diff --git a/include/mementar/API/mementar/ActionsPublisher.h b/include/mementar/API/mementar/ActionsPublisher.h
index 2241f8d..9e3f057 100644
--- a/include/mementar/API/mementar/ActionsPublisher.h
+++ b/include/mementar/API/mementar/ActionsPublisher.h
@@ -18,11 +18,20 @@ namespace mementar {
     void insertEnd(const std::string& name, time_t end_stamp = time(nullptr));
     void insertEnd(const std::string& name, compat::mem_ros::Time end_stamp = compat::mem_ros::Node::get().currentTime());
 
+    /// @brief Register a callback function to get notifications from the feeder.
+    /// @param callback is the callback function taking a string.
+    void registerFeederNotificationCallback(const std::function<void(const std::string&)>& callback) { feeder_notification_callback_ = callback; }
+
   private:
+    std::function<void(const std::string&)> feeder_notification_callback_;
+
     compat::mem_ros::Publisher<compat::MementarAction> pub_;
+    compat::mem_ros::Subscriber<std_msgs_compat::String> feeder_notif_sub_;
 
     void publish(const std::string& name, time_t start_stamp, time_t end_stamp);
     void publish(const std::string& name, compat::mem_ros::Time start_stamp, compat::mem_ros::Time end_stamp);
+
+    void feederNotificationCallback(const compat::mem_ros::MessageWrapper<std_msgs_compat::String>& msg);
   };
 
 } // namespace mementar
diff --git a/include/mementar/API/mementar/ActionsSubscriber.h b/include/mementar/API/mementar/ActionsSubscriber.h
index 93c7889..d464e51 100644
--- a/include/mementar/API/mementar/ActionsSubscriber.h
+++ b/include/mementar/API/mementar/ActionsSubscriber.h
@@ -15,10 +15,7 @@ namespace mementar {
   {
   public:
     ActionsSubscriber(const std::function<void(const std::string&)>& callback,
-                      const std::string& name = "",
-                      bool spin_thread = true);
-    ActionsSubscriber(const std::function<void(const std::string&)>& callback,
-                      bool spin_thread);
+                      const std::string& name = "");
 
     bool subscribeToStart(const std::string& name, size_t count = -1);
     bool subscribeToEnd(const std::string& name, size_t count = -1);
diff --git a/include/mementar/API/mementar/OccasionsPublisher.h b/include/mementar/API/mementar/OccasionsPublisher.h
index fc72c09..6c869b9 100644
--- a/include/mementar/API/mementar/OccasionsPublisher.h
+++ b/include/mementar/API/mementar/OccasionsPublisher.h
@@ -14,12 +14,23 @@ namespace mementar {
   public:
     OccasionsPublisher(const std::string& name = "");
 
-    void insert(const Fact& fact, time_t stamp = time(nullptr));
+    void insert(const Fact& fact, mementar::compat::mem_ros::Time stamp = compat::mem_ros::Node::get().currentTime());
+    void insert(const Fact& fact, time_t end_stamp);
+
+    /// @brief Register a callback function to get notifications from the feeder.
+    /// @param callback is the callback function taking a string.
+    void registerFeederNotificationCallback(const std::function<void(const std::string&)>& callback) { feeder_notification_callback_ = callback; }
 
   private:
+    std::function<void(const std::string&)> feeder_notification_callback_;
+
     compat::mem_ros::Publisher<compat::StampedString> pub_;
+    compat::mem_ros::Subscriber<std_msgs_compat::String> feeder_notif_sub_;
+
+    void publish(const std::string& str, mementar::compat::mem_ros::Time stamp = compat::mem_ros::Node::get().currentTime());
+    void publish(const std::string& str, time_t end_stamp);
 
-    void publish(const std::string& str, time_t stamp = time(nullptr));
+    void feederNotificationCallback(const compat::mem_ros::MessageWrapper<std_msgs_compat::String>& msg);
   };
 
 } // namespace mementar
diff --git a/include/mementar/API/mementar/OccasionsSubscriber.h b/include/mementar/API/mementar/OccasionsSubscriber.h
index 6854098..27209cf 100644
--- a/include/mementar/API/mementar/OccasionsSubscriber.h
+++ b/include/mementar/API/mementar/OccasionsSubscriber.h
@@ -14,8 +14,7 @@ namespace mementar {
   class OccasionsSubscriber
   {
   public:
-    OccasionsSubscriber(const std::function<void(const Fact&)>& callback, const std::string& name = "", bool spin_thread = true);
-    OccasionsSubscriber(const std::function<void(const Fact&)>& callback, bool spin_thread);
+    OccasionsSubscriber(const std::function<void(const Fact&)>& callback, const std::string& name = "");
     ~OccasionsSubscriber();
 
     bool subscribe(const Fact& pattern, size_t count = -1);
diff --git a/include/mementar/RosInterface.h b/include/mementar/RosInterface.h
index d45e5bb..4923f90 100644
--- a/include/mementar/RosInterface.h
+++ b/include/mementar/RosInterface.h
@@ -62,7 +62,6 @@ namespace mementar {
     void ontoStampedKnowledgeCallback(const compat::mem_ros::MessageWrapper<ontologenius::compat::OntologeniusStampedString>& msg);
     void ontoExplanationKnowledgeCallback(const compat::mem_ros::MessageWrapper<ontologenius::compat::OntologeniusExplanation>& msg);
 
-    // todo: do not return bool
     bool managerInstanceHandle(compat::mem_ros::ServiceWrapper<compat::MementarService::Request>& req,
                                compat::mem_ros::ServiceWrapper<compat::MementarService::Response>& res);
 
diff --git a/include/mementar/compat/ros.h b/include/mementar/compat/ros.h
index fed1597..8061143 100644
--- a/include/mementar/compat/ros.h
+++ b/include/mementar/compat/ros.h
@@ -80,8 +80,6 @@ namespace mementar::compat {
   template<typename T, typename Response_ = typename T::Response>
   inline auto makeResponse() { return Response_(); }
 
-  // todo: RequestType, ResponseType
-
 #elif MEME_ROS_VERSION == 2
   using namespace ::mementar::msg;
   using namespace ::mementar::srv;
@@ -253,8 +251,6 @@ namespace mementar::compat {
       {
         auto& node = Node::get();
 
-        printf("[Publisher '%s'] Create\n", topic_name.c_str());
-
 #if MEME_ROS_VERSION == 1
         handle_ = node.handle_.advertise<T>(topic_name, queue_size);
 #elif MEME_ROS_VERSION == 2
@@ -265,8 +261,6 @@ namespace mementar::compat {
 
       void publish(const T& message)
       {
-        printf("[Publisher '%s'] Create\n", name_.c_str());
-
 #if MEME_ROS_VERSION == 1
         handle_.publish(message);
 #elif MEME_ROS_VERSION == 2
@@ -302,8 +296,6 @@ namespace mementar::compat {
       {
         auto& node = Node::get();
 
-        printf("[Subscriber '%s'] Create\n", topic_name.c_str());
-
 #if MEME_ROS_VERSION == 1
         handle_ = node.handle_.subscribe(topic_name, queue_size, callback, ptr);
 #elif MEME_ROS_VERSION == 2
@@ -331,8 +323,6 @@ namespace mementar::compat {
       {
         auto& node = Node::get();
 
-        printf("[Service '%s'] Create\n", service_name.c_str());
-
 #if MEME_ROS_VERSION == 1
         handle_ = node.handle_.advertiseService(service_name, callback);
 #elif MEME_ROS_VERSION == 2
@@ -352,8 +342,6 @@ namespace mementar::compat {
       {
         auto& node = Node::get();
 
-        printf("[Service '%s'] Create\n", service_name.c_str());
-
 #if MEME_ROS_VERSION == 1
         handle_ = node.handle_.advertiseService(service_name, callback, ptr);
 #elif MEME_ROS_VERSION == 2
@@ -388,8 +376,6 @@ namespace mementar::compat {
       {
         auto& node = Node::get();
 
-        printf("[Client '%s'] Create\n", service_name.c_str());
-
 #if MEME_ROS_VERSION == 1
         handle_ = node.handle_.serviceClient<T>(service_name, true);
 #elif MEME_ROS_VERSION == 2
@@ -399,8 +385,6 @@ namespace mementar::compat {
 
       RosStatus_e call(const mementar::compat::RequestType<T>& req, mementar::compat::ResponseType<T>& res)
       {
-        printf("[Client '%s'] Call\n", name_.c_str());
-
         using namespace std::chrono_literals;
         auto status = RosStatus_e::ros_status_failure;
 
@@ -442,7 +426,6 @@ namespace mementar::compat {
 
       bool wait(double timeout)
       {
-        printf("[Client '%s'] Wait\n", name_.c_str());
 #if MEME_ROS_VERSION == 1
         return handle_.waitForExistence(ros::Duration(timeout));
 #elif MEME_ROS_VERSION == 2
diff --git a/include/mementar/graphical/mementarGUI/mementargui.h b/include/mementar/graphical/mementarGUI/mementargui.h
index 94cf85a..044999a 100644
--- a/include/mementar/graphical/mementarGUI/mementargui.h
+++ b/include/mementar/graphical/mementarGUI/mementargui.h
@@ -8,7 +8,7 @@
 
 #include "include/mementar/graphical/mementarGUI/CallBackTimer.h"
 #include "include/mementar/graphical/mementarGUI/QCheckBoxExtended.h"
-#include "mementar/API/mementar/TimelineManipulator.h"
+#include "mementar/API/mementar/TimelinesManipulator.h"
 #include "mementar/compat/ros.h"
 
 namespace Ui { // NOLINT
@@ -30,11 +30,10 @@ class MementarGUI : public QMainWindow
 private:
   Ui::MementarGUI* ui_;
 
-  mementar::TimelineManipulator meme_;
+  mementar::TimelinesManipulator timelines_;
+  mementar::TimelineManipulator* timeline_;
+  bool multi_usage_;
 
-  std::map<std::string, std::unique_ptr<mementar::compat::mem_ros::Publisher<mementar::compat::StampedString>>> facts_publishers_;
-  std::map<std::string, std::unique_ptr<mementar::compat::mem_ros::Publisher<mementar::compat::MementarAction>>> actions_publishers_;
-  std::map<std::string, std::unique_ptr<mementar::compat::mem_ros::Subscriber<std_msgs_compat::String>>> feeder_notifications_subs_;
   std::string feeder_notifications_;
 
   int time_source_;
@@ -74,15 +73,17 @@ public slots:
   void timesourceChangedSlot(int index);
   void currentTimeEditingFinishedSlot();
 
-  void feederCallback(const std_msgs_compat::String& msg);
+  void feederCallback(const std::string& msg);
   void feederAddSlot();
   void feederDelSlot();
   void feederCommitSlot();
   void feederCheckoutSlot();
-  void createPublisher(const std::string& instance_ns);
+
+  bool updateTimelinePtr();
 
 signals:
-  void feederSetHtmlSignal(QString);
+  void feederSetHtmlSignal(QString t1);
+  void feederScrollSignal(QString t1);
   void setTimeSignal(QString);
 };
 
diff --git a/src/API/mementar/ActionsPublisher.cpp b/src/API/mementar/ActionsPublisher.cpp
index f003903..9d9eb55 100644
--- a/src/API/mementar/ActionsPublisher.cpp
+++ b/src/API/mementar/ActionsPublisher.cpp
@@ -7,7 +7,10 @@
 
 namespace mementar {
 
-  ActionsPublisher::ActionsPublisher(const std::string& name) : pub_(name.empty() ? "mementar/insert_action" : "mementar/insert_action/" + name, 1000) {}
+  ActionsPublisher::ActionsPublisher(const std::string& name) : feeder_notification_callback_([](auto& msg) { (void)msg; }),
+                                                                pub_(name.empty() ? "mementar/insert_action" : "mementar/insert_action/" + name, 1000),
+                                                                feeder_notif_sub_(name.empty() ? "mementar/feeder_notifications" : "mementar/feeder_notifications/" + name, 1000, &ActionsPublisher::feederNotificationCallback, this)
+  {}
 
   void ActionsPublisher::insert(const std::string& name, time_t start_stamp, time_t end_stamp)
   {
@@ -49,4 +52,9 @@ namespace mementar {
     pub_.publish(msg);
   }
 
+  void ActionsPublisher::feederNotificationCallback(const compat::mem_ros::MessageWrapper<std_msgs_compat::String>& msg)
+  {
+    feeder_notification_callback_(msg->data);
+  }
+
 } // namespace mementar
diff --git a/src/API/mementar/ActionsSubscriber.cpp b/src/API/mementar/ActionsSubscriber.cpp
index e12f99f..6890073 100644
--- a/src/API/mementar/ActionsSubscriber.cpp
+++ b/src/API/mementar/ActionsSubscriber.cpp
@@ -10,15 +10,8 @@
 namespace mementar {
 
   ActionsSubscriber::ActionsSubscriber(const std::function<void(const std::string&)>& callback,
-                                       const std::string& name,
-                                       bool spin_thread)
-    : OccasionsSubscriber([this](const Fact& fact) { this->privateCallback(fact); }, name, spin_thread),
-      callback_(callback)
-  {}
-
-  ActionsSubscriber::ActionsSubscriber(const std::function<void(const std::string&)>& callback,
-                                       bool spin_thread)
-    : OccasionsSubscriber([this](const Fact& fact) { this->privateCallback(fact); }, spin_thread),
+                                       const std::string& name)
+    : OccasionsSubscriber([this](const Fact& fact) { this->privateCallback(fact); }, name),
       callback_(callback)
   {}
 
diff --git a/src/API/mementar/OccasionsPublisher.cpp b/src/API/mementar/OccasionsPublisher.cpp
index 22a7275..514897a 100644
--- a/src/API/mementar/OccasionsPublisher.cpp
+++ b/src/API/mementar/OccasionsPublisher.cpp
@@ -4,23 +4,46 @@
 #include <string>
 
 #include "mementar/API/mementar/Fact.h"
+#include "mementar/compat/ros.h"
 
 namespace mementar {
 
-  OccasionsPublisher::OccasionsPublisher(const std::string& name)
-    : pub_((name.empty()) ? "mementar/insert_fact_stamped" : "mementar/insert_fact_stamped/" + name, 1000) {}
+  OccasionsPublisher::OccasionsPublisher(const std::string& name) : feeder_notification_callback_([](auto& msg) { (void)msg; }),
+                                                                    pub_((name.empty()) ? "mementar/insert_fact_stamped" : "mementar/insert_fact_stamped/" + name, 1000),
+                                                                    feeder_notif_sub_(name.empty() ? "mementar/feeder_notifications" : "mementar/feeder_notifications/" + name, 1000, &OccasionsPublisher::feederNotificationCallback, this)
+  {}
+
+  void OccasionsPublisher::insert(const Fact& fact, compat::mem_ros::Time stamp)
+  {
+    publish(fact(), stamp);
+  }
 
   void OccasionsPublisher::insert(const Fact& fact, time_t stamp)
   {
     publish(fact(), stamp);
   }
 
+  void OccasionsPublisher::publish(const std::string& str, compat::mem_ros::Time stamp)
+  {
+    compat::StampedString msg;
+    msg.data = str;
+    msg.stamp.seconds = stamp.seconds();
+    msg.stamp.nanoseconds = stamp.nanoseconds();
+    pub_.publish(msg);
+  }
+
   void OccasionsPublisher::publish(const std::string& str, time_t stamp)
   {
     compat::StampedString msg;
     msg.data = str;
     msg.stamp.seconds = stamp;
+    msg.stamp.nanoseconds = 0;
     pub_.publish(msg);
   }
 
+  void OccasionsPublisher::feederNotificationCallback(const compat::mem_ros::MessageWrapper<std_msgs_compat::String>& msg)
+  {
+    feeder_notification_callback_(msg->data);
+  }
+
 } // namespace mementar
diff --git a/src/API/mementar/OccasionsSubscriber.cpp b/src/API/mementar/OccasionsSubscriber.cpp
index fe3181a..3ba5693 100644
--- a/src/API/mementar/OccasionsSubscriber.cpp
+++ b/src/API/mementar/OccasionsSubscriber.cpp
@@ -10,35 +10,16 @@
 
 namespace mementar {
 
-  OccasionsSubscriber::OccasionsSubscriber(const std::function<void(const Fact&)>& callback, const std::string& name, bool spin_thread)
+  OccasionsSubscriber::OccasionsSubscriber(const std::function<void(const Fact&)>& callback, const std::string& name)
     : sub_(name.empty() ? "mementar/occasions" : "mementar/occasions/" + name, 1000, &OccasionsSubscriber::occasionCallback, this),
       client_subscribe_(name.empty() ? "mementar/subscribe" : "mementar/subscribe/" + name),
       client_cancel_(name.empty() ? "mementar/unsubscribe" : "mementar/unsubscribe/" + name),
       callback_(callback)
-  {
-    (void)spin_thread;
-
-    /*if (spin_thread) {
-        need_to_terminate_ = false;
-        spin_thread_ = std::thread(std::bind(&OccasionsSubscriber::spinThread, this));
-    } else {
-        spin_thread_ = {};
-    }*/
-  }
-
-  OccasionsSubscriber::OccasionsSubscriber(const std::function<void(const Fact&)>& callback, bool spin_thread)
-    : OccasionsSubscriber(callback, "", spin_thread) {}
+  {}
 
   OccasionsSubscriber::~OccasionsSubscriber()
   {
     cancel();
-    // todo
-    // sub_.shutdown();
-    /*if (spin_thread_) {
-        need_to_terminate_ = true;
-        spin_thread_->join();
-        delete spin_thread_;
-    }*/
   }
 
   bool OccasionsSubscriber::subscribe(const Fact& pattern, size_t count)
diff --git a/src/RosInterface.cpp b/src/RosInterface.cpp
index 6c2ea85..7b1de9e 100644
--- a/src/RosInterface.cpp
+++ b/src/RosInterface.cpp
@@ -115,15 +115,12 @@ namespace mementar {
     std::thread occasions_thread(&OccasionsManager::run, &occasions_);
     std::thread feed_thread(&RosInterface::feedThread, this);
 
-    // ROS_DEBUG("%s mementar ready", name_.c_str());
-
-    while(compat::mem_ros::Node::ok() && isRunning())
-    {
-      // todo
-      // ros::getGlobalCallbackQueue()->callAvailable(ros::WallDuration(0.1));
-    }
+    if(name_.empty() == false)
+      Display::info("Mementar " + name_ + " is ready");
+    else
+      Display::info("Mementar is ready");
 
-    occasions_.stop();
+    // occasions_.stop(); // todo verify
     occasions_thread.join();
     feed_thread.join();
   }
diff --git a/src/graphical/mementarGUI/mementargui.cpp b/src/graphical/mementarGUI/mementargui.cpp
index a8ff2c6..ce8a3d9 100644
--- a/src/graphical/mementarGUI/mementargui.cpp
+++ b/src/graphical/mementarGUI/mementargui.cpp
@@ -93,6 +93,7 @@ MementarGUI::MementarGUI(QWidget* parent) : QMainWindow(parent), ui_(new Ui::Mem
   QObject::connect(ui_->static_tab_widget, SIGNAL(currentChanged(int)), this, SLOT(currentTabChangedSlot(int)));
 
   QObject::connect(this, SIGNAL(feederSetHtmlSignal(QString)), ui_->feeder_info_edittext, SLOT(setHtml(QString)), Qt::BlockingQueuedConnection);
+  QObject::connect(this, SIGNAL(feederScrollSignal(QString)), ui_->feeder_info_edittext, SLOT(scrollToAnchor(QString)), Qt::BlockingQueuedConnection);
   QObject::connect(this, SIGNAL(setTimeSignal(QString)), ui_->static_current_time_editline, SLOT(setText(QString)), Qt::BlockingQueuedConnection);
   QObject::connect(ui_->static_current_time_editline, SIGNAL(editingFinished()), this, SLOT(currentTimeEditingFinishedSlot()));
 }
@@ -106,9 +107,18 @@ void MementarGUI::init()
 {
   timesourceChangedSlot(0);
 
-  facts_publishers_["_"] = std::make_unique<mementar::compat::mem_ros::Publisher<mementar::compat::StampedString>>("/mementar/insert_fact_stamped", QUEU_SIZE);
-  actions_publishers_["_"] = std::make_unique<mementar::compat::mem_ros::Publisher<mementar::compat::MementarAction>>("/mementar/insert_action", QUEU_SIZE);
-  feeder_notifications_subs_["_"] = std::make_unique<mementar::compat::mem_ros::Subscriber<std_msgs_compat::String>>("mementar/feeder_notifications", QUEU_SIZE, &MementarGUI::feederCallback, this);
+  if(timelines_.waitInit(1) == false)
+  {
+    timeline_ = new mementar::TimelineManipulator();
+    timeline_->action_feeder_.registerFeederNotificationCallback([this](auto msg) { this->feederCallback(msg); });
+    timeline_->fact_feeder_.registerFeederNotificationCallback([this](auto msg) { this->feederCallback(msg); });
+    multi_usage_ = false;
+  }
+  else
+  {
+    timeline_ = nullptr;
+    multi_usage_ = true;
+  }
 }
 
 void MementarGUI::wait()
@@ -153,20 +163,24 @@ void MementarGUI::factButtonHoverLeaveSlot()
 
 void MementarGUI::actionButtonClickedSlot()
 {
-  auto service_name = ui_->static_instance_name_editline->text().toStdString();
-
-  mementar::ActionClient client(service_name);
+  if(ui_->static_instance_name_editline->text().toStdString().find('=') != std::string::npos)
+  {
+    displayErrorInfo("Instance name cannot have the symbol = : \'" + ui_->static_instance_name_editline->text().toStdString() + "\'\n Once an instance copy has been performed, use the new instance name.");
+    return;
+  }
 
-  auto q_text = dynamic_cast<QPushButtonExtended*>(sender())->text();
-  auto q_param = ui_->action_parameter_editline->text();
+  const std::string action = dynamic_cast<QPushButtonExtended*>(sender())->text().toStdString();
+  const std::string param = ui_->action_parameter_editline->text().toStdString();
+  if(updateTimelinePtr() == false)
+    return;
 
-  QString text = q_text + " : " + ui_->action_parameter_editline->text();
+  const QString text = dynamic_cast<QPushButtonExtended*>(sender())->text() + " : " + ui_->action_parameter_editline->text();
   ui_->action_description_textedit->setText(text);
 
-  auto response = client.call(q_text.toStdString(), q_param.toStdString());
-  const int err = client.getErrorCode();
+  auto response = timeline_->actions_.call(action, param);
+  const int err = timeline_->actions_.getErrorCode();
   if(err == -1)
-    displayErrorInfo(service_name + " client call failed");
+    displayErrorInfo("client call failed");
   else
   {
     start();
@@ -181,20 +195,25 @@ void MementarGUI::actionButtonClickedSlot()
 
 void MementarGUI::factButtonClickedSlot()
 {
-  std::string service_name = ui_->static_instance_name_editline->text().toStdString();
-
-  mementar::FactClient client(service_name);
+  if(ui_->static_instance_name_editline->text().toStdString().find('=') != std::string::npos)
+  {
+    displayErrorInfo("Instance name cannot have the symbol = : \'" + ui_->static_instance_name_editline->text().toStdString() + "\'\n Once an instance copy has been performed, use the new instance name.");
+    return;
+  }
 
-  auto q_text = dynamic_cast<QPushButtonExtended*>(sender())->text();
-  auto q_param = ui_->fact_parameter_editline->text();
+  const std::string action = dynamic_cast<QPushButtonExtended*>(sender())->text().toStdString();
+  const std::string param = ui_->fact_parameter_editline->text().toStdString();
+  if(updateTimelinePtr() == false)
+    return;
 
-  QString text = q_text + " : " + ui_->fact_parameter_editline->text();
+  const QString text = dynamic_cast<QPushButtonExtended*>(sender())->text() + " : " + ui_->fact_parameter_editline->text();
   ui_->fact_description_textedit->setText(text);
 
-  auto response = client.call(q_text.toStdString(), q_param.toStdString());
-  const int err = client.getErrorCode();
+  auto response = timeline_->facts_.call(action, param);
+  const int err = timeline_->facts_.getErrorCode();
+
   if(err == -1)
-    displayErrorInfo(service_name + " client call failed");
+    displayErrorInfo("client call failed");
   else
   {
     start();
@@ -209,6 +228,8 @@ void MementarGUI::factButtonClickedSlot()
 
 void MementarGUI::nameEditingFinishedSlot()
 {
+  if(updateTimelinePtr() == false)
+    return;
 }
 
 void MementarGUI::displayErrorInfo(const std::string& text)
@@ -225,11 +246,12 @@ void MementarGUI::displayErrorInfo(const std::string& text)
 
 void MementarGUI::displayInstancesList()
 {
-  auto values = meme_.manager_.list();
+  auto res_vect = timelines_.list();
+  const int err = timelines_.getErrorCode();
 
   std::string html;
 
-  if(meme_.manager_.getErrorCode() == -1)
+  if(err == -1)
   {
     html = "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0//EN\" \"http://www.w3.org/TR/REC-html40/strict.dtd\">"
            "<html><head><meta name=\"qrichtext\" content=\"1\" /><style type=\"text/css\">"
@@ -239,7 +261,7 @@ void MementarGUI::displayInstancesList()
   }
   else
   {
-    std::string text = vector2html(values);
+    std::string text = vector2html(res_vect);
     html = "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0//EN\" \"http://www.w3.org/TR/REC-html40/strict.dtd\">"
            "<html><head><meta name=\"qrichtext\" content=\"1\" /><style type=\"text/css\">"
            "p, li { white-space: pre-wrap; }"
@@ -272,7 +294,7 @@ std::string MementarGUI::vector2html(const std::vector<std::string>& vect)
   return res;
 }
 
-void MementarGUI::updateTime()
+void MementarGUI::updateTime() // todo fix time display
 {
   if(time_source_ == 0)
   {
@@ -304,9 +326,8 @@ void MementarGUI::currentTabChangedSlot(int tab_id)
 
 void MementarGUI::addInstanceSlot()
 {
-  bool do_copy = false;
-
   std::string param = ui_->manager_instance_name_editline->text().toStdString();
+  std::string inst_name = param;
 
   std::regex base_regex("(.*)=(.*)");
   std::smatch base_match;
@@ -314,78 +335,41 @@ void MementarGUI::addInstanceSlot()
   {
     if(base_match.size() == 3)
     {
-      do_copy = true;
-
-      if(facts_publishers_.find(base_match[1].str()) == facts_publishers_.end())
-      {
-        facts_publishers_[base_match[1].str()] = std::make_unique<mementar::compat::mem_ros::Publisher<mementar::compat::StampedString>>(
-          "mementar/insert_fact_stamped/" + base_match[1].str(), QUEU_SIZE);
-
-        actions_publishers_[base_match[1].str()] = std::make_unique<mementar::compat::mem_ros::Publisher<mementar::compat::MementarAction>>(
-          "mementar/insert_action/" + base_match[1].str(), QUEU_SIZE);
-      }
-
-      if(feeder_notifications_subs_.find(base_match[1].str()) == feeder_notifications_subs_.end())
-        feeder_notifications_subs_[base_match[1].str()] = std::make_unique<mementar::compat::mem_ros::Subscriber<std_msgs_compat::String>>(
-          "mementar/feeder_notifications", QUEU_SIZE, &MementarGUI::feederCallback, this);
+      ui_->static_result_editext->setText(QString::fromStdString("Copy is not yet supported."));
+      return;
+      // timelines_.copy(base_match[1].str(), base_match[2].str());
+      // inst_name = base_match[1].str();
     }
   }
   else
-  {
-    if(facts_publishers_.find(param) == facts_publishers_.end())
-    {
-      facts_publishers_[param] = std::make_unique<mementar::compat::mem_ros::Publisher<mementar::compat::StampedString>>(
-        "mementar/insert_fact_stamped/" + param, QUEU_SIZE);
-      actions_publishers_[param] = std::make_unique<mementar::compat::mem_ros::Publisher<mementar::compat::MementarAction>>(
-        "mementar/insert_action/" + param, QUEU_SIZE);
-    }
-
-    if(feeder_notifications_subs_.find(param) == feeder_notifications_subs_.end())
-      feeder_notifications_subs_[param] = std::make_unique<mementar::compat::mem_ros::Subscriber<std_msgs_compat::String>>(
-        "mementar/feeder_notifications", QUEU_SIZE, &MementarGUI::feederCallback, this);
-  }
-
-  if(do_copy)
-    meme_.manager_.copy(param);
-  else
-    meme_.manager_.add(param);
-
-  auto err = meme_.manager_.getErrorCode();
+    timelines_.add(param);
 
+  const int err = timelines_.getErrorCode();
   if(err == -1)
-  {
     displayErrorInfo("mementar/manage client call failed");
-    return;
-  }
-
-  switch(err)
-  {
-  case 1:
-  {
-    ui_->static_result_editext->setText(QString::fromStdString("fail to stop " + param + " : please retry"));
-    break;
-  }
-  case 4:
-  {
-    ui_->static_result_editext->setText(QString::fromStdString(param + " already created"));
-    break;
-  }
-  default:
+  else
   {
-    ui_->static_result_editext->setText(QString::fromStdString(""));
-    break;
-  }
-  }
+    start();
+    if(err == 4)
+      ui_->static_result_editext->setText(QString::fromStdString(param + " already created"));
+    else if(err == 1)
+      ui_->static_result_editext->setText(QString::fromStdString("fail to stop " + param + " : please retry"));
+    else
+    {
+      ui_->static_result_editext->setText(QString::fromStdString(""));
+      timelines_.get(inst_name)->action_feeder_.registerFeederNotificationCallback([this](auto msg) { this->feederCallback(msg); });
+      timelines_.get(inst_name)->fact_feeder_.registerFeederNotificationCallback([this](auto msg) { this->feederCallback(msg); });
+    }
 
-  displayInstancesList();
+    displayInstancesList();
+  }
 }
 
 void MementarGUI::deleteInstanceSlot()
 {
   auto param = ui_->manager_instance_name_editline->text().toStdString();
-  meme_.manager_.del(ui_->manager_instance_name_editline->text().toStdString());
-
-  auto err = meme_.manager_.getErrorCode();
+  timelines_.del(param);
+  const int err = timelines_.getErrorCode();
 
   if(err == -1)
   {
@@ -394,75 +378,81 @@ void MementarGUI::deleteInstanceSlot()
   }
 
   start();
-
   if(err == 4)
-  {
     ui_->static_result_editext->setText(QString::fromStdString("Instance \'" + param + "\' don't exist"));
-  }
   else
-  {
     ui_->static_result_editext->setText(QString::fromStdString(""));
-  }
-
   displayInstancesList();
 }
 
 void MementarGUI::saveInstanceSlot()
 {
-  auto service_name = ui_->manager_instance_name_editline->text().toStdString();
-  auto param = ui_->manager_save_path_editline->text().toStdString();
+  if(ui_->manager_instance_name_editline->text().toStdString().find('=') != std::string::npos)
+  {
+    displayErrorInfo("Instance name cannot have the symbol = : \'" + ui_->manager_instance_name_editline->text().toStdString() + "\'\n Once an instance copy has been performed, use the new instance name.");
+    return;
+  }
 
-  mementar::InstanceManagerClient client(service_name);
+  if(updateTimelinePtr() == false)
+    return;
 
-  client.save(ui_->manager_save_path_editline->text().toStdString());
-  auto err = client.getErrorCode();
+  auto param = ui_->manager_save_path_editline->text().toStdString();
+  timeline_->inst_manager_.save(param);
+  const int err = timeline_->inst_manager_.getErrorCode();
 
   if(err == -1)
   {
     displayErrorInfo("mementar/manage_instance client call failed");
     return;
   }
-
-  if(err == 4)
-  {
-    ui_->static_result_editext->setText(QString::fromStdString("path \'" + param + "\' don't exist"));
-  }
   else
   {
-    ui_->static_result_editext->setText(QString::fromStdString(""));
+    if(err == 4)
+      ui_->static_result_editext->setText(QString::fromStdString("path \'" + param + "\' don't exist"));
+    else
+      ui_->static_result_editext->setText(QString::fromStdString(""));
   }
 }
 
 void MementarGUI::drawInstanceSlot()
 {
-  auto service_name = ui_->manager_instance_name_editline->text().toStdString();
-  auto param = ui_->manager_draw_path_editline->text().toStdString();
+  if(ui_->manager_instance_name_editline->text().toStdString().find('=') != std::string::npos)
+  {
+    displayErrorInfo("Instance name cannot have the symbol = : \'" + ui_->manager_instance_name_editline->text().toStdString() + "\'\n Once an instance copy has been performed, use the new instance name.");
+    return;
+  }
 
-  mementar::InstanceManagerClient client(service_name);
+  if(updateTimelinePtr() == false)
+    return;
 
-  client.draw(ui_->manager_save_path_editline->text().toStdString());
-  auto err = client.getErrorCode();
+  auto param = ui_->manager_save_path_editline->text().toStdString();
+  timeline_->inst_manager_.draw(param);
+  const int err = timeline_->inst_manager_.getErrorCode();
 
   if(err == -1)
   {
     displayErrorInfo("mementar/manage_instance client call failed");
     return;
   }
-
-  if(err == 4)
-  {
-    ui_->static_result_editext->setText(QString::fromStdString("path \'" + param + "\' don't exist"));
-  }
   else
   {
-    ui_->static_result_editext->setText(QString::fromStdString(""));
+    if(err == 4)
+      ui_->static_result_editext->setText(QString::fromStdString("path \'" + param + "\' don't exist"));
+    else
+      ui_->static_result_editext->setText(QString::fromStdString(""));
   }
 }
 
 void MementarGUI::instanceNameAddDelChangedSlot(const QString& text)
 {
   if(ui_->static_instance_name_editline->text() != text)
-    ui_->static_instance_name_editline->setText(text);
+  {
+    const size_t equal_pose = text.toStdString().find('=');
+    if(equal_pose != std::string::npos)
+      ui_->static_instance_name_editline->setText(text.mid(0, (int)equal_pose));
+    else
+      ui_->static_instance_name_editline->setText(text);
+  }
 }
 
 void MementarGUI::instanceNameChangedSlot(const QString& text)
@@ -516,25 +506,26 @@ void MementarGUI::currentTimeEditingFinishedSlot()
   }
 }
 
-void MementarGUI::feederCallback(const std_msgs_compat::String& msg)
+void MementarGUI::feederCallback(const std::string& msg)
 {
-  feeder_notifications_ += "<p>-" + msg.data + "</p>";
+  feeder_notifications_ += "<p>-" + msg + "</p>";
 
-  std::string html =
-    "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0//EN\" \"http://www.w3.org/TR/REC-html40/strict.dtd\">"
-    "<html><head><meta name=\"qrichtext\" content=\"1\" /><style type=\"text/css\">"
-    "p, li { whicommitte-space: pre-wrap; }"
-    "</style></head><body style=\" font-family:'Noto Sans'; font-size:9pt; font-weight:400; font-style:normal;\">"
-    "<p align=\"left\" style=\" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;\"><span style=\" font-size:12pt; \">" +
-    feeder_notifications_ + "<br></span></p></body></html>";
+  const std::string html = "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0//EN\" \"http://www.w3.org/TR/REC-html40/strict.dtd\">"
+                           "<html><head><meta name=\"qrichtext\" content=\"1\" /><style type=\"text/css\">"
+                           "p, li { whicommitte-space: pre-wrap; }"
+                           "</style></head><body style=\" font-family:'Noto Sans'; font-size:9pt; font-weight:400; font-style:normal;\">"
+                           "<p align=\"left\" style=\" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;\"><span style=\" font-size:12pt; \">" +
+                           feeder_notifications_ + R"(<a name="scrollToMe" href="#scroll"></a> <br></span></p></body></html>)";
 
-  ui_->feeder_info_edittext->moveCursor(QTextCursor::End);
   feederSetHtmlSignal(QString::fromStdString(html));
-  ui_->feeder_info_edittext->ensureCursorVisible();
+  feederScrollSignal("scrollToMe");
 }
 
 void MementarGUI::feederAddSlot()
 {
+  if(updateTimelinePtr() == false)
+    return;
+
   std::string subject = ui_->feeder_subject_editline->text().toStdString();
   std::string predicat = ui_->feeder_property_editline->text().toStdString();
   std::string object = ui_->feeder_object_editline->text().toStdString();
@@ -545,31 +536,21 @@ void MementarGUI::feederAddSlot()
   }
   else
   {
-    std::string instance_ns = ui_->static_instance_name_editline->text().toStdString();
-    if(instance_ns.empty())
-      instance_ns = "_";
-    createPublisher(instance_ns);
     if((predicat.empty()) && (object.empty()))
-    {
-      mementar::compat::MementarAction msg;
-      msg.name = subject;
-      msg.start_stamp = current_time_;
-      msg.end_stamp.seconds = 0;
-      msg.end_stamp.nanoseconds = 0;
-      actions_publishers_[instance_ns]->publish(msg);
-    }
+      timeline_->action_feeder_.insert(subject, mementar::compat::mem_ros::Time(current_time_.seconds, current_time_.nanoseconds));
     else
     {
-      mementar::compat::StampedString msg;
-      msg.data = "[ADD]" + subject + "|" + predicat + "|" + object;
-      msg.stamp = current_time_;
-      facts_publishers_[instance_ns]->publish(msg);
+      mementar::Fact fact(subject, predicat, object, true);
+      timeline_->fact_feeder_.insert(fact, mementar::compat::mem_ros::Time(current_time_.seconds, current_time_.nanoseconds));
     }
   }
 }
 
 void MementarGUI::feederDelSlot()
 {
+  if(updateTimelinePtr() == false)
+    return;
+
   std::string subject = ui_->feeder_subject_editline->text().toStdString();
   std::string predicat = ui_->feeder_property_editline->text().toStdString();
   std::string object = ui_->feeder_object_editline->text().toStdString();
@@ -580,74 +561,54 @@ void MementarGUI::feederDelSlot()
   }
   else
   {
-    std::string instance_ns = ui_->static_instance_name_editline->text().toStdString();
-    if(instance_ns.empty())
-      instance_ns = "_";
-    createPublisher(instance_ns);
     if((predicat.empty()) && (object.empty()))
-    {
-      mementar::compat::MementarAction msg;
-      msg.name = subject;
-      msg.start_stamp.seconds = 0;
-      msg.start_stamp.nanoseconds = 0;
-      msg.end_stamp = current_time_;
-      actions_publishers_[instance_ns]->publish(msg);
-    }
+      timeline_->action_feeder_.insertEnd(subject, mementar::compat::mem_ros::Time(current_time_.seconds, current_time_.nanoseconds));
     else
     {
-      mementar::compat::StampedString msg;
-      msg.data = "[DEL]" + subject + "|" + predicat + "|" + object;
-      msg.stamp = current_time_;
-      facts_publishers_[instance_ns]->publish(msg);
+      mementar::Fact fact(subject, predicat, object, false);
+      timeline_->fact_feeder_.insert(fact, mementar::compat::mem_ros::Time(current_time_.seconds, current_time_.nanoseconds));
     }
   }
 }
 
 void MementarGUI::feederCommitSlot()
 {
-  mementar::compat::StampedString msg;
-  msg.data = "[commit]" + ui_->feeder_commit_name_editline->text().toStdString() + "|";
-  std::string instance_ns = ui_->static_instance_name_editline->text().toStdString();
-  if(instance_ns.empty())
-    instance_ns = "_";
-  createPublisher(instance_ns);
-  facts_publishers_[instance_ns]->publish(msg);
+  if(updateTimelinePtr() == false)
+    return;
+
+  // timeline_->fact_feeder_.commit(ui_->feeder_commit_name_editline->text().toStdString());
 }
 
 void MementarGUI::feederCheckoutSlot()
 {
-  mementar::compat::StampedString msg;
-  msg.data = "[checkout]" + ui_->feeder_commit_name_editline->text().toStdString() + "|";
-  std::string instance_ns = ui_->static_instance_name_editline->text().toStdString();
-  if(instance_ns.empty())
-    instance_ns = "_";
-  createPublisher(instance_ns);
-  facts_publishers_[instance_ns]->publish(msg);
+  if(updateTimelinePtr() == false)
+    return;
+
+  // timeline_->fact_feeder_.checkout(ui_->feeder_commit_name_editline->text().toStdString());
 }
 
-void MementarGUI::createPublisher(const std::string& instance_ns)
+bool MementarGUI::updateTimelinePtr()
 {
-  if(facts_publishers_.find(instance_ns) == facts_publishers_.end())
-  {
-    facts_publishers_[instance_ns] = std::make_unique<mementar::compat::mem_ros::Publisher<mementar::compat::StampedString>>(
-      "mementar/insert_fact_stamped/" + instance_ns, QUEU_SIZE);
+  if(multi_usage_ == false)
+    return true;
 
-    while(mementar::compat::mem_ros::Node::ok() && (facts_publishers_[instance_ns]->getNumSubscribers() == 0))
-    {
-      // todo
-      // ros::spinOnce();
-    }
-  }
-
-  if(actions_publishers_.find(instance_ns) == actions_publishers_.end())
+  const std::string instance_name = ui_->static_instance_name_editline->text().toStdString();
+  timeline_ = timelines_.get(instance_name);
+  if(timeline_ == nullptr)
   {
-    actions_publishers_[instance_ns] = std::make_unique<mementar::compat::mem_ros::Publisher<mementar::compat::MementarAction>>(
-      "mementar/insert_action/" + instance_ns, QUEU_SIZE);
-
-    while(mementar::compat::mem_ros::Node::ok() && (actions_publishers_[instance_ns]->getNumSubscribers() == 0))
+    auto intances_name = timelines_.list();
+    if(std::find(intances_name.begin(), intances_name.end(), instance_name) != intances_name.end())
     {
-      // todo
-      // ros::spinOnce();
+      timelines_.add(instance_name);
+      timeline_ = timelines_.get(instance_name);
+      if(timeline_ != nullptr)
+        return true;
     }
+
+    if(instance_name.empty() == false)
+      displayErrorInfo("Instance " + instance_name + " does not exist");
+    return false;
   }
+  else
+    return true;
 }