diff --git a/src/defs.h b/src/defs.h
index c9ddbc6..a5196d4 100644
--- a/src/defs.h
+++ b/src/defs.h
@@ -26,7 +26,6 @@ Useful for minimizing changes to implementation files between targets e.g. GDExt
   #define PRINT_ERROR(message) print_error("Godot Wasm: " + String(message))
   #define godot_error Error
   #define INSTANCE_FROM_ID(id) ObjectDB::get_instance(id)
-  #define INSTANCE_VALIDATE(id) VariantUtilityFunctions::is_instance_valid(id)
   #define REGISTRATION_METHOD _bind_methods
   #define RANDOM_BYTES(n) Crypto::create()->generate_random_bytes(n)
 #else
@@ -34,7 +33,6 @@ Useful for minimizing changes to implementation files between targets e.g. GDExt
   #define PRINT_ERROR(message) _err_print_error(__FUNCTION__, __FILE__, __LINE__, "Godot Wasm: " + String(message))
   #define godot_error Error
   #define INSTANCE_FROM_ID(id) ObjectDB::get_instance(id)
-  #define INSTANCE_VALIDATE(id) UtilityFunctions::is_instance_valid(id)
   #define REGISTRATION_METHOD _bind_methods
   #define RANDOM_BYTES(n) [n]()->PackedByteArray{Ref<Crypto> c;c.instantiate();return c->generate_random_bytes(n);}()
 #endif
@@ -47,5 +45,6 @@ Useful for minimizing changes to implementation files between targets e.g. GDExt
 #define TIME_MONOTONIC Time::get_singleton()->get_ticks_usec() * 1000
 #define NULL_VARIANT Variant()
 #define PAGE_SIZE 65536
+#define GODOT_WASM_EXTERNREF 128 // Different enums in Wasmer & Wasmtime (see https://github.com/wasmerio/wasmer/issues/5082)
 
 #endif
diff --git a/src/wasm.cpp b/src/wasm.cpp
index 77f18b6..900c9e7 100644
--- a/src/wasm.cpp
+++ b/src/wasm.cpp
@@ -55,7 +55,7 @@ namespace godot {
     inline wasm_val_t error_value(const char* message) {
       PRINT_ERROR(message);
       wasm_val_t value;
-      value.kind = WASM_ANYREF;
+      value.kind = GODOT_WASM_EXTERNREF;
       value.of.ref = NULL;
       return value;
     }
@@ -121,12 +121,12 @@ namespace godot {
         if ((size_t)array.size() != results->size) return ERR_PARAMETER_RANGE_ERROR;
         for (uint16_t i = 0; i < results->size; i++) {
           results->data[i] = encode_variant(array[i], context->results[i]);
-          if (results->data[i].kind == WASM_ANYREF) return ERR_INVALID_DATA;
+          if (results->data[i].kind == GODOT_WASM_EXTERNREF) return ERR_INVALID_DATA;
         }
         return OK;
       } else if (results->size == 1) {
         results->data[0] = encode_variant(variant, context->results[0]);
-        return results->data[0].kind == WASM_ANYREF ? ERR_INVALID_DATA : OK;
+        return results->data[0].kind == GODOT_WASM_EXTERNREF ? ERR_INVALID_DATA : OK;
       } else return ERR_INVALID_DATA;
     }
 
@@ -335,7 +335,7 @@ namespace godot {
       const Array& import = dict_safe_get(functions, it.first, Array());
       FAIL_IF(import.size() != 2, "Invalid import function " + it.first, ERR_CANT_CREATE);
       FAIL_IF(import[0].get_type() != Variant::OBJECT, "Invalid import target " + it.first, ERR_CANT_CREATE);
-      FAIL_IF(!INSTANCE_VALIDATE(import[0]), "Invalid import target " + it.first, ERR_CANT_CREATE);
+      FAIL_IF(!INSTANCE_FROM_ID(import[0]), "Invalid import target " + it.first, ERR_CANT_CREATE);
       FAIL_IF(import[1].get_type() != Variant::STRING, "Invalid import method " + it.first, ERR_CANT_CREATE);
       godot_wasm::ContextFuncImport* context = (godot_wasm::ContextFuncImport*)&it.second;
       context->target = import[0].operator Object*()->get_instance_id();
@@ -449,7 +449,7 @@ namespace godot {
     for (uint16_t i = 0; i < args.size(); i++) {
       Variant variant = args[i];
       wasm_val_t value = encode_variant(variant, context.params[i]);
-      FAIL_IF(value.kind == WASM_ANYREF, "Invalid argument type", NULL_VARIANT);
+      FAIL_IF(value.kind == GODOT_WASM_EXTERNREF, "Invalid argument type", NULL_VARIANT);
       args_vec.push_back(value);
     }
     wasm_val_vec_t f_args = { args_vec.size(), args_vec.data() };