diff --git a/run.sh b/run.sh
index 0162783..97fbe28 100755
--- a/run.sh
+++ b/run.sh
@@ -9,7 +9,11 @@ python3 main.py \
     --dst-host=192.168.74.251 \
     --csvpool \
     --csvpool-file-path-prefix=qwe_ \
-    --csv-column-default-value date_1=2000-01-01 datetime_1=2000-01-01\ 01:02:03 time_1=2001-01-01\ 01:02:03 timestamp_1=2002-01-01\ 01:02:03 \
+    --csv-column-default-value \
+            date_1=2000-01-01 \
+            datetime_1=2000-01-01\ 01:02:03 \
+            time_1=2001-01-01\ 01:02:03 \
+            timestamp_1=2002-01-01\ 01:02:03 \
     --mempool-max-flush-interval=600 \
     --mempool-max-events-num=900000
 
diff --git a/src/cliopts.py b/src/cliopts.py
index 9d36566..561ca2b 100644
--- a/src/cliopts.py
+++ b/src/cliopts.py
@@ -9,8 +9,16 @@ class CLIOpts(object):
 
     @staticmethod
     def join(lists_to_join):
-        # lists_to_join contains something like
-        # [['a=b', 'c=d'], ['e=f', 'z=x'], ]
+        """Join several lists into one
+
+        :param lists_to_join: is a list of lists
+        [['a=b', 'c=d'], ['e=f', 'z=x'], ]
+
+        :return: None or dictionary
+        {'a': 'b', 'c': 'd', 'e': 'f', 'z': 'x'}
+
+        """
+
         if not isinstance(lists_to_join, list):
             return None
 
@@ -18,15 +26,16 @@ def join(lists_to_join):
         for lst in lists_to_join:
             # lst = ['a=b', 'c=d']
             for column_value_pair in lst:
-                # value = 'a=b'
+                # column_value_value = 'a=b'
                 column, value = column_value_pair.split('=', 2)
                 res[column] = value
 
-        # dict {
+        # res = dict {
         #   'col1': 'value1',
         #   'col2': 'value2',
         # }
 
+        # return with sanity check
         if len(res) > 0:
             return res
         else:
@@ -34,10 +43,10 @@ def join(lists_to_join):
 
     @staticmethod
     def config():
+        """Parse application's CLI options into options dictionary
+        :return: instance of Config
         """
-        parse CLI options into options dict
-        :return: dict
-        """
+
         argparser = argparse.ArgumentParser(
             description='ClickHouse data reader',
             epilog='==============='
diff --git a/src/converter/chwriteconverter.py b/src/converter/chwriteconverter.py
index 0499077..d4c3950 100644
--- a/src/converter/chwriteconverter.py
+++ b/src/converter/chwriteconverter.py
@@ -25,30 +25,28 @@ class CHWriteConverter(Converter):
         set,
     ]
 
-    def convert(self, event):
-
+    def row(self, row):
         columns_to_delete = []
 
-        for column in event.row:
-            if (event.row[column] is None) and self.delete_empty_columns:
+        for column in row:
+            if (row[column] is None) and self.delete_empty_columns:
                 # include empty column to the list of to be deleted columns
                 columns_to_delete.append(column)
                 # move to next column
                 continue
 
             for t in self.types_to_convert:
-                if isinstance(event.row[column], t):
-#                    print("Converting column", column, "of type", type(event.row[column]),
-#                          event.row[column])
-                    event.row[column] = str(event.row[column])
-#                    print("res", event.row[column])
+                if isinstance(row[column], t):
+                    # print("Converting column", column, "of type", type(event.row[column]), event.row[column])
+                    row[column] = str(row[column])
+                    # print("res", event.row[column])
                     break
             else:
-#                print("Using asis column", column, "of type", type(event.row[column]))
+                # print("Using asis column", column, "of type", type(event.row[column]))
                 pass
 
         # delete columns according to the list
         for column in columns_to_delete:
-            event.row.pop(column)
+            row.pop(column)
 
-        return event
+        return row
diff --git a/src/converter/converter.py b/src/converter/converter.py
index e398b9f..4020658 100644
--- a/src/converter/converter.py
+++ b/src/converter/converter.py
@@ -1,7 +1,31 @@
 #!/usr/bin/env python
 # -*- coding: utf-8 -*-
 
+from ..event.event import Event
+
+
 class Converter(object):
 
-    def convert(self, event):
+    def row(self, row):
+        return row
+
+    def rows(self, rows):
+        if rows is None:
+            return None
+
+        res = []
+        for row in rows:
+            res.append(self.row(row))
+
+        return res
+
+    def event(self, event):
+        event.row = self.row(event.row)
+        event.rows = self.rows(event.rows)
         return event
+
+    def convert(self, event_or_row):
+        if isinstance(event_or_row, Event):
+            return self.event(event_or_row)
+        else:
+            return self.row(event_or_row)
diff --git a/src/converter/csvreadconverter.py b/src/converter/csvreadconverter.py
index 70ab90d..ef3192f 100644
--- a/src/converter/csvreadconverter.py
+++ b/src/converter/csvreadconverter.py
@@ -7,13 +7,13 @@
 
 class CSVReadConverter(Converter):
 
-    def convert(self, event):
-        for column in event.row:
-            if event.row[column] == '':
-                event.row[column] = None
+    def row(self, row):
+        for column in row:
+            if row[column] == '':
+                row[column] = None
 #            else:
 #                try:
 #                    event.row[column] = ast.literal_eval(event.row[column])
 #                except:
 #                    pass
-        return event
+        return row
diff --git a/src/converter/csvwriteconverter.py b/src/converter/csvwriteconverter.py
index c820e14..a33a045 100644
--- a/src/converter/csvwriteconverter.py
+++ b/src/converter/csvwriteconverter.py
@@ -12,19 +12,20 @@ class CSVWriteConverter(Converter):
     def __init__(self, defaults=None):
         self.defaults = defaults
 
-    def convert(self, event):
+    def row(self, row):
+        for column in row:
+            if (row[column] is None) and (column in self.defaults):
+                row[column] = self.defaults[column]
+        return row
+
+    def convert(self, event_or_row):
         # no defaults - nothing to convert
         if not self.defaults:
-            return event
+            return event_or_row
 
         # defaults are empty - nothing to convert
         if len(self.defaults) < 1:
-            return event
+            return event_or_row
 
         # have defaults
-        for column in event.row:
-            # replace None column with default value
-            if event.row[column] is None and column in self.defaults:
-                event.row[column] = self.defaults[column]
-
-        return event
+        return super().convert(event_or_row)
diff --git a/src/event/event.py b/src/event/event.py
index 1e388a3..f1e502c 100644
--- a/src/event/event.py
+++ b/src/event/event.py
@@ -13,7 +13,23 @@ class Event(object):
     # {'id':1, 'col1':1}
     row = None
 
-    file = None
+    # [{'id': 1, 'col1':1}, {'id': 2, 'col1': 2}, {'id': 3, 'col1': 3}]
+    rows = None
+
+    # /path/to/csv/file.csv
+    filename = None
 
     # ['id', 'col1', 'col2']
-    fieldnames = None
\ No newline at end of file
+    fieldnames = None
+
+    def first(self):
+        if self.rows is None:
+            return self.row
+        else:
+            return self.rows[0]
+
+    def all(self):
+        if self.rows is None:
+            return [self.row]
+        else:
+            return self.rows
diff --git a/src/objectbuilder.py b/src/objectbuilder.py
index 08e6762..0a353fe 100644
--- a/src/objectbuilder.py
+++ b/src/objectbuilder.py
@@ -9,6 +9,14 @@ class ObjectBuilder(object):
     instance = None
 
     def __init__(self, class_name=None, constructor_params=None, instance=None):
+        """
+        Builder/Wrapper for ad object.
+        In case instance is provided - operates as a wrapper
+        In case class_name and (optional) constructor_params provided - return instance of specified class
+        :param class_name: class to instantiate
+        :param constructor_params: dict of class's contrcutor params. Used as **constructor_params
+        :param instance: ready-to use instance
+        """
         self.class_name = class_name
         self.constructor_params = constructor_params
         self.instance = instance
@@ -19,12 +27,39 @@ def param(self, name, value):
         self.constructor_params[name] = value
 
     def get(self):
+        """
+        Get object (in case wrapper) or an instance of a class (in case Object builder) - each time the same object
+        :return: object
+        """
         if not self.class_name:
             # no class name - return instance, it may be None
             return self.instance
 
         # have class name
 
+        # instantiate object
+        if self.constructor_params:
+            self.instance =  self.class_name(**self.constructor_params)
+        else:
+            self.instance = self.class_name()
+
+        # in order to return instance on next get() call
+        self.class_name = None
+
+        return self.instance
+
+    def new(self):
+        """
+        Get object (in case wrapper) or an instance of a class (in case Object builder) - each time new object
+        :return: object
+        """
+        if not self.class_name:
+            # no class name - return instance, it may be None
+            return self.instance
+
+        # have class name
+
+        # instantiate object
         if self.constructor_params:
             return self.class_name(**self.constructor_params)
         else:
diff --git a/src/observable.py b/src/observable.py
new file mode 100644
index 0000000..d8b9495
--- /dev/null
+++ b/src/observable.py
@@ -0,0 +1,28 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+
+class Observable(object):
+
+    event_handlers = {
+        'Event1': [],
+        'Event2': [],
+    }
+
+    def subscribe(self, event_handlers):
+        for event_name in event_handlers:
+            if event_name in self.event_handlers:
+                if callable(event_handlers[event_name]):
+                    self.event_handlers[event_name].append(event_handlers[event_name])
+                else:
+                    if isinstance(event_handlers[event_name], list):
+                        for callback in event_handlers[event_name]:
+                            if callable(callback):
+                                self.event_handlers[event_name].append(callback)
+
+    def notify(self, event_name, **attrs):
+        for callback in self.event_handlers[event_name]:
+            callback(**attrs)
+
+    def subscribers(self, event_name):
+        return event_name in self.event_handlers and (len(self.event_handlers[event_name]) > 0)
\ No newline at end of file
diff --git a/src/pumper.py b/src/pumper.py
index 03f5d31..97c5b32 100644
--- a/src/pumper.py
+++ b/src/pumper.py
@@ -16,7 +16,7 @@ def __init__(self, reader=None, writer=None):
         if self.reader:
             self.reader.subscribe({
                 'WriteRowsEvent': self.write_rows_event,
-                'WriteRowsEvent.EachRow': self.write_rows_event_each_row,
+#                'WriteRowsEvent.EachRow': self.write_rows_event_each_row,
                 'ReaderIdleEvent': self.reader_idle_event,
             })
 
@@ -24,8 +24,7 @@ def run(self):
         self.reader.read()
 
     def write_rows_event(self, event=None):
-#        binlog_event.dump()
-        pass
+        self.writer.insert(event)
 
     def write_rows_event_each_row(self, event=None):
         self.writer.insert(event)
diff --git a/src/reader/csvreader.py b/src/reader/csvreader.py
index e0a439e..09b53b4 100644
--- a/src/reader/csvreader.py
+++ b/src/reader/csvreader.py
@@ -41,10 +41,10 @@ def read(self):
         try:
             event = Event()
             event.table = os.path.splitext(self.csv_file_path)[0]
-            self.fire('WriteRowsEvent', event=event)
+            self.notify('WriteRowsEvent', event=event)
             for row in self.reader:
                 event.row = row
-                self.fire('WriteRowsEvent.EachRow', event=self.converter.convert(event) if self.converter else event)
+                self.notify('WriteRowsEvent.EachRow', event=self.converter.convert(event) if self.converter else event)
         except KeyboardInterrupt:
             pass
 
diff --git a/src/reader/mysqlreader.py b/src/reader/mysqlreader.py
index 88044db..ba13fef 100644
--- a/src/reader/mysqlreader.py
+++ b/src/reader/mysqlreader.py
@@ -69,16 +69,22 @@ def read(self):
             while True:
                 for mysql_event in self.binlog_stream:
                     if isinstance(mysql_event, WriteRowsEvent):
-                        event = Event()
-                        event.schema = mysql_event.schema
-                        event.table = mysql_event.table
-                        self.fire('WriteRowsEvent', event=event)
-                        for row in mysql_event.rows:
+                        if self.subscribers('WriteRowsEvent'):
                             event = Event()
                             event.schema = mysql_event.schema
                             event.table = mysql_event.table
-                            event.row = row['values']
-                            self.fire('WriteRowsEvent.EachRow', event=event)
+                            event.rows = []
+                            for row in mysql_event.rows:
+                                event.rows.append(row['values'])
+                            self.notify('WriteRowsEvent', event=event)
+
+                        if self.subscribers('WriteRowsEvent.EachRow'):
+                            for row in mysql_event.rows:
+                                event = Event()
+                                event.schema = mysql_event.schema
+                                event.table = mysql_event.table
+                                event.row = row['values']
+                                self.notify('WriteRowsEvent.EachRow', event=event)
                     else:
                         # skip non-insert events
                         pass
@@ -87,7 +93,7 @@ def read(self):
                     break
 
                 # blocking
-                self.fire('ReaderIdleEvent')
+                self.notify('ReaderIdleEvent')
 
         except KeyboardInterrupt:
             pass
diff --git a/src/reader/reader.py b/src/reader/reader.py
index 547edc1..23c27b2 100644
--- a/src/reader/reader.py
+++ b/src/reader/reader.py
@@ -1,12 +1,14 @@
 #!/usr/bin/env python
 # -*- coding: utf-8 -*-
 
+from ..observable import Observable
 
-class Reader(object):
+
+class Reader(Observable):
 
     converter = None
 
-    callbacks = {
+    event_handlers = {
         # called on each WriteRowsEvent
         'WriteRowsEvent': [],
 
@@ -21,14 +23,5 @@ def __init__(self, converter=None, callbacks={}):
         self.converter = converter
         self.subscribe(callbacks)
 
-    def subscribe(self, callbacks):
-        for callback_name in callbacks:
-            if callback_name in self.callbacks:
-                self.callbacks[callback_name].append(callbacks[callback_name])
-
-    def fire(self, event_name, **attrs):
-        for callback in self.callbacks[event_name]:
-            callback(**attrs)
-
     def read(self):
         pass
diff --git a/src/writer/chcsvwriter.py b/src/writer/chcsvwriter.py
index e350b2f..fd1900d 100644
--- a/src/writer/chcsvwriter.py
+++ b/src/writer/chcsvwriter.py
@@ -50,7 +50,7 @@ def insert(self, event_or_events=None):
             if self.password:
                 choptions += " --password=" + self.password
             bash = "tail -n +2 '{0}' | clickhouse-client {1} --query='{2}'".format(
-                event.file,
+                event.filename,
                 choptions,
                 sql,
             )
diff --git a/src/writer/chwriter.py b/src/writer/chwriter.py
index 4625e6d..fb18f07 100644
--- a/src/writer/chwriter.py
+++ b/src/writer/chwriter.py
@@ -43,7 +43,8 @@ def insert(self, event_or_events=None):
         event_converted = None
         for event in events:
             event_converted = self.convert(event)
-            values.append(event_converted.row)
+            for value in event_converted.all():
+                values.append(value)
 
         schema = self.dst_schema if self.dst_schema else event_converted.schema
         table = self.dst_table if self.dst_table else event_converted.table
diff --git a/src/writer/csvwriter.py b/src/writer/csvwriter.py
index 6ea1f04..9d4d392 100644
--- a/src/writer/csvwriter.py
+++ b/src/writer/csvwriter.py
@@ -76,7 +76,7 @@ def insert(self, event_or_events):
             self.open()
 
         if not self.writer:
-            self.fieldnames = sorted(events[0].row.keys())
+            self.fieldnames = sorted(events[0].first().keys())
             if self.dst_schema is None:
                 self.dst_schema = events[0].schema
             if self.dst_table is None:
@@ -87,7 +87,8 @@ def insert(self, event_or_events):
                 self.writer.writeheader()
 
         for event in events:
-            self.writer.writerow(self.convert(event).row)
+            for row in event.all():
+                self.writer.writerow(self.convert(row))
 
     def push(self):
         if not self.next_writer_builder:
@@ -96,7 +97,7 @@ def push(self):
         event = Event()
         event.schema = self.dst_schema
         event.table = self.dst_table
-        event.file = self.path
+        event.filename = self.path
         event.fieldnames = self.fieldnames
         self.next_writer_builder.get().insert(event)
 
diff --git a/src/writer/writer.py b/src/writer/writer.py
index 6fabd2f..6d5c681 100644
--- a/src/writer/writer.py
+++ b/src/writer/writer.py
@@ -40,8 +40,8 @@ def listify(self, obj_or_list):
             # event_or_events is an object
             return [obj_or_list]
 
-    def convert(self, event):
-        return self.converter_builder.get().convert(event) if self.converter_builder else event
+    def convert(self, data):
+        return self.converter_builder.get().convert(data) if self.converter_builder else data
 
     def insert(self, event_or_events=None):
         # event_or_events = [