diff --git a/gixy/core/builtin_variables.py b/gixy/core/builtin_variables.py
index 5fbdd13..c73738e 100644
--- a/gixy/core/builtin_variables.py
+++ b/gixy/core/builtin_variables.py
@@ -3,19 +3,19 @@ from gixy.core.variable import Variable
 
 BUILTIN_VARIABLES = {
     # http://nginx.org/en/docs/http/ngx_http_core_module.html#var_uri
-    'uri': '/[^\x20\t]*',
+    'uri': r'/[^\x20\t]*',
     # http://nginx.org/en/docs/http/ngx_http_core_module.html#var_document_uri
-    'document_uri': '/[^\x20\t]*',
+    'document_uri': r'/[^\x20\t]*',
     # http://nginx.org/en/docs/http/ngx_http_core_module.html#var_arg_
-    'arg_': '[^\s&]+',
+    'arg_': r'[^\s&]+',
     # http://nginx.org/en/docs/http/ngx_http_core_module.html#var_args
-    'args': '[^\s]+',
+    'args': r'[^\s]+',
     # http://nginx.org/en/docs/http/ngx_http_core_module.html#var_query_string
-    'query_string': '[^\s]+',
+    'query_string': r'[^\s]+',
     # http://nginx.org/en/docs/http/ngx_http_core_module.html#var_request_uri
-    'request_uri': '/[^\s]*',
+    'request_uri': r'/[^\s]*',
     # http://nginx.org/en/docs/http/ngx_http_core_module.html#var_http_
-    'http_': '[\x21-\x7e]',
+    'http_': r'[\x21-\x7e]',
 
     # http://nginx.org/en/docs/http/ngx_http_upstream_module.html#var_upstream_http_
     'upstream_http_': '',
diff --git a/gixy/directives/directive.py b/gixy/directives/directive.py
index 04ee93b..be9b29f 100644
--- a/gixy/directives/directive.py
+++ b/gixy/directives/directive.py
@@ -115,7 +115,7 @@ class SetByLuaDirective(Directive):
 class RewriteDirective(Directive):
     nginx_name = 'rewrite'
     provide_variables = True
-    boundary = Regexp('[^\s\r\n]')
+    boundary = Regexp(r'[^\s\r\n]')
 
     def __init__(self, name, args):
         super(RewriteDirective, self).__init__(name, args)
diff --git a/gixy/plugins/http_splitting.py b/gixy/plugins/http_splitting.py
index 62a104a..134148b 100644
--- a/gixy/plugins/http_splitting.py
+++ b/gixy/plugins/http_splitting.py
@@ -4,7 +4,7 @@ from gixy.core.variable import compile_script
 
 
 class http_splitting(Plugin):
-    """
+    r"""
     Insecure examples:
         rewrite ^ http://$host$uri;
         return 301 http://$host$uri;
diff --git a/gixy/plugins/origins.py b/gixy/plugins/origins.py
index 78f5999..977d0d7 100644
--- a/gixy/plugins/origins.py
+++ b/gixy/plugins/origins.py
@@ -8,7 +8,7 @@ LOG = logging.getLogger(__name__)
 
 
 class origins(Plugin):
-    """
+    r"""
     Insecure example:
         if ($http_referer !~ "^https?://([^/]+metrika.*yandex\.ru/"){
             add_header X-Frame-Options SAMEORIGIN;
@@ -29,7 +29,7 @@ class origins(Plugin):
         if self.config.get('domains') and self.config.get('domains')[0] and self.config.get('domains')[0] != '*':
             domains = '|'.join(re.escape(d) for d in self.config.get('domains'))
         else:
-            domains = '[^/.]*\.[^/]{2,7}'
+            domains = r'[^/.]*\.[^/]{2,7}'
 
         scheme = 'https{http}'.format(http=('?' if not self.config.get('https_only') else ''))
         regex = r'^{scheme}://(?:[^/.]*\.){{0,10}}(?P<domain>{domains})(?::\d*)?(?:/|\?|$)'.format(