diff --git a/broker/neb/src/initial.cc b/broker/neb/src/initial.cc
index 887141cd7a3..06cb56c2213 100644
--- a/broker/neb/src/initial.cc
+++ b/broker/neb/src/initial.cc
@@ -76,7 +76,7 @@ static void send_custom_variables_list(
         nscvd.type = NEBTYPE_HOSTCUSTOMVARIABLE_ADD;
         nscvd.timestamp.tv_sec = time(nullptr);
         nscvd.var_name = const_cast<char*>(name.c_str());
-        nscvd.var_value = const_cast<char*>(cit->second.get_value().c_str());
+        nscvd.var_value = const_cast<char*>(cit->second.value().c_str());
         nscvd.object_ptr = it->second.get();
 
         // Callback.
@@ -103,7 +103,7 @@ static void send_custom_variables_list(
         nscvd.type = NEBTYPE_SERVICECUSTOMVARIABLE_ADD;
         nscvd.timestamp.tv_sec = time(nullptr);
         nscvd.var_name = const_cast<char*>(name.c_str());
-        nscvd.var_value = const_cast<char*>(cit->second.get_value().c_str());
+        nscvd.var_value = const_cast<char*>(cit->second.value().c_str());
         nscvd.object_ptr = it->second.get();
 
         // Callback.
diff --git a/engine/inc/com/centreon/engine/configuration/anomalydetection.hh b/engine/inc/com/centreon/engine/configuration/anomalydetection.hh
index f36255c6cdc..87df2042b8c 100644
--- a/engine/inc/com/centreon/engine/configuration/anomalydetection.hh
+++ b/engine/inc/com/centreon/engine/configuration/anomalydetection.hh
@@ -1,5 +1,5 @@
 /*
-** Copyright 2011-2013,2015-2017, 2022 Centreon
+** Copyright 2011-2013,2015-2017, 2022-2023 Centreon
 **
 ** This file is part of Centreon Engine.
 **
@@ -21,9 +21,9 @@
 #define CCE_CONFIGURATION_ANOMALYDETECTION_HH
 
 #include "com/centreon/engine/common.hh"
+#include "com/centreon/engine/configuration/customvariable.hh"
 #include "com/centreon/engine/configuration/group.hh"
 #include "com/centreon/engine/configuration/object.hh"
-#include "com/centreon/engine/customvariable.hh"
 #include "com/centreon/engine/opt.hh"
 
 namespace com::centreon::engine {
@@ -69,8 +69,9 @@ class anomalydetection : public object {
   set_string& contacts() noexcept;
   set_string const& contacts() const noexcept;
   bool contacts_defined() const noexcept;
-  map_customvar const& customvariables() const noexcept;
-  map_customvar& customvariables() noexcept;
+  const std::unordered_map<std::string, customvariable>& customvariables()
+      const noexcept;
+  std::unordered_map<std::string, customvariable>& customvariables() noexcept;
   std::string const& display_name() const noexcept;
   std::string const& event_handler() const noexcept;
   bool event_handler_enabled() const noexcept;
@@ -190,7 +191,7 @@ class anomalydetection : public object {
   opt<unsigned int> _check_interval;
   group<set_string> _contactgroups;
   group<set_string> _contacts;
-  map_customvar _customvariables;
+  std::unordered_map<std::string, customvariable> _customvariables;
   std::string _display_name;
   std::string _event_handler;
   opt<bool> _event_handler_enabled;
diff --git a/engine/inc/com/centreon/engine/configuration/contact.hh b/engine/inc/com/centreon/engine/configuration/contact.hh
index de028c053a1..56b1df50155 100644
--- a/engine/inc/com/centreon/engine/configuration/contact.hh
+++ b/engine/inc/com/centreon/engine/configuration/contact.hh
@@ -22,9 +22,9 @@
 
 #include <absl/container/flat_hash_map.h>
 
+#include "com/centreon/engine/configuration/customvariable.hh"
 #include "com/centreon/engine/configuration/group.hh"
 #include "com/centreon/engine/configuration/object.hh"
-#include "com/centreon/engine/customvariable.hh"
 #include "com/centreon/engine/opt.hh"
 
 typedef std::vector<std::string> tab_string;
diff --git a/engine/inc/com/centreon/engine/configuration/customvariable.hh b/engine/inc/com/centreon/engine/configuration/customvariable.hh
new file mode 100644
index 00000000000..337c1830bf3
--- /dev/null
+++ b/engine/inc/com/centreon/engine/configuration/customvariable.hh
@@ -0,0 +1,48 @@
+/*
+ * Copyright 2023 Centreon (https://www.centreon.com/)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * For more information : contact@centreon.com
+ *
+ */
+#ifndef CCE_CONFIGURATION_CUSTOMVARIABLE_HH
+#define CCE_CONFIGURATION_CUSTOMVARIABLE_HH
+#include <string>
+
+namespace com::centreon::engine::configuration {
+/**
+ * @class customvariable customvariable.hh
+ * "com/centreon/engine/configuration/customvariable.hh"
+ * @brief This class represents a customvariable configuration.
+ *
+ * It is lighter than the engine::customvariable class and also it is
+ * separated from the engine core because the configuration module must be
+ * loadable from cbd.
+ */
+class customvariable {
+  std::string _value;
+  bool _is_sent;
+
+ public:
+  customvariable(std::string const& value = "", bool is_sent = false);
+  bool operator==(const customvariable& other) const;
+  ~customvariable() noexcept = default;
+  void set_sent(bool sent);
+  bool is_sent() const;
+  void set_value(const std::string& value);
+  const std::string& value() const;
+};
+}  // namespace com::centreon::engine::configuration
+
+#endif /* !CCE_CONFIGURATION_CUSTOMVARIABLE_HH */
diff --git a/engine/inc/com/centreon/engine/configuration/host.hh b/engine/inc/com/centreon/engine/configuration/host.hh
index 1db64c940a8..6bb32c67dcb 100644
--- a/engine/inc/com/centreon/engine/configuration/host.hh
+++ b/engine/inc/com/centreon/engine/configuration/host.hh
@@ -21,11 +21,11 @@
 #define CCE_CONFIGURATION_HOST_HH
 
 #include "com/centreon/engine/common.hh"
+#include "com/centreon/engine/configuration/customvariable.hh"
 #include "com/centreon/engine/configuration/group.hh"
 #include "com/centreon/engine/configuration/object.hh"
 #include "com/centreon/engine/configuration/point_2d.hh"
 #include "com/centreon/engine/configuration/point_3d.hh"
-#include "com/centreon/engine/customvariable.hh"
 #include "com/centreon/engine/opt.hh"
 
 namespace com::centreon::engine {
@@ -70,7 +70,8 @@ class host : public object {
   point_3d const& coords_3d() const noexcept;
   const std::unordered_map<std::string, customvariable>& customvariables()
       const noexcept;
-  std::unordered_map<std::string, customvariable>& customvariables() noexcept;
+  std::unordered_map<std::string, customvariable>&
+  mut_customvariables() noexcept;
   std::string const& display_name() const noexcept;
   std::string const& event_handler() const noexcept;
   bool event_handler_enabled() const noexcept;
diff --git a/engine/inc/com/centreon/engine/configuration/service.hh b/engine/inc/com/centreon/engine/configuration/service.hh
index 49fc7bd5853..5831b2efa12 100644
--- a/engine/inc/com/centreon/engine/configuration/service.hh
+++ b/engine/inc/com/centreon/engine/configuration/service.hh
@@ -1,34 +1,32 @@
-/*
-** Copyright 2011-2013,2015-2017-2022 Centreon
-**
-** This file is part of Centreon Engine.
-**
-** Centreon Engine is free software: you can redistribute it and/or
-** modify it under the terms of the GNU General Public License version 2
-** as published by the Free Software Foundation.
-**
-** Centreon Engine is distributed in the hope that it will be useful,
-** but WITHOUT ANY WARRANTY; without even the implied warranty of
-** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-** General Public License for more details.
-**
-** You should have received a copy of the GNU General Public License
-** along with Centreon Engine. If not, see
-** <http://www.gnu.org/licenses/>.
-*/
+/**
+ * Copyright 2011-2013,2015-2017-2022 Centreon
+ *
+ * This file is part of Centreon Engine.
+ *
+ * Centreon Engine is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * Centreon Engine is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Centreon Engine. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
 
 #ifndef CCE_CONFIGURATION_SERVICE_HH
 #define CCE_CONFIGURATION_SERVICE_HH
 
 #include "com/centreon/engine/common.hh"
+#include "com/centreon/engine/configuration/customvariable.hh"
 #include "com/centreon/engine/configuration/group.hh"
 #include "com/centreon/engine/configuration/object.hh"
-#include "com/centreon/engine/customvariable.hh"
 #include "com/centreon/engine/opt.hh"
 
-namespace com::centreon::engine {
-
-namespace configuration {
+namespace com::centreon::engine::configuration {
 
 class service : public object {
  public:
@@ -68,8 +66,10 @@ class service : public object {
   set_string& contacts() noexcept;
   set_string const& contacts() const noexcept;
   bool contacts_defined() const noexcept;
-  map_customvar const& customvariables() const noexcept;
-  map_customvar& customvariables() noexcept;
+  const std::unordered_map<std::string, customvariable>& customvariables()
+      const noexcept;
+  std::unordered_map<std::string, customvariable>&
+  mut_customvariables() noexcept;
   std::string const& display_name() const noexcept;
   std::string const& event_handler() const noexcept;
   bool event_handler_enabled() const noexcept;
@@ -185,7 +185,7 @@ class service : public object {
   std::string _check_period;
   group<set_string> _contactgroups;
   group<set_string> _contacts;
-  map_customvar _customvariables;
+  std::unordered_map<std::string, customvariable> _customvariables;
   std::string _display_name;
   std::string _event_handler;
   opt<bool> _event_handler_enabled;
@@ -231,8 +231,7 @@ typedef std::list<service_ptr> list_service;
 typedef std::set<service> set_service;
 typedef std::unordered_map<std::pair<std::string, std::string>, service_ptr>
     map_service;
-}  // namespace configuration
 
-}  // namespace com::centreon::engine
+}  // namespace com::centreon::engine::configuration
 
 #endif  // !CCE_CONFIGURATION_SERVICE_HH
diff --git a/engine/inc/com/centreon/engine/customvariable.hh b/engine/inc/com/centreon/engine/customvariable.hh
index cf1ad73e40a..3b2e7fefc2e 100644
--- a/engine/inc/com/centreon/engine/customvariable.hh
+++ b/engine/inc/com/centreon/engine/customvariable.hh
@@ -43,7 +43,7 @@ class customvariable {
   void set_sent(bool sent);
   bool is_sent() const;
   void set_value(std::string const& value);
-  std::string const& get_value() const;
+  const std::string& value() const;
   bool has_been_modified() const;
   void update(std::string const& value);
 
@@ -55,6 +55,6 @@ class customvariable {
 
 typedef std::unordered_map<std::string, customvariable> map_customvar;
 
-}
+}  // namespace com::centreon::engine
 
 #endif  // !CCE_OBJECTS_CUSTOMVARIABLE_HH
diff --git a/engine/src/anomalydetection.cc b/engine/src/anomalydetection.cc
index 08dcaadcd50..8fa79965660 100644
--- a/engine/src/anomalydetection.cc
+++ b/engine/src/anomalydetection.cc
@@ -1095,8 +1095,6 @@ bool anomalydetection::parse_perfdata(std::string const& perfdata,
   /* We should master this string, so no need to check if it is utf-8 */
   calculated_result.set_output(oss.str());
 
-  timestamp now(timestamp::now());
-
   // Update check result.
   timeval tv;
   gettimeofday(&tv, nullptr);
diff --git a/engine/src/commands/raw.cc b/engine/src/commands/raw.cc
index 50e195545a1..21774f804d9 100644
--- a/engine/src/commands/raw.cc
+++ b/engine/src/commands/raw.cc
@@ -394,9 +394,8 @@ void raw::_build_custom_contact_macro_environment(nagios_macros& macros,
   // Set custom contact variable into the environement
   for (auto const& cv : macros.custom_contact_vars) {
     if (!cv.first.empty()) {
-      std::string value(
-          clean_macro_chars(cv.second.get_value(),
-                            STRIP_ILLEGAL_MACRO_CHARS | ESCAPE_MACRO_CHARS));
+      std::string value(clean_macro_chars(
+          cv.second.value(), STRIP_ILLEGAL_MACRO_CHARS | ESCAPE_MACRO_CHARS));
       std::string line;
       line.append(MACRO_ENV_VAR_PREFIX);
       line.append(cv.first);
@@ -429,9 +428,8 @@ void raw::_build_custom_host_macro_environment(nagios_macros& macros,
   // Set custom host variable into the environement
   for (auto const& cv : macros.custom_host_vars) {
     if (!cv.first.empty()) {
-      std::string value(
-          clean_macro_chars(cv.second.get_value(),
-                            STRIP_ILLEGAL_MACRO_CHARS | ESCAPE_MACRO_CHARS));
+      std::string value(clean_macro_chars(
+          cv.second.value(), STRIP_ILLEGAL_MACRO_CHARS | ESCAPE_MACRO_CHARS));
       std::string line;
       line.append(MACRO_ENV_VAR_PREFIX);
       line.append(cv.first);
@@ -464,9 +462,8 @@ void raw::_build_custom_service_macro_environment(nagios_macros& macros,
   // Set custom service variable into the environement
   for (auto const& cv : macros.custom_service_vars) {
     if (!cv.first.empty()) {
-      std::string value(
-          clean_macro_chars(cv.second.get_value(),
-                            STRIP_ILLEGAL_MACRO_CHARS | ESCAPE_MACRO_CHARS));
+      std::string value(clean_macro_chars(
+          cv.second.value(), STRIP_ILLEGAL_MACRO_CHARS | ESCAPE_MACRO_CHARS));
       std::string line;
       line.append(MACRO_ENV_VAR_PREFIX);
       line.append(cv.first);
diff --git a/engine/src/configuration/CMakeLists.txt b/engine/src/configuration/CMakeLists.txt
index b0bd8910f26..ff0c4fcd7a0 100644
--- a/engine/src/configuration/CMakeLists.txt
+++ b/engine/src/configuration/CMakeLists.txt
@@ -32,6 +32,7 @@ set(FILES
     "${SRC_DIR}/connector.cc"
     "${SRC_DIR}/contact.cc"
     "${SRC_DIR}/contactgroup.cc"
+    "${SRC_DIR}/customvariable.cc"
     "${SRC_DIR}/extended_conf.cc"
     "${SRC_DIR}/group.cc"
     "${SRC_DIR}/host.cc"
diff --git a/engine/src/configuration/anomalydetection.cc b/engine/src/configuration/anomalydetection.cc
index f6598b379e2..cd59aadc1ba 100644
--- a/engine/src/configuration/anomalydetection.cc
+++ b/engine/src/configuration/anomalydetection.cc
@@ -1012,8 +1012,8 @@ bool anomalydetection::contacts_defined() const noexcept {
  *
  *  @return The customvariables.
  */
-com::centreon::engine::map_customvar const& anomalydetection::customvariables()
-    const noexcept {
+const std::unordered_map<std::string, customvariable>&
+anomalydetection::customvariables() const noexcept {
   return _customvariables;
 }
 
@@ -1022,7 +1022,7 @@ com::centreon::engine::map_customvar const& anomalydetection::customvariables()
  *
  *  @return The customvariables.
  */
-com::centreon::engine::map_customvar&
+std::unordered_map<std::string, customvariable>&
 anomalydetection::customvariables() noexcept {
   return _customvariables;
 }
diff --git a/engine/src/configuration/applier/anomalydetection.cc b/engine/src/configuration/applier/anomalydetection.cc
index 42153fbb4f9..fd5be1e8ca0 100644
--- a/engine/src/configuration/applier/anomalydetection.cc
+++ b/engine/src/configuration/applier/anomalydetection.cc
@@ -147,12 +147,13 @@ void applier::anomalydetection::add_object(
   for (auto it = obj.customvariables().begin(),
             end = obj.customvariables().end();
        it != end; ++it) {
-    ad->custom_variables[it->first] = it->second;
+    ad->custom_variables[it->first] =
+        engine::customvariable(it->second.value(), it->second.is_sent());
 
     if (it->second.is_sent()) {
       timeval tv(get_broker_timestamp(nullptr));
       broker_custom_variable(NEBTYPE_SERVICECUSTOMVARIABLE_ADD, ad,
-                             it->first.c_str(), it->second.get_value().c_str(),
+                             it->first.c_str(), it->second.value().c_str(),
                              &tv);
     }
   }
@@ -368,20 +369,19 @@ void applier::anomalydetection::modify_object(
       if (c.second.is_sent()) {
         timeval tv(get_broker_timestamp(nullptr));
         broker_custom_variable(NEBTYPE_SERVICECUSTOMVARIABLE_DELETE, s.get(),
-                               c.first.c_str(), c.second.get_value().c_str(),
-                               &tv);
+                               c.first.c_str(), c.second.value().c_str(), &tv);
       }
     }
     s->custom_variables.clear();
 
     for (auto& c : obj.customvariables()) {
-      s->custom_variables[c.first] = c.second;
+      s->custom_variables[c.first] =
+          engine::customvariable(c.second.value(), c.second.is_sent());
 
       if (c.second.is_sent()) {
         timeval tv(get_broker_timestamp(nullptr));
         broker_custom_variable(NEBTYPE_SERVICECUSTOMVARIABLE_ADD, s.get(),
-                               c.first.c_str(), c.second.get_value().c_str(),
-                               &tv);
+                               c.first.c_str(), c.second.value().c_str(), &tv);
       }
     }
   }
diff --git a/engine/src/configuration/applier/contact.cc b/engine/src/configuration/applier/contact.cc
index 48b716dcaae..8a4289c5036 100644
--- a/engine/src/configuration/applier/contact.cc
+++ b/engine/src/configuration/applier/contact.cc
@@ -105,12 +105,14 @@ void applier::contact::add_object(configuration::contact const& obj) {
   for (auto it = obj.customvariables().begin(),
             end = obj.customvariables().end();
        it != end; ++it) {
-    c->get_custom_variables()[it->first] = it->second;
+    auto& cv = c->get_custom_variables()[it->first];
+    cv.set_value(it->second.value());
+    cv.set_sent(it->second.is_sent());
 
     if (it->second.is_sent()) {
       timeval tv(get_broker_timestamp(nullptr));
       broker_custom_variable(NEBTYPE_CONTACTCUSTOMVARIABLE_ADD, c.get(),
-                             it->first.c_str(), it->second.get_value().c_str(),
+                             it->first.c_str(), it->second.value().c_str(),
                              &tv);
     }
   }
@@ -250,20 +252,22 @@ void applier::contact::modify_object(configuration::contact const& obj) {
       if (cus.second.is_sent()) {
         timeval tv(get_broker_timestamp(nullptr));
         broker_custom_variable(NEBTYPE_CONTACTCUSTOMVARIABLE_DELETE, c,
-                               cus.first.c_str(),
-                               cus.second.get_value().c_str(), &tv);
+                               cus.first.c_str(), cus.second.value().c_str(),
+                               &tv);
       }
     }
     c->get_custom_variables().clear();
 
     for (auto& cus : obj.customvariables()) {
-      c->get_custom_variables()[cus.first] = cus.second;
+      auto& cv = c->get_custom_variables()[cus.first];
+      cv.set_value(cus.second.value());
+      cv.set_sent(cus.second.is_sent());
 
       if (cus.second.is_sent()) {
         timeval tv(get_broker_timestamp(nullptr));
         broker_custom_variable(NEBTYPE_CONTACTCUSTOMVARIABLE_ADD, c,
-                               cus.first.c_str(),
-                               cus.second.get_value().c_str(), &tv);
+                               cus.first.c_str(), cus.second.value().c_str(),
+                               &tv);
       }
     }
   }
diff --git a/engine/src/configuration/applier/host.cc b/engine/src/configuration/applier/host.cc
index 4a8ff8c752e..6577915df86 100644
--- a/engine/src/configuration/applier/host.cc
+++ b/engine/src/configuration/applier/host.cc
@@ -120,15 +120,16 @@ void applier::host::add_object(configuration::host const& obj) {
     h->get_contactgroups().insert({*it, nullptr});
 
   // Custom variables.
-  for (map_customvar::const_iterator it(obj.customvariables().begin()),
-       end(obj.customvariables().end());
+  for (auto it = obj.customvariables().begin(),
+            end = obj.customvariables().end();
        it != end; ++it) {
-    h->custom_variables[it->first] = it->second;
+    h->custom_variables[it->first] =
+        engine::customvariable(it->second.value(), it->second.is_sent());
 
     if (it->second.is_sent()) {
       timeval tv(get_broker_timestamp(nullptr));
       broker_custom_variable(NEBTYPE_HOSTCUSTOMVARIABLE_ADD, h.get(),
-                             it->first.c_str(), it->second.get_value().c_str(),
+                             it->first.c_str(), it->second.value().c_str(),
                              &tv);
     }
   }
@@ -170,53 +171,6 @@ void applier::host::add_object(configuration::host const& obj) {
                             h.get(), MODATTR_ALL);
 }
 
-/**
- *  @brief Expand a host.
- *
- *  During expansion, the host will be added to its host groups. These
- *  will be modified in the state.
- *
- *  @param[int,out] s   Configuration state.
- */
-void applier::host::expand_objects(configuration::state& s) {
-  // Browse all hosts.
-  for (auto& host_cfg : s.hosts()) {
-    // Should custom variables be sent to broker ?
-    for (map_customvar::iterator
-             it(const_cast<map_customvar&>(host_cfg.customvariables()).begin()),
-         end(const_cast<map_customvar&>(host_cfg.customvariables()).end());
-         it != end; ++it) {
-      if (!s.enable_macros_filter() ||
-          s.macros_filter().find(it->first) != s.macros_filter().end()) {
-        it->second.set_sent(true);
-      }
-    }
-
-    // Browse current host's groups.
-    for (set_string::const_iterator it_group(host_cfg.hostgroups().begin()),
-         end_group(host_cfg.hostgroups().end());
-         it_group != end_group; ++it_group) {
-      // Find host group.
-      configuration::set_hostgroup::iterator group(
-          s.hostgroups_find(*it_group));
-      if (group == s.hostgroups().end())
-        throw(engine_error()
-              << "Could not add host '" << host_cfg.host_name()
-              << "' to non-existing host group '" << *it_group << "'");
-
-      // Remove host group from state.
-      configuration::hostgroup backup(*group);
-      s.hostgroups().erase(group);
-
-      // Add host to group members.
-      backup.members().insert(host_cfg.host_name());
-
-      // Reinsert host group.
-      s.hostgroups().insert(backup);
-    }
-  }
-}
-
 /**
  *  Modified host.
  *
@@ -382,19 +336,20 @@ void applier::host::modify_object(configuration::host const& obj) {
         timeval tv(get_broker_timestamp(nullptr));
         broker_custom_variable(NEBTYPE_HOSTCUSTOMVARIABLE_DELETE,
                                it_obj->second.get(), c.first.c_str(),
-                               c.second.get_value().c_str(), &tv);
+                               c.second.value().c_str(), &tv);
       }
     }
     it_obj->second->custom_variables.clear();
 
     for (auto& c : obj.customvariables()) {
-      it_obj->second->custom_variables[c.first] = c.second;
+      it_obj->second->custom_variables[c.first] =
+          engine::customvariable(c.second.value(), c.second.is_sent());
 
       if (c.second.is_sent()) {
         timeval tv(get_broker_timestamp(nullptr));
         broker_custom_variable(NEBTYPE_HOSTCUSTOMVARIABLE_ADD,
                                it_obj->second.get(), c.first.c_str(),
-                               c.second.get_value().c_str(), &tv);
+                               c.second.value().c_str(), &tv);
       }
     }
   }
@@ -541,3 +496,52 @@ void applier::host::resolve_object(configuration::host const& obj) {
   // Resolve host.
   it->second->resolve(config_warnings, config_errors);
 }
+
+/**
+ *  @brief Expand a host.
+ *
+ *  During expansion, the host will be added to its host groups. These
+ *  will be modified in the state.
+ *
+ *  @param[int,out] s   Configuration state.
+ */
+void applier::host::expand_objects(configuration::state& s) {
+  // Browse all hosts.
+  set_host new_hosts;
+  for (auto host_cfg : s.hosts()) {
+    // Should custom variables be sent to broker ?
+    for (auto it = host_cfg.mut_customvariables().begin(),
+              end = host_cfg.mut_customvariables().end();
+         it != end; ++it) {
+      if (!s.enable_macros_filter() ||
+          s.macros_filter().find(it->first) != s.macros_filter().end()) {
+        it->second.set_sent(true);
+      }
+    }
+
+    // Browse current host's groups.
+    for (set_string::const_iterator it_group(host_cfg.hostgroups().begin()),
+         end_group(host_cfg.hostgroups().end());
+         it_group != end_group; ++it_group) {
+      // Find host group.
+      configuration::set_hostgroup::iterator group(
+          s.hostgroups_find(*it_group));
+      if (group == s.hostgroups().end())
+        throw(engine_error()
+              << "Could not add host '" << host_cfg.host_name()
+              << "' to non-existing host group '" << *it_group << "'");
+
+      // Remove host group from state.
+      configuration::hostgroup backup(*group);
+      s.hostgroups().erase(group);
+
+      // Add host to group members.
+      backup.members().insert(host_cfg.host_name());
+
+      // Reinsert host group.
+      s.hostgroups().insert(backup);
+    }
+    new_hosts.insert(host_cfg);
+  }
+  s.hosts() = std::move(new_hosts);
+}
diff --git a/engine/src/configuration/applier/service.cc b/engine/src/configuration/applier/service.cc
index 3914fcb85ac..f7e7ff1fca6 100644
--- a/engine/src/configuration/applier/service.cc
+++ b/engine/src/configuration/applier/service.cc
@@ -186,15 +186,16 @@ void applier::service::add_object(configuration::service const& obj) {
     svc->get_contactgroups().insert({*it, nullptr});
 
   // Add custom variables.
-  for (map_customvar::const_iterator it(obj.customvariables().begin()),
-       end(obj.customvariables().end());
+  for (auto it = obj.customvariables().begin(),
+            end = obj.customvariables().end();
        it != end; ++it) {
-    svc->custom_variables[it->first] = it->second;
+    svc->custom_variables[it->first] =
+        engine::customvariable(it->second.value(), it->second.is_sent());
 
     if (it->second.is_sent()) {
       timeval tv(get_broker_timestamp(nullptr));
       broker_custom_variable(NEBTYPE_SERVICECUSTOMVARIABLE_ADD, svc,
-                             it->first.c_str(), it->second.get_value().c_str(),
+                             it->first.c_str(), it->second.value().c_str(),
                              &tv);
     }
   }
@@ -239,13 +240,10 @@ void applier::service::add_object(configuration::service const& obj) {
 void applier::service::expand_objects(configuration::state& s) {
   // Browse all services.
   configuration::set_service expanded;
-  for (configuration::set_service::iterator it_svc(s.services().begin()),
-       end_svc(s.services().end());
-       it_svc != end_svc; ++it_svc) {
+  for (auto svc_cfg : s.services()) {
     // Should custom variables be sent to broker ?
-    for (map_customvar::iterator
-             it(const_cast<map_customvar&>(it_svc->customvariables()).begin()),
-         end(const_cast<map_customvar&>(it_svc->customvariables()).end());
+    for (auto it = svc_cfg.mut_customvariables().begin(),
+              end = svc_cfg.mut_customvariables().end();
          it != end; ++it) {
       if (!s.enable_macros_filter() ||
           s.macros_filter().find(it->first) != s.macros_filter().end()) {
@@ -257,24 +255,24 @@ void applier::service::expand_objects(configuration::state& s) {
     std::set<std::string> target_hosts;
 
     // Hosts members.
-    target_hosts = it_svc->hosts();
+    target_hosts = svc_cfg.hosts();
 
     // Host group members.
-    for (set_string::const_iterator it(it_svc->hostgroups().begin()),
-         end(it_svc->hostgroups().end());
+    for (set_string::const_iterator it(svc_cfg.hostgroups().begin()),
+         end(svc_cfg.hostgroups().end());
          it != end; ++it) {
       // Find host group.
       set_hostgroup::iterator it2(s.hostgroups_find(*it));
       if (it2 == s.hostgroups().end())
         throw(engine_error() << "Could not find host group '" << *it
                              << "' on which to apply service '"
-                             << it_svc->service_description() << "'");
+                             << svc_cfg.service_description() << "'");
 
       // Check host group and user configuration.
       if (it2->members().empty() && !s.allow_empty_hostgroup_assignment())
         throw(engine_error() << "Could not expand host group '" << *it
                              << "' specified in service '"
-                             << it_svc->service_description() << "'");
+                             << svc_cfg.service_description() << "'");
 
       // Add host group members.
       target_hosts.insert(it2->members().begin(), it2->members().end());
@@ -285,7 +283,7 @@ void applier::service::expand_objects(configuration::state& s) {
          end(target_hosts.end());
          it != end; ++it) {
       // Create service instance.
-      configuration::service svc(*it_svc);
+      configuration::service svc(svc_cfg);
       svc.hostgroups().clear();
       svc.hosts().clear();
       svc.hosts().insert(*it);
@@ -483,20 +481,19 @@ void applier::service::modify_object(configuration::service const& obj) {
       if (c.second.is_sent()) {
         timeval tv(get_broker_timestamp(nullptr));
         broker_custom_variable(NEBTYPE_SERVICECUSTOMVARIABLE_DELETE, s.get(),
-                               c.first.c_str(), c.second.get_value().c_str(),
-                               &tv);
+                               c.first.c_str(), c.second.value().c_str(), &tv);
       }
     }
     s->custom_variables.clear();
 
     for (auto& c : obj.customvariables()) {
-      s->custom_variables[c.first] = c.second;
+      s->custom_variables[c.first] =
+          engine::customvariable(c.second.value(), c.second.is_sent());
 
       if (c.second.is_sent()) {
         timeval tv(get_broker_timestamp(nullptr));
         broker_custom_variable(NEBTYPE_SERVICECUSTOMVARIABLE_ADD, s.get(),
-                               c.first.c_str(), c.second.get_value().c_str(),
-                               &tv);
+                               c.first.c_str(), c.second.value().c_str(), &tv);
       }
     }
   }
diff --git a/engine/src/configuration/customvariable.cc b/engine/src/configuration/customvariable.cc
new file mode 100644
index 00000000000..d41dd32df75
--- /dev/null
+++ b/engine/src/configuration/customvariable.cc
@@ -0,0 +1,56 @@
+/*
+ * Copyright 2023 Centreon (https://www.centreon.com/)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * For more information : contact@centreon.com
+ *
+ */
+
+#include "com/centreon/engine/configuration/customvariable.hh"
+
+using namespace com::centreon::engine::configuration;
+
+customvariable::customvariable(const std::string& value, bool is_sent)
+    : _value{value}, _is_sent{is_sent} {}
+
+// customvariable::customvariable(customvariable const& other)
+//     : _value{other._value}, _is_sent{other._is_sent} {}
+
+// customvariable& customvariable::operator=(const customvariable& other) {
+//   if (this != &other) {
+//     _value = other.value;
+//     _is_sent = other._is_sent;
+//   }
+//   return *this;
+// }
+
+void customvariable::set_sent(bool sent) {
+  _is_sent = sent;
+}
+
+bool customvariable::is_sent() const {
+  return _is_sent;
+}
+
+void customvariable::set_value(const std::string& value) {
+  _value = value;
+}
+
+const std::string& customvariable::value() const {
+  return _value;
+}
+
+bool customvariable::operator==(const customvariable& other) const {
+  return _value == other._value && _is_sent == other._is_sent;
+}
diff --git a/engine/src/configuration/host.cc b/engine/src/configuration/host.cc
index 2cd983842a6..ed7864a5547 100644
--- a/engine/src/configuration/host.cc
+++ b/engine/src/configuration/host.cc
@@ -658,8 +658,8 @@ point_3d const& host::coords_3d() const noexcept {
  *
  *  @return The customvariables.
  */
-const std::unordered_map<std::string, com::centreon::engine::customvariable>&
-host::customvariables() const noexcept {
+const std::unordered_map<std::string, customvariable>& host::customvariables()
+    const noexcept {
   return _customvariables;
 }
 
@@ -668,8 +668,8 @@ host::customvariables() const noexcept {
  *
  *  @return The customvariables.
  */
-std::unordered_map<std::string, com::centreon::engine::customvariable>&
-host::customvariables() noexcept {
+std::unordered_map<std::string, customvariable>&
+host::mut_customvariables() noexcept {
   return _customvariables;
 }
 
diff --git a/engine/src/configuration/service.cc b/engine/src/configuration/service.cc
index e9d8ebabe6c..769d7025e00 100644
--- a/engine/src/configuration/service.cc
+++ b/engine/src/configuration/service.cc
@@ -937,7 +937,7 @@ bool service::contacts_defined() const noexcept {
  *
  *  @return The customvariables.
  */
-const std::unordered_map<std::string, com::centreon::engine::customvariable>&
+const std::unordered_map<std::string, customvariable>&
 service::customvariables() const noexcept {
   return _customvariables;
 }
@@ -947,8 +947,8 @@ service::customvariables() const noexcept {
  *
  *  @return The customvariables.
  */
-std::unordered_map<std::string, com::centreon::engine::customvariable>&
-service::customvariables() noexcept {
+std::unordered_map<std::string, customvariable>&
+service::mut_customvariables() noexcept {
   return _customvariables;
 }
 
diff --git a/engine/src/customvariable.cc b/engine/src/customvariable.cc
index 99be377b54f..077a437048d 100644
--- a/engine/src/customvariable.cc
+++ b/engine/src/customvariable.cc
@@ -83,7 +83,7 @@ bool customvariable::is_sent() const {
  *
  * @return The value of the customvariable
  */
-std::string const& customvariable::get_value() const {
+const std::string& customvariable::value() const {
   return _value;
 }
 
diff --git a/engine/src/macros.cc b/engine/src/macros.cc
index 451c3756464..673b76b8856 100644
--- a/engine/src/macros.cc
+++ b/engine/src/macros.cc
@@ -644,7 +644,7 @@ int grab_custom_object_macro_r(nagios_macros* mac,
   /* get the custom variable */
   for (auto const& cv : vars) {
     if (macro_name == cv.first) {
-      output = cv.second.get_value();
+      output = cv.second.value();
       result = OK;
       break;
     }
diff --git a/engine/src/retention/applier/contact.cc b/engine/src/retention/applier/contact.cc
index 69f9c1fbca3..5ffce899e14 100644
--- a/engine/src/retention/applier/contact.cc
+++ b/engine/src/retention/applier/contact.cc
@@ -1,21 +1,21 @@
 /**
-* Copyright 2011-2013,2016 Merethis
-*
-* This file is part of Centreon Engine.
-*
-* Centreon Engine is free software: you can redistribute it and/or
-* modify it under the terms of the GNU General Public License version 2
-* as published by the Free Software Foundation.
-*
-* Centreon Engine is distributed in the hope that it will be useful,
-* but WITHOUT ANY WARRANTY; without even the implied warranty of
-* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-* General Public License for more details.
-*
-* You should have received a copy of the GNU General Public License
-* along with Centreon Engine. If not, see
-* <http://www.gnu.org/licenses/>.
-*/
+ * Copyright 2011-2013,2016 Merethis
+ *
+ * This file is part of Centreon Engine.
+ *
+ * Centreon Engine is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * Centreon Engine is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Centreon Engine. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
 
 #include "com/centreon/engine/retention/applier/contact.hh"
 #include "com/centreon/engine/configuration/applier/state.hh"
@@ -129,7 +129,7 @@ void applier::contact::_update(configuration::state const& config,
     if (!state.customvariables().empty() &&
         (obj->get_modified_attributes() & MODATTR_CUSTOM_VARIABLE)) {
       for (auto const& cv : state.customvariables()) {
-        obj->get_custom_variables()[cv.first].update(cv.second.get_value());
+        obj->get_custom_variables()[cv.first].update(cv.second.value());
       }
     }
   }
diff --git a/engine/src/retention/applier/host.cc b/engine/src/retention/applier/host.cc
index c4c3057d216..c1f6e94f6a9 100644
--- a/engine/src/retention/applier/host.cc
+++ b/engine/src/retention/applier/host.cc
@@ -1,21 +1,21 @@
 /**
-* Copyright 2011-2013,2015-2016,2022 Centreon
-*
-* This file is part of Centreon Engine.
-*
-* Centreon Engine is free software: you can redistribute it and/or
-* modify it under the terms of the GNU General Public License version 2
-* as published by the Free Software Foundation.
-*
-* Centreon Engine is distributed in the hope that it will be useful,
-* but WITHOUT ANY WARRANTY; without even the implied warranty of
-* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-* General Public License for more details.
-*
-* You should have received a copy of the GNU General Public License
-* along with Centreon Engine. If not, see
-* <http://www.gnu.org/licenses/>.
-*/
+ * Copyright 2011-2013,2015-2016,2022 Centreon
+ *
+ * This file is part of Centreon Engine.
+ *
+ * Centreon Engine is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * Centreon Engine is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Centreon Engine. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
 
 #include "com/centreon/engine/retention/applier/host.hh"
 #include "com/centreon/engine/configuration/applier/state.hh"
@@ -255,7 +255,7 @@ void applier::host::_update(configuration::state const& config,
       for (map_customvar::const_iterator it(state.customvariables().begin()),
            end(state.customvariables().end());
            it != end; ++it)
-        obj.custom_variables[it->first].update(it->second.get_value());
+        obj.custom_variables[it->first].update(it->second.value());
     }
   }
   // Adjust modified attributes if necessary.
diff --git a/engine/src/retention/applier/service.cc b/engine/src/retention/applier/service.cc
index d8e060eec3b..13783948e2d 100644
--- a/engine/src/retention/applier/service.cc
+++ b/engine/src/retention/applier/service.cc
@@ -264,7 +264,7 @@ void applier::service::update(configuration::state const& config,
       for (map_customvar::const_iterator it(state.customvariables().begin()),
            end(state.customvariables().end());
            it != end; ++it)
-        obj.custom_variables[it->first].update(it->second.get_value());
+        obj.custom_variables[it->first].update(it->second.value());
     }
   }
   // Adjust modified attributes if necessary.
diff --git a/engine/src/retention/dump.cc b/engine/src/retention/dump.cc
index f619c857937..cc129497c71 100644
--- a/engine/src/retention/dump.cc
+++ b/engine/src/retention/dump.cc
@@ -192,7 +192,7 @@ std::ostream& dump::customvariables(std::ostream& os,
                                     map_customvar const& obj) {
   for (auto const& cv : obj)
     os << "_" << cv.first << "=" << cv.second.has_been_modified() << ","
-       << cv.second.get_value() << "\n";
+       << cv.second.value() << "\n";
   return os;
 }
 
diff --git a/engine/src/xsddefault.cc b/engine/src/xsddefault.cc
index 9ae791a047d..93a219b608d 100644
--- a/engine/src/xsddefault.cc
+++ b/engine/src/xsddefault.cc
@@ -449,7 +449,7 @@ int xsddefault_save_status_data() {
     for (auto const& cv : it->second->custom_variables) {
       if (!cv.first.empty())
         stream << "\t_" << cv.first << "=" << cv.second.has_been_modified()
-               << ";" << cv.second.get_value() << "\n";
+               << ";" << cv.second.value() << "\n";
     }
     stream << "\t}\n\n";
   }
@@ -625,7 +625,7 @@ int xsddefault_save_status_data() {
     for (auto const& cv : it->second->custom_variables) {
       if (!cv.first.empty())
         stream << "\t_" << cv.first << "=" << cv.second.has_been_modified()
-               << ";" << cv.second.get_value() << "\n";
+               << ";" << cv.second.value() << "\n";
     }
     stream << "\t}\n\n";
   }
@@ -669,7 +669,7 @@ int xsddefault_save_status_data() {
     for (auto const& cv : cntct->get_custom_variables()) {
       if (!cv.first.empty())
         stream << "\t_" << cv.first << "=" << cv.second.has_been_modified()
-               << ";" << cv.second.get_value() << "\n";
+               << ";" << cv.second.value() << "\n";
     }
     stream << "\t}\n\n";
   }
diff --git a/engine/tests/configuration/applier/applier-contact.cc b/engine/tests/configuration/applier/applier-contact.cc
index d55dc5ab9ad..cf7752674be 100644
--- a/engine/tests/configuration/applier/applier-contact.cc
+++ b/engine/tests/configuration/applier/applier-contact.cc
@@ -133,8 +133,7 @@ TEST_F(ApplierContact, ModifyContactFromConfig) {
   ASSERT_TRUE(ctct.parse("service_notification_commands", "svc1,svc2"));
   ASSERT_TRUE(ctct.parse("_superVar", "superValue"));
   ASSERT_TRUE(ctct.customvariables().size() == 1);
-  ASSERT_TRUE(ctct.customvariables().at("superVar").get_value() ==
-              "superValue");
+  ASSERT_TRUE(ctct.customvariables().at("superVar").value() == "superValue");
 
   configuration::applier::command cmd_aply;
   configuration::applier::connector cnn_aply;
@@ -159,9 +158,9 @@ TEST_F(ApplierContact, ModifyContactFromConfig) {
   contact_map::const_iterator ct_it{engine::contact::contacts.find("test")};
   ASSERT_TRUE(ct_it != engine::contact::contacts.end());
   ASSERT_EQ(ct_it->second->get_custom_variables().size(), 2u);
-  ASSERT_TRUE(ct_it->second->get_custom_variables()["superVar"].get_value() ==
+  ASSERT_TRUE(ct_it->second->get_custom_variables()["superVar"].value() ==
               "Super");
-  ASSERT_TRUE(ct_it->second->get_custom_variables()["superVar1"].get_value() ==
+  ASSERT_TRUE(ct_it->second->get_custom_variables()["superVar1"].value() ==
               "Super1");
   ASSERT_TRUE(ct_it->second->get_alias() == "newAlias");
   ASSERT_FALSE(ct_it->second->notify_on(notifier::service_notification,
diff --git a/engine/tests/configuration/applier/applier-state.cc b/engine/tests/configuration/applier/applier-state.cc
index cd6feb66e0a..cf5251b391a 100644
--- a/engine/tests/configuration/applier/applier-state.cc
+++ b/engine/tests/configuration/applier/applier-state.cc
@@ -891,7 +891,7 @@ TEST_F(ApplierState, StateLegacyParsing) {
   ASSERT_EQ(adit->dependent_service_id(), 1);
   ASSERT_TRUE(adit->metric_name() == "metric2");
   ASSERT_EQ(adit->customvariables().size(), 1);
-  ASSERT_EQ(adit->customvariables().at("ad_cv").get_value(),
+  ASSERT_EQ(adit->customvariables().at("ad_cv").value(),
             std::string("this_is_a_test"));
   ASSERT_EQ(adit->contactgroups().size(), 2);
   ASSERT_EQ(adit->contacts().size(), 1);
diff --git a/engine/tests/enginerpc/enginerpc.cc b/engine/tests/enginerpc/enginerpc.cc
index 762e1886436..2cc77c5d18e 100644
--- a/engine/tests/enginerpc/enginerpc.cc
+++ b/engine/tests/enginerpc/enginerpc.cc
@@ -1688,7 +1688,7 @@ TEST_F(EngineRpc, ChangeHostObjectCustomVar) {
   th->join();
 
   ASSERT_EQ(_host->custom_variables.size(), 1u);
-  ASSERT_EQ(_host->custom_variables["TEST_VAR"].get_value(), "test_val");
+  ASSERT_EQ(_host->custom_variables["TEST_VAR"].value(), "test_val");
   _host->custom_variables.clear();
   ASSERT_EQ(_host->custom_variables.size(), 0u);
   erpc.shutdown();
@@ -1715,7 +1715,7 @@ TEST_F(EngineRpc, ChangeServiceObjectCustomVar) {
   th->join();
 
   ASSERT_EQ(_svc->custom_variables.size(), 1u);
-  ASSERT_EQ(_svc->custom_variables["TEST_VAR"].get_value(), "test_val");
+  ASSERT_EQ(_svc->custom_variables["TEST_VAR"].value(), "test_val");
   _svc->custom_variables.clear();
   ASSERT_EQ(_svc->custom_variables.size(), 0u);
   erpc.shutdown();
@@ -1740,8 +1740,7 @@ TEST_F(EngineRpc, ChangeContactObjectCustomVar) {
   condvar.notify_one();
   th->join();
   ASSERT_EQ(_contact->get_custom_variables().size(), 1u);
-  ASSERT_EQ(_contact->get_custom_variables()["TEST_VAR"].get_value(),
-            "test_val");
+  ASSERT_EQ(_contact->get_custom_variables()["TEST_VAR"].value(), "test_val");
 
   erpc.shutdown();
 }