diff --git a/docs/upgrade.rst b/docs/upgrade.rst
--- a/docs/upgrade.rst
+++ b/docs/upgrade.rst
@@ -39,8 +39,8 @@ Back up your configuration
 
 Make a copy of your Kallithea configuration (``.ini``) file.
 
-If you are using :ref:`rcextensions <customization>`, you should also
-make a copy of the entire ``rcextensions`` directory.
+If you are using custom :ref:`extensions <customization>`, you should also
+make a copy of the ``extensions.py`` file.
 
 Back up your database
 ^^^^^^^^^^^^^^^^^^^^^
diff --git a/docs/usage/customization.rst b/docs/usage/customization.rst
--- a/docs/usage/customization.rst
+++ b/docs/usage/customization.rst
@@ -39,13 +39,14 @@ running::
 .. _less: http://lesscss.org/
 
 
-Behavioral customization: rcextensions
---------------------------------------
+Behavioral customization: Kallithea extensions
+----------------------------------------------
 
-Some behavioral customization can be done in Python using ``rcextensions``, a
-custom Python package that can extend Kallithea functionality.
+Some behavioral customization can be done in Python using Kallithea
+``extensions``, a custom Python file you can create to extend Kallithea
+functionality.
 
-With ``rcextensions`` it's possible to add additional mappings for Whoosh
+With ``extensions`` it's possible to add additional mappings for Whoosh
 indexing and statistics, to add additional code into the push/pull/create/delete
 repository hooks (for example to send signals to build bots such as Jenkins) and
 even to monkey-patch certain parts of the Kallithea source code (for example
@@ -55,9 +56,14 @@ To generate a skeleton extensions packag
 
     kallithea-cli extensions-create -c my.ini
 
-This will create an ``rcextensions`` package next to the specified ``ini`` file.
-See the ``__init__.py`` file inside the generated ``rcextensions`` package
-for more details.
+This will create an ``extensions.py`` file next to the specified ``ini`` file.
+You can find more details inside this file.
+
+For compatibility with previous releases of Kallithea, a directory named
+``rcextensions`` with a file ``__init__.py`` inside of it can also be used. If
+both an ``extensions.py`` file and an ``rcextensions`` directory are found, only
+``extensions.py`` will be loaded. Note that the name ``rcextensions`` is
+deprecated and support for it will be removed in a future release.
 
 
 Behavioral customization: code changes
diff --git a/kallithea/bin/kallithea_cli_extensions.py b/kallithea/bin/kallithea_cli_extensions.py
--- a/kallithea/bin/kallithea_cli_extensions.py
+++ b/kallithea/bin/kallithea_cli_extensions.py
@@ -33,15 +33,15 @@ from kallithea.lib.utils2 import ask_ok
 def extensions_create():
     """Write template file for extending Kallithea in Python.
 
-    An rcextensions directory with a __init__.py file will be created next to
-    the ini file. Local customizations in that file will survive upgrades.
-    The file contains instructions on how it can be customized.
+    Create a template `extensions.py` file next to the ini file. Local
+    customizations in that file will survive upgrades. The file contains
+    instructions on how it can be customized.
     """
     here = kallithea.CONFIG['here']
     content = pkg_resources.resource_string(
-        'kallithea', os.path.join('config', 'rcextensions', '__init__.py')
+        'kallithea', os.path.join('config', 'extensions', 'extensions.py')
     )
-    ext_file = os.path.join(here, 'rcextensions', '__init__.py')
+    ext_file = os.path.join(here, 'extensions.py')
     if os.path.exists(ext_file):
         msg = ('Extension file %s already exists, do you want '
                'to overwrite it ? [y/n] ') % ext_file
diff --git a/kallithea/config/rcextensions/__init__.py b/kallithea/config/extensions/extensions.py
rename from kallithea/config/rcextensions/__init__.py
rename to kallithea/config/extensions/extensions.py
diff --git a/kallithea/lib/pygmentsutils.py b/kallithea/lib/pygmentsutils.py
--- a/kallithea/lib/pygmentsutils.py
+++ b/kallithea/lib/pygmentsutils.py
@@ -69,7 +69,7 @@ def get_index_filenames():
 
 def get_custom_lexer(extension):
     """
-    returns a custom lexer if it's defined in rcextensions module, or None
+    returns a custom lexer if it's defined in the extensions module, or None
     if there's no custom lexer defined
     """
     import kallithea
diff --git a/kallithea/lib/utils.py b/kallithea/lib/utils.py
--- a/kallithea/lib/utils.py
+++ b/kallithea/lib/utils.py
@@ -522,11 +522,15 @@ def repo2db_mapper(initial_repo_dict, re
 
 def load_extensions(root_path):
     try:
-        ext = create_module('rc', os.path.join(root_path, 'rcextensions', '__init__.py'))
+        ext = create_module('extensions', os.path.join(root_path, 'extensions.py'))
     except FileNotFoundError:
-        return
+        try:
+            ext = create_module('rc', os.path.join(root_path, 'rcextensions', '__init__.py'))
+            log.warning('The name "rcextensions" is deprecated. Please use a file `extensions.py` instead of a directory `rcextensions`.')
+        except FileNotFoundError:
+            return
 
-    log.info('Loaded rcextensions from %s', ext)
+    log.info('Loaded Kallithea extensions from %s', ext)
     kallithea.EXTENSIONS = ext
 
     # Additional mappings that are not present in the pygments lexers