/berry/src/be_module.c
index e2b186e9a..935b89bb3 100644
--- a/lib/libesp32/berry/src/be_module.c
+++ b/lib/libesp32/berry/src/be_module.c
@@ -255,7 +255,7 @@ static void cache_module(bvm *vm, bstring *name)
     *v = vm->top[-1];
 }
 
-/* Try to run '()' function of module. Module is already loaded. */
+/* Try to run 'init(m)' function of module. Module is already loaded. */
 static void module_init(bvm *vm) {
     if (be_ismodule(vm, -1)) {
         if (be_getmember(vm, -1, "init")) {
@@ -318,6 +318,11 @@ int be_module_attr(bvm *vm, bmodule *module, bstring *attr, bvalue *dst)
 {
     bvalue *member = be_map_findstr(vm, module->table, attr);
     if (!member) {  /* try the 'member' function */
+        /* if 'init' does not exist, don't call member() */
+        if (strcmp(str(attr), "init") == 0) {
+            var_setntvfunc(dst, be_default_init_native_function);
+            return var_primetype(dst);
+        }
         member = be_map_findstr(vm, module->table, str_literal(vm, "member"));
         if (member && var_basetype(member) == BE_FUNCTION) {
             bvalue *top = vm->top;
@@ -327,9 +332,16 @@ int be_module_attr(bvm *vm, bmodule *module, bstring *attr, bvalue *dst)
             be_dofunc(vm, top, 1); /* call method 'method' */
             vm->top -= 2;
             *dst = *vm->top;   /* copy result to R(A) */
-            if (var_basetype(dst) != BE_NIL) {
-                return var_type(dst);
+            
+            int type = var_type(dst);
+            if (type == BE_MODULE) {
+                /* check if the module is named `undefined` */
+                bmodule *mod = var_toobj(dst);
+                if (strcmp(be_module_name(mod), "undefined") == 0) {
+                    return BE_NONE;     /* if the return value is module `undefined`, consider it is an error */
+                }
             }
+            return type;
         }
         return BE_NONE;
     }
diff --git a/lib/libesp32/berry/src/be_undefinedlib.c b/lib/libesp32/berry/src/be_undefinedlib.c
new file mode 100644
index 000000000..7e5ce4495
--- /dev/null
+++ b/lib/libesp32/berry/src/be_undefinedlib.c
@@ -0,0 +1,34 @@
+/********************************************************************
+** Copyright (c) 2018-2020 Guan Wenliang, Stephan Hadinger
+** This file is part of the Berry default interpreter.
+** skiars@qq.com, https://github.com/Skiars/berry
+** See Copyright Notice in the LICENSE file or at
+** https://github.com/Skiars/berry/blob/master/LICENSE
+********************************************************************/
+#include "be_object.h"
+#include "be_module.h"
+#include "be_string.h"
+#include "be_vector.h"
+#include "be_class.h"
+#include "be_debug.h"
+#include "be_map.h"
+#include "be_vm.h"
+#include "be_exec.h"
+#include "be_gc.h"
+#include <string.h>
+
+
+#if !BE_USE_PRECOMPILED_OBJECT
+be_native_module_attr_table(undefined) {
+    be_native_module_nil(".p"),         /* not needed but can't be empty */
+};
+
+be_define_native_module(undefined, NULL);
+#else
+/* @const_object_info_begin
+module undefined (scope: global) {
+    .p, nil()
+}
+@const_object_info_end */
+#include "../generate/be_fixed_undefined.h"
+#endif
diff --git a/lib/libesp32/berry/src/be_vm.c b/lib/libesp32/berry/src/be_vm.c
index c60d88c01..2b6113909 100644
--- a/lib/libesp32/berry/src/be_vm.c
+++ b/lib/libesp32/berry/src/be_vm.c
@@ -1291,6 +1291,18 @@ void be_dofunc(bvm *vm, bvalue *v, int argc)
     }
 }
 
+/* Default empty constructor */
+int be_default_init_native_function(bvm *vm)
+{
+    int argc = be_top(vm);
+    if (argc >= 1) {
+        be_pushvalue(vm, 1);
+    } else {
+        be_pushnil(vm);
+    }
+    be_return(vm);
+}
+
 BERRY_API void be_set_obs_hook(bvm *vm, bobshook hook)
 {
     (void)vm;       /* avoid comiler warning */
diff --git a/lib/libesp32/berry/src/be_vm.h b/lib/libesp32/berry/src/be_vm.h
index a2427277a..17a21b6c6 100644
--- a/lib/libesp32/berry/src/be_vm.h
+++ b/lib/libesp32/berry/src/be_vm.h
@@ -128,6 +128,7 @@ struct bvm {
 #define BASE_FRAME          (1 << 0)
 #define PRIM_FUNC           (1 << 1)
 
+int be_default_init_native_function(bvm *vm);
 void be_dofunc(bvm *vm, bvalue *v, int argc);
 bbool be_value2bool(bvm *vm, bvalue *v);
 bbool be_vm_iseq(bvm *vm, bvalue *a, bvalue *b);
diff --git a/lib/libesp32/berry_mapping/src/be_const_members.c b/lib/libesp32/berry_mapping/src/be_const_members.c
index 810de4574..01a7b322c 100644
--- a/lib/libesp32/berry_mapping/src/be_const_members.c
+++ b/lib/libesp32/berry_mapping/src/be_const_members.c
@@ -99,6 +99,20 @@ bbool be_const_module_member(bvm *vm, const be_const_member_t * definitions, siz
   return be_const_member_dual(vm, definitions, def_len, bfalse);   // call for module, non-method
 }
 
+/* This version raises an exception if the attribute is not found */
+void be_const_module_member_raise(bvm *vm, const be_const_member_t * definitions, size_t def_len) {
+  if (!be_const_member_dual(vm, definitions, def_len, bfalse)) {
+    be_module_load(vm, be_newstr(vm, "undefined"));
+  }
+}
+
 bbool be_const_class_member(bvm *vm, const be_const_member_t * definitions, size_t def_len) {
   return be_const_member_dual(vm, definitions, def_len, btrue);   // call for method
 }
+
+/* This version raises an exception if the attribute is not found */
+void be_const_class_member_raise(bvm *vm, const be_const_member_t * definitions, size_t def_len) {
+  if (!be_const_member_dual(vm, definitions, def_len, btrue)) {
+    be_module_load(vm, be_newstr(vm, "undefined"));
+  }
+}
diff --git a/lib/libesp32/berry_mapping/src/be_mapping.h b/lib/libesp32/berry_mapping/src/be_mapping.h
index 01aa2e17f..0b0ef2c1e 100644
--- a/lib/libesp32/berry_mapping/src/be_mapping.h
+++ b/lib/libesp32/berry_mapping/src/be_mapping.h
@@ -100,7 +100,9 @@ extern void be_create_class_wrapper(bvm *vm, const char * class_name, void * ptr
 extern int be_find_global_or_module_member(bvm *vm, const char * cl_name);
 
 extern bbool be_const_module_member(bvm *vm, const be_const_member_t * definitions, size_t def_len);
+extern void be_const_module_member_raise(bvm *vm, const be_const_member_t * definitions, size_t def_len);  /* raise an exception if not found */
 extern bbool be_const_class_member(bvm *vm, const be_const_member_t * definitions, size_t def_len);
+extern void be_const_class_member_raise(bvm *vm, const be_const_member_t * definitions, size_t def_len);  /* raise an exception if not found */
 extern intptr_t be_convert_single_elt(bvm *vm, int idx, const char * arg_type, int *len);
 extern int be_check_arg_type(bvm *vm, int arg_start, int argc, const char * arg_type, intptr_t p[8]);
 extern int be_call_c_func(bvm *vm, const void * func, const char * return_type, const char * arg_type);
diff --git a/lib/libesp32/berry_tasmota/src/be_ctypes.c b/lib/libesp32/berry_tasmota/src/be_ctypes.c
index 7ebe74310..cd7650d41 100644
--- a/lib/libesp32/berry_tasmota/src/be_ctypes.c
+++ b/lib/libesp32/berry_tasmota/src/be_ctypes.c
@@ -264,8 +264,8 @@ int be_ctypes_member(bvm *vm) {
         }
         be_return(vm);
     }
-
-    be_return_nil(vm);
+    be_module_load(vm, be_newstr(vm, "undefined"));
+    be_return(vm);
 }
 
 // setmember takes 3 arguments:
diff --git a/lib/libesp32/berry_tasmota/src/be_light_state_class.cpp b/lib/libesp32/berry_tasmota/src/be_light_state_class.cpp
index 8c0782ace..5c278dd2d 100644
--- a/lib/libesp32/berry_tasmota/src/be_light_state_class.cpp
+++ b/lib/libesp32/berry_tasmota/src/be_light_state_class.cpp
@@ -70,11 +70,8 @@ const be_const_member_t light_state_members[] = {
 extern "C" int light_state_get(bvm *vm);
 
 static int light_state_member(bvm *vm) {
-  if (be_const_class_member(vm, light_state_members, ARRAY_SIZE(light_state_members))) {
-    be_return(vm);
-  } else {
-    be_return_nil(vm);
-  }
+  be_const_class_member_raise(vm, light_state_members, ARRAY_SIZE(light_state_members));
+  be_return(vm);
 }
 
 #include "be_fixed_be_class_light_state.h"
diff --git a/lib/libesp32/berry_tasmota/src/be_zigbee.c b/lib/libesp32/berry_tasmota/src/be_zigbee.c
index d0ae432cc..a7efdfa25 100644
--- a/lib/libesp32/berry_tasmota/src/be_zigbee.c
+++ b/lib/libesp32/berry_tasmota/src/be_zigbee.c
@@ -45,11 +45,8 @@ const be_const_member_t zd_members[] = {
 };
 
 static int zd_member(bvm *vm) {
-  if (be_const_class_member(vm, zd_members, ARRAY_SIZE(zd_members))) {
-    be_return(vm);
-  } else {
-    be_return_nil(vm);
-  }
+  be_const_class_member_raise(vm, zd_members, ARRAY_SIZE(zd_members));
+  be_return(vm);
 }
 
 extern int zc_info(struct bvm *vm);
diff --git a/lib/libesp32/berry_tasmota/src/embedded/persist.be b/lib/libesp32/berry_tasmota/src/embedded/persist.be
index 164a1dd7b..9a1dbbb84 100644
--- a/lib/libesp32/berry_tasmota/src/embedded/persist.be
+++ b/lib/libesp32/berry_tasmota/src/embedded/persist.be
@@ -30,7 +30,7 @@ persist_module.init = def (m)
       # print("Persist init")
     end
 
-    #- virtual member getter, if a key does not exists return `nil`-#
+    #- virtual member getter, if a key does not exists return `nil` instead of exception -#
     def member(key)
       return self._p.find(key)
     end
diff --git a/lib/libesp32_lvgl/lv_binding_berry/src/lv_berry.c b/lib/libesp32_lvgl/lv_binding_berry/src/lv_berry.c
index 879c33f55..745e550c5 100644
--- a/lib/libesp32_lvgl/lv_binding_berry/src/lv_berry.c
+++ b/lib/libesp32_lvgl/lv_binding_berry/src/lv_berry.c
@@ -334,5 +334,6 @@ int lv0_member(bvm *vm) {
       be_return(vm);
     }
   }
-  be_return_nil(vm);
+  be_module_load(vm, be_newstr(vm, "undefined"));
+  be_return(vm);
 }
diff --git a/tasmota/berry/modules/ctypes.be b/tasmota/berry/modules/ctypes.be
deleted file mode 100644
index b6a0607df..000000000
--- a/tasmota/berry/modules/ctypes.be
+++ /dev/null
@@ -1,629 +0,0 @@
-#-------------------------------------------------------------
-#- Ctypes for Berry
-#-
-#- Inspired from Python's ctypes structure
-#-------------------------------------------------------------#
-import string
- 
-ctypes = module('ctypes')
-
-#-------------------------------------------------------------
-#- Basic types for mapping
-#-
-#- ints of size 1/2/4 bytes (little endian by default)
-#- usigned ints of size 1/2/4 bytes (little endian by default)
-#-
-#- (Big Endian are negative numbers)
-#-------------------------------------------------------------#
-
-# default is little_endian
-ctypes.i32    = 14
-ctypes.i16    = 12
-ctypes.i8     = 11
-ctypes.u32    =  4
-ctypes.u16    =  2
-ctypes.u8     =  1
-
-# explicit little endian
-ctypes.le_i32 = 14
-ctypes.le_i16 = 12
-ctypes.le_i8  = 11
-ctypes.le_u32 =  4
-ctypes.le_u16 =  2
-ctypes.le_u8  =  1
-
-# big endian
-ctypes.be_i32 = -14
-ctypes.be_i16 = -12
-ctypes.be_i8  = -11
-ctypes.be_u32 =  -4
-ctypes.be_u16 =  -2
-ctypes.be_u8  =  -1
-
-# floating point
-ctypes.float  = 5
-ctypes.double = 10
-
-# pointer
-ctypes.ptr32  =  9
-ctypes.ptr64  = -9
-
-ctypes.bf_x   = 0 # generic bitfield
-# bitfields (always unsigned)
-ctypes.bf_0   = 100 # serves as base
-ctypes.bf_1   = 101
-ctypes.bf_2   = 102
-ctypes.bf_3   = 103
-ctypes.bf_4   = 104
-ctypes.bf_5   = 105
-ctypes.bf_6   = 106
-ctypes.bf_7   = 107
-ctypes.bf_8   = 108
-ctypes.bf_9   = 109
-ctypes.bf_10  = 110
-ctypes.bf_11  = 111
-ctypes.bf_12  = 112
-ctypes.bf_13  = 113
-ctypes.bf_14  = 114
-ctypes.bf_15  = 115
-ctypes.bf_16  = 116
-
-ctypes.type_mapping = {
-  14: "ctypes_i32",
-  12: "ctypes_i16",
-  11: "ctypes_i8",
-   4: "ctypes_u32",
-   2: "ctypes_u16",
-   1: "ctypes_u8",
-
-  -14:"ctypes_be_i32",  # big endian
-  -12:"ctypes_be_i16",
-  -11:"ctypes_be_i8",
-  -4: "ctypes_be_u32",
-  -2: "ctypes_be_u16",
-  -1: "ctypes_be_u8",
-
-   5: "ctypes_float",
-  10: "ctypes_double",
-   9: "ctypes_ptr32",
-  -9: "ctypes_ptr64",
-
-   0: "ctypes_bf"       # bitfield
-}
-
-ctypes.type_to_str = def (type_num)
-  var type_name = ctypes.type_mapping.find(type_num)
-  if type_name == nil
-    return str(type_num)
-  end
-  return type_name
-end
-
-def findinlist(l, x)
-  for i:0..size(l)-1
-    if l[i] == x
-      return i
-    end
-  end
-end
-
-#-------------------------------------------------------------
-#- 'get_bits' function
-#-
-#- Reads a bit-field in a `bytes()` object
-#-
-#- Input:
-#-   b: bytes() object to read from
-#-   offset_bytes (int): byte offset in the bytes() object
-#-   offset_bits  (int): bit number to start reading from (0 = LSB)
-#-   len_bits     (int): how many bits to read
-#- Output:
-#-   valuer (int)
-#-------------------------------------------------------------#
-ctypes.get_bits = def (b, offset_bytes, offset_bits, len_bits)
-  if !isinstance(b, bytes) raise "value_error", "first argument must be of type 'bytes'" end
-  if offset_bits < 0 || offset_bits > 7 raise "value_error", "offset_bits must be between 0 and 7" end
-  if len_bits <= 0 || len_bits > 32 raise "value_error", "length in bits must be between 0 and 32" end
-  var ret = 0
-
-  var bit_shift = 0                   # bit number to write to
-
-  while (len_bits > 0)
-    var block_bits = 8 - offset_bits    # how many bits to read in the current block (block = byte)
-    if block_bits > len_bits  block_bits = len_bits end
-
-    var mask = ( (1<<block_bits) - 1) << offset_bits
-    # print(string.format("mask = %02X", mask))
-    ret = ret | ( ((b[offset_bytes] & mask) >> offset_bits) << bit_shift)
-
-    # move the input window
-    bit_shift += block_bits
-    len_bits -= block_bits
-    offset_bits = 0                   # start at full next byte
-    offset_bytes += 1
-  end
-
-  return ret
-end
-
-ctypes.sort = def (l)
-  # insertion sort
-  for i:1..size(l)-1
-    var k = l[i]
-    var j = i
-    while (j > 0) && (l[j-1] > k)
-      l[j] = l[j-1]
-      j -= 1
-    end
-    l[j] = k
-  end
-  return l
-end
-
-#-------------------------------------------------------------
-#- 'set_bits' function
-#-
-#- Writes a bit-field in a `bytes()` object
-#-
-#- Input:
-#-   b: bytes() object to write to
-#-   offset_bytes (int): byte offset in the bytes() object
-#-   offset_bits  (int): bit number to start writing to (0 = LSB)
-#-   len_bits     (int): how many bits to write
-#- Output:
-#-   bytes() object modified (by reference)
-#-------------------------------------------------------------#
-ctypes.set_bits = def (b, offset_bytes, offset_bits, len_bits, val)
-  if !isinstance(b, bytes) raise "value_error", "first argument must be of type 'bytes'" end
-  if offset_bits < 0 || offset_bits > 7 raise "value_error", "offset_bits must be between 0 and 7" end
-  if len_bits <= 0 || len_bits > 32 raise "value_error", "length in bits must be between 0 and 32" end
-
-  while (len_bits > 0)
-    var block_bits = 8 - offset_bits    # how many bits to write in the current block (block = byte)
-    if block_bits > len_bits  block_bits = len_bits end
-
-    var mask_val = (1<<block_bits) - 1  # mask to the n bits to get for this block
-    var mask_b_inv = 0xFF - (mask_val << offset_bits)
-    b[offset_bytes] = (b[offset_bytes] & mask_b_inv) | ((val & mask_val) << offset_bits)
-
-    # move the input window
-    val >>= block_bits
-    len_bits -= block_bits
-    offset_bits = 0                   # start at full next byte
-    offset_bytes += 1
-  end
-  return b
-end
-
-
-#- print the C types -#1
-ctypes.print_types = def ()
-  print("/********************************************************************")
-  print(" * Generated code, don't edit")
-  print(" *******************************************************************/")
-  print()
-  print("static const char * be_ctypes_instance_mappings[];    /* forward definition */")
-  print()
-end
-
-global_classes = []   # track the list of all classes and
-global_mappings = []  # mapping to Berry classes, ex: lv_color
-
-ctypes.print_classes = def (module_name)
-  # print mappings
-  if size(global_mappings) > 7
-    raise "internal_error", "too many mappings, 7 max"
-  end
-  print("static const char * be_ctypes_instance_mappings[] = {")
-  for n:global_mappings.iter()
-    print(string.format("  \"%s\",", n))
-  end
-  print("  NULL")
-  print("};")
-  print()
-
-  ctypes.sort(global_classes)
-
-  for elt:global_classes
-    print(string.format("static be_define_ctypes_class(%s, &be_%s, &be_class_ctypes_bytes, \"%s\");", elt, elt, elt))
-  end
-
-  print()
-  print(string.format("void be_load_ctypes_%s_definitions_lib(bvm *vm) {", module_name))
-  for elt:global_classes
-    print(string.format("  ctypes_register_class(vm, &be_class_%s);", elt))
-  end
-  print("}")
-  print()
-  print("be_ctypes_class_by_name_t be_ctypes_lvgl_classes[] = {")
-  for elt:global_classes
-    print(string.format("  { \"%s\", &be_class_%s },", elt, elt))
-  end
-  print("};")
-  print("const size_t be_ctypes_lvgl_classes_size = sizeof(be_ctypes_lvgl_classes)/sizeof(be_ctypes_lvgl_classes[0]);")
-  print()
-
-  print("/********************************************************************/")
-  print()
-end
-
-#-------------------------------------------------------------
-#- 'ctypes.structure' class
-#-
-#- Parses a ctypes structure descriptor and creates
-#- a set of getters and setters
-#-
-#-------------------------------------------------------------#
-class structure
-  var cur_offset      # offset in bytes from buffer start
-  var bit_offset      # are we intra-byte?
-  var get_closures    #
-  var set_closures    #
-  var size_bytes      # size in bytes
-  var mapping         # map to generate C binding
-
-  # init world
-  def init(mapping, name)
-    self.cur_offset = 0
-    self.bit_offset = 0
-    self.size_bytes = 0           # overall size in bytes
-    self.get_closures = {}
-    self.set_closures = {}
-    self.mapping = {}
-
-    # parse mapping
-    self.parse_mapping(mapping, name)
-  end
-  #- iteratively parse mapping
-  #-
-  #- if name is not nil, it also outputs a C structure for the mapping
-  #-
-  #-------------------------------------------------------------#
-  def parse_mapping(mapping, name)
-    for map_line: mapping
-      self.parse_line(map_line)
-    end
-
-    # clear any outstanding bitfield
-    self.align(1)
-    self.size_bytes = self.cur_offset
-
-    if name != nil
-      var size_aligned =  self.size_bytes
-      # as a final structure, we align to 2/4 bytesboundaries
-      if size_aligned >= 3
-        size_aligned = ((size_aligned + 3)/4)*4
-      end
-
-      print(string.format("const be_ctypes_structure_t be_%s = {", name))
-      print(string.format("  %i,  /* size in bytes */", size_aligned))
-      print(string.format("  %i,  /* number of elements */", size(self.mapping)))
-      print(string.format("  be_ctypes_instance_mappings,"))
-      print(string.format("  (const be_ctypes_structure_item_t[%i]) {", size(self.mapping)))
-      # list keys for future binary search
-      var names = []
-      for n:self.mapping.keys() names.push(n) end   # convert to list
-      ctypes.sort(names)
-      for n:names
-        var args = self.mapping[n]
-        print(string.format("    { \"%s\", %i, %i, %i, %s, %i },", n, args[0], args[1], args[2], ctypes.type_to_str(args[3]), args[4]))
-      end
-      print("}};")
-      print()
-
-      # retain class definition
-      global_classes.push(name)
-    end
-  end
-
-  def size()
-    return self.size_bytes
-  end
-
-  # parse a single line
-  def parse_line(map_line)
-    var type_obj = map_line[0]
-    var name = map_line[1]
-    var bits = 0
-    if size(map_line) >= 3   bits = map_line[2] end
-
-    if isinstance(type_obj, ctypes.structure)
-      # nested structure
-      self.nested(name, type_obj)
-    end
-
-    var mapping_idx = 0   # mapping starts at 1
-    if isinstance(type_obj, list)
-      # it may be a list to denote a mapping to an instance
-      var mapping_name = type_obj[1]
-      if findinlist(global_mappings, mapping_name) == nil
-        global_mappings.push(mapping_name)
-      end
-      mapping_idx = findinlist(global_mappings, mapping_name) + 1
-
-      type_obj = type_obj[0]  # take the simple value of first element in the list
-    end
-
-    if type(type_obj) == 'int'
-      # simple attibute
-      # TODO check actual type
-      if type_obj > ctypes.bf_0
-        # bit field
-        self.get_bitfield_closure(name, type_obj - ctypes.bf_0, mapping_idx)
-      elif (type_obj == ctypes.ptr32) || (type_obj == ctypes.ptr64)
-        # pointer
-        self.get_ptr_closure(name, type_obj, mapping_idx)
-      elif (type_obj == ctypes.float) || (type_obj == ctypes.double)
-        # multi-bytes
-        self.get_float_closure(name, type_obj, mapping_idx)
-      else
-        # multi-bytes
-        self.get_int_closure(name, type_obj, mapping_idx)
-      end
-    end
-  end
-
-  #- ensure alignment to 1/2/4 bytes -#
-  def align(n)
-    if n != 1 && n != 2 && n != 4 raise "value_error", "acceptable values are 1/2/4" end
-
-    #- align to byte boundary if we're in a bitfield -#
-    if self.bit_offset != 0
-      #- we are not byte aligned, let's re-aling -#
-      self.cur_offset += 1
-      self.bit_offset = 0
-    end
-
-    #- check 2/4 bytes alignment -#
-    if self.cur_offset % n != 0
-      # we are not aligned with current size
-      self.cur_offset += n - self.cur_offset % n
-    end
-  end
-
-  def nested(name, type_obj)
-    var sub_size = type_obj.size()
-    if sub_size <= 0 raise "value_error", "empty sub-structure not supported" end
-
-    # align to appropriate sub-size
-    var align_size = sub_size
-    if align_size == 3 || align_size > 4  align_size = 4 end
-    self.align(align_size)
-
-    var offset = self.cur_offset    # var for closure
-
-    # include nested
-    for subname:type_obj.mapping.keys()
-      var val = type_obj.mapping[subname]
-      self.mapping[name+"_"+subname] = [val[0] + offset, val[1], val[2], val[3], val[4]]
-    end
-    # self.mapping[name] = [offset << 3, sub_size << 3]
-
-    self.get_closures[name] = def (b, p) return ctypes.nested_buffer(type_obj, offset + p, b) end
-    # self.set_closures[name] = def (b, p, v) return ctypes.nested_buffer(type_obj, offset + p, b) end
-
-    self.cur_offset += sub_size
-  end
-
-  def get_int_closure(name, type, instance_mapping)  # can be 1/2/4
-    #- abs size -#
-    var size_in_bytes = type < 0 ? - type : type
-    var signed = size_in_bytes > 10
-    var size_in_bytes_le_be = type % 10  # remove sign marker
-    size_in_bytes = size_in_bytes % 10  # remove sign marker
-
-    self.align(size_in_bytes)       # force alignment
-    var offset = self.cur_offset    # prepare variable for capture in closure
-    
-    self.mapping[name] = [offset, 0, 0, type, instance_mapping]
-
-    #- add closures -#
-    if signed
-      self.get_closures[name] = def (b, p) return b.geti(offset + p, size_in_bytes_le_be) end
-    else
-      self.get_closures[name] = def (b, p) return b.get(offset + p, size_in_bytes_le_be) end
-    end
-    self.set_closures[name] = def (b, p, v) return b.set(offset+ p, v, size_in_bytes_le_be) end
-    
-    self.cur_offset += size_in_bytes    # next offset
-  end
-
-  def get_ptr_closure(name, type, instance_mapping)  # can be 1/2/4
-    #- actual size -#
-    import introspect
-    var size_in_bytes = (type == ctypes.ptr32) ? 4 : 8
-
-    self.align(size_in_bytes)       # force alignment
-    var offset = self.cur_offset    # prepare variable for capture in closure
-    
-    self.mapping[name] = [offset, 0, 0, type, instance_mapping]
-
-    #- add closures -#
-    # TODO no closure yet, anyways need to rethink closures, they are too heavy
-    # if signed
-    #   self.get_closures[name] = def (b, p) return b.geti(offset + p, size_in_bytes_le_be) end
-    # else
-    #   self.get_closures[name] = def (b, p) return b.get(offset + p, size_in_bytes_le_be) end
-    # end
-    # self.set_closures[name] = def (b, p, v) return b.set(offset+ p, v, size_in_bytes_le_be) end
-    
-    self.cur_offset += size_in_bytes    # next offset
-  end
-
-  def get_float_closure(name, type, instance_mapping)  # can be 1/2/4
-    #- actual size -#
-    var size_in_bytes = (type == ctypes.float) ? 4 : 8
-
-    self.align(size_in_bytes)       # force alignment
-    var offset = self.cur_offset    # prepare variable for capture in closure
-    
-    self.mapping[name] = [offset, 0, 0, type, instance_mapping]
-
-    #- add closures -#
-    # TODO no closure yet, anyways need to rethink closures, they are too heavy
-    # if signed
-    #   self.get_closures[name] = def (b, p) return b.geti(offset + p, size_in_bytes_le_be) end
-    # else
-    #   self.get_closures[name] = def (b, p) return b.get(offset + p, size_in_bytes_le_be) end
-    # end
-    # self.set_closures[name] = def (b, p, v) return b.set(offset+ p, v, size_in_bytes_le_be) end
-    
-    self.cur_offset += size_in_bytes    # next offset
-  end
-
-  def get_bitfield_closure(name, size_in_bits, instance_mapping)  # can be 1..32
-    var cur_offset = self.cur_offset    # prepare variable for capture in closure
-    var bit_offset = self.bit_offset
-    self.mapping[name] = [cur_offset, bit_offset, size_in_bits, 0, instance_mapping]
-    self.get_closures[name] = def (b, p) return ctypes.get_bits(b, cur_offset + p, bit_offset, size_in_bits) end
-    self.set_closures[name] = def (b, p, v) return ctypes.set_bits(b, cur_offset+ p, bit_offset, size_in_bits, v) end
-
-    self.cur_offset += (self.bit_offset + size_in_bits) / 8
-    self.bit_offset = (self.bit_offset + size_in_bits) % 8
-  end
-end
-
-ctypes.structure = structure
-
-#-------------------------------------------------------------
-#- Structured buffer
-#-
-#- Inspired from Python's ctypes structure
-#-
-#- This class is a wrapper around `bytes()` object (actually a subclass)
-#- providing virtual members mapped to the ctypes structure.
-#-
-#- Takes as argument a ctypes.structure and an optional bytes() object
-#-------------------------------------------------------------#
-class buffer : bytes
-  var _cs                   # ctypes_structure associated
-
-  def init(cs, b)
-    if !isinstance(cs, ctypes.structure) raise "value_error", "first argument must be an instance of 'ctypes.structure'" end
-    self._cs = cs
-    var size = self._cs.size()    # size in bytes of the structure
-
-    super(self, bytes).init(size) # init bytes object with reserved size in memory
-
-    if isinstance(b, bytes)
-        self..b
-    end
-    self.resize(size)    # size once for all to the target size and complete with 00s
-  end
-
-  # accessor for virtual member
-  def member(name)
-    return self._cs.get_closures[name](self, 0)
-  end
-
-  # setter for virtual member
-  def setmember(name, value)
-    self._cs.set_closures[name](self, 0, value)
-  end
-end
-ctypes.buffer = buffer
-
-#-------------------------------------------------------------
-#- Nested buffer
-#-
-#- Nested structures are just pointers to the master bytes() object
-#-------------------------------------------------------------#
-class nested_buffer
-  var _cs             # ctypes.structure instance for this buffer
-  var _offset         # offset un bytes() to the structure
-  var _bytes          # reference to the overall buffer (by reference)
-  
-  def init(cs, offset, b)
-    if !isinstance(cs, ctypes.structure) raise "value_error", "first argument must be an instance of 'ctypes.structure'" end
-    if type(offset) != 'int' raise "value_error", "second argument must be of type 'int'" end
-    if !isinstance(b, bytes) raise "value_error", "third argument must be an instance of 'bytes'" end
-    self._cs = cs
-    self._offset = offset
-    self._bytes = b
-  end
-
-  # accessor for virtual member
-  def member(name)
-    return self._cs.get_closures[name](self._bytes, self._offset)
-  end
-
-  # setter for virtual member
-  def setmember(name, value)
-    self._cs.set_closures[name](self._bytes, self._offset, value)
-  end
-
-  def tostring()
-    return self._bytes[self._offset..self._offset+self._cs.size()-1].tostring()
-  end
-end
-ctypes.nested_buffer = nested_buffer
-
-
-return ctypes
-
-# ex = [
-#   [ctypes.u32, "a"],
-#   [ctypes.u16, "b"],
-#   [ctypes.i8,  "c"],
-#   [ctypes.i32, "d"],   # should infer an empty byte
-# ]
-
-# cs = ctypes.structure(ex)
-# bb = ctypes.buffer(cs, bytes("aabb"))
-
-# fa = cp.get_int_closure('a', 4)
-# fb = cp.get_int_closure('b', 2)
-# fc = cp.get_int_closure('c', 1)
-# fd = cp.get_int_closure('d', 4)
-
-# b = bytes("04030201AA55FFFF00010001")
-
-# cp.get_closures['a'](b)
-# cp.get_closures['b'](b)
-# cp.get_closures['c'](b)
-# cp.get_closures['d'](b)
-
-# bb = ctypes_buffer(cp, b)
-
-# bb.a = 0x11223344
-# bb
-# bb.a
-
-
-# > bb = ctypes_buffer(cp, b)
-# > bb.a
-# 16909060
-# > bb.b
-# 21930
-# > bb.c
-# 255
-# > bb.d
-# 16777472
-# > bb.e
-# key_error: e
-# stack traceback:
-#   <native>: in native function
-#   stdin:11: in function `member`
-#   stdin:1: in function `main`
-
-
-# > bb['a']
-# 16909060
-# > bb['b']
-# 21930
-# > bb['c']
-# 255
-# > bb['d']
-# 16777472
-
-#-
-> fa(b)
-16909060
-> fb(b)
-21930
-> fc(b)
-255
-> fd(b)
-16777472
-
--#
diff --git a/tasmota/tasmota_xdrv_driver/xdrv_52_3_berry_gpio.ino b/tasmota/tasmota_xdrv_driver/xdrv_52_3_berry_gpio.ino
index bd972e00f..3b616895e 100644
--- a/tasmota/tasmota_xdrv_driver/xdrv_52_3_berry_gpio.ino
+++ b/tasmota/tasmota_xdrv_driver/xdrv_52_3_berry_gpio.ino
@@ -40,11 +40,8 @@ extern "C" {
   // virtual member
   int gp_member(bvm *vm);
   int gp_member(bvm *vm) {
-    if (be_const_module_member(vm, lv_gpio_constants, lv_gpio_constants_size)) {
-      be_return(vm);
-    } else {
-      be_return_nil(vm);
-    }
+    be_const_module_member_raise(vm, lv_gpio_constants, lv_gpio_constants_size);
+    be_return(vm);
   }
 
   int gp_pin_mode(bvm *vm);
diff --git a/tasmota/tasmota_xdrv_driver/xdrv_52_3_berry_webserver.ino b/tasmota/tasmota_xdrv_driver/xdrv_52_3_berry_webserver.ino
index d2d1a2077..dd4e8384e 100644
--- a/tasmota/tasmota_xdrv_driver/xdrv_52_3_berry_webserver.ino
+++ b/tasmota/tasmota_xdrv_driver/xdrv_52_3_berry_webserver.ino
@@ -57,12 +57,10 @@ extern "C" {
         // we did have a match, low == high
         be_pushint(vm, webserver_constants[constant_idx].value);
         be_return(vm);
-      } else if (strcmp(needle, "init")) {
-        /* don't throw an exception if the 'init' function is requested */
-        be_raise(vm, "attribute_error", be_pushfstring(vm, "module 'webserver' has no such attribute '%s'", needle));
       }
     }
-    be_return_nil(vm);
+    be_module_load(vm, be_newstr(vm, "undefined"));
+    be_return(vm);
   }
 }