diff --git a/main.py b/main.py
index b34fa8c..19461b4 100644
--- a/main.py
+++ b/main.py
@@ -33,6 +33,8 @@ import datetime
 import httplib2
 import os
 import requests
+import logging
+from logging.handlers import RotatingFileHandler
 
 from apiclient import discovery
 from oauth2client import client
@@ -41,6 +43,45 @@ from oauth2client.file import Storage
 
 import icalendar
 
+DEBUG = False
+APP_DIR = os.path.dirname(os.path.abspath(__file__))
+if DEBUG:
+    DATA_DIR = APP_DIR
+else:
+    home_dir = os.path.expanduser('~')
+    DATA_DIR = os.path.join(home_dir, ".ntnoe", "")
+    if not os.path.exists(DATA_DIR):
+        os.makedirs(DATA_DIR)
+
+##### Logger stuff #####
+
+logger = logging.getLogger()
+
+if DEBUG:
+    logger.setLevel(logging.DEBUG)
+else:
+    logger.setLevel(logging.INFO)
+
+formatter = logging.Formatter('%(asctime)s :: %(levelname)s :: %(message)s')
+
+file_handler = RotatingFileHandler(
+    os.path.join(DATA_DIR, 'log.txt'), 'a', 1000000, 1)
+if DEBUG:
+    file_handler.setLevel(logging.DEBUG)
+else:
+    file_handler.setLevel(logging.INFO)
+
+file_handler.setFormatter(formatter)
+logger.addHandler(file_handler)
+
+if DEBUG:
+    stream_handler = logging.StreamHandler()
+    stream_handler.setLevel(logging.DEBUG)
+    stream_handler.setFormatter(formatter)
+    logger.addHandler(stream_handler)
+
+########################
+
 
 TIMEDELTA_SYNCHRO = datetime.timedelta(days=15)  # Number of days to look for
 # for synchronization
@@ -112,8 +153,7 @@ def get_credentials():
     Returns:
         Credentials, the obtained credential.
     """
-    home_dir = os.path.expanduser('~')
-    credential_dir = os.path.join(home_dir, '.credentials')
+    credential_dir = os.path.join(DATA_DIR, 'credentials')
     if not os.path.exists(credential_dir):
         os.makedirs(credential_dir)
     credential_path = os.path.join(credential_dir, 'ntnoe.json')
@@ -123,7 +163,7 @@ def get_credentials():
     if not credentials or credentials.invalid:
         flow = client.flow_from_clientsecrets(CLIENT_SECRET_FILE, SCOPES)
         flow.user_agent = APPLICATION_NAME
-        print('Storing credentials to ' + credential_path)
+        logger.info('Storing credentials to ' + credential_path)
         credentials = tools.run_flow(flow, store)
 
     return credentials
@@ -158,7 +198,7 @@ def main():
             ntnoe_calendar_id = c['id']
 
     if not ntnoe_calendar_id:
-        print("Creating ntnoe calendar...")
+        logger.info("Creating ntnoe calendar...")
         created = service.calendars().insert(body={
             'defaultReminders' : [],
             'selected' : True,
@@ -175,7 +215,7 @@ def main():
     ).execute()
 
     for event in former_ones['items']:
-        print('Deleting event : {}'.format(event['id']))
+        logger.info('Deleting event : {}'.format(event['id']))
         service.events().delete(
             calendarId=ntnoe_calendar_id,
             eventId=event['id']
@@ -196,7 +236,7 @@ def main():
             calendarId=ntnoe_calendar_id,
             body=event.as_google()
         ).execute()
-        print("Adding event : {}".format(event['id']))
+        logger.info("Adding event : {}".format(event['id']))
 
 
 if __name__ == '__main__':