diff --git a/docker/Gemfile b/docker/Gemfile
index b4716815..d434a212 100644
--- a/docker/Gemfile
+++ b/docker/Gemfile
@@ -1,5 +1,5 @@
 source 'https://rubygems.org'
 
-gem 'rubocop'
-gem 'puppet-lint'
-gem 'foodcritic'
+gem 'rubocop', '~>0.49'
+gem 'puppet-lint', '~>2.2'
+gem 'foodcritic', '~>12.0'
diff --git a/docker/ruby2.Dockerfile b/docker/ruby2.Dockerfile
index 3aa63f04..01050406 100644
--- a/docker/ruby2.Dockerfile
+++ b/docker/ruby2.Dockerfile
@@ -1,4 +1,4 @@
-FROM ruby:2.5-alpine
+FROM ruby:2.4-alpine
 
 RUN mkdir /src \
   && mkdir /tool \
diff --git a/lintreview/tools/eslint.py b/lintreview/tools/eslint.py
index 063fc03c..3af6029e 100644
--- a/lintreview/tools/eslint.py
+++ b/lintreview/tools/eslint.py
@@ -2,6 +2,7 @@
 import logging
 import os
 import re
+from lintreview.config import comma_value
 from lintreview.review import IssueComment
 from lintreview.tools import Tool, process_checkstyle
 import lintreview.docker as docker
@@ -23,7 +24,8 @@ def match_file(self, filename):
         """
         base = os.path.basename(filename)
         name, ext = os.path.splitext(base)
-        return ext == '.js' or ext == '.jsx'
+        extensions = comma_value(self.options.get('extensions', '.js,.jsx'))
+        return ext in extensions
 
     def has_fixer(self):
         """Eslint has a fixer that can be enabled
diff --git a/settings.sample.py b/settings.sample.py
index db2de88a..dcc92558 100644
--- a/settings.sample.py
+++ b/settings.sample.py
@@ -14,9 +14,9 @@ def env(key, default=None, cast=str):
 # gunicorn config
 bind = env('LINTREVIEW_GUNICORN_BIND', '127.0.0.1:5000')
 errorlog = env('LINTREVIEW_GUNICORN_LOG_ERROR',
-                          'lintreview.error.log')
+               'lintreview.error.log')
 accesslog = env('LINTREVIEW_GUNICORN_LOG_ACCESS',
-                           'lintreview.access.log')
+                'lintreview.access.log')
 debug = env('LINTREVIEW_GUNICORN_DEBUG', True, bool)
 loglevel = env('LINTREVIEW_GUNICORN_LOGLEVEL', 'debug')
 
@@ -87,8 +87,9 @@ def env(key, default=None, cast=str):
 SUMMARY_THRESHOLD = env('LINTREVIEW_SUMMARY_THRESHOLD', 50, int)
 
 # Used as the author information when making commits
-GITHUB_AUTHOR_NAME = 'lintreview'
-GITHUB_AUTHOR_EMAIL = 'lintreview@example.com'
+GITHUB_AUTHOR_NAME = env('LINTREVIEW_GITHUB_AUTHOR_NAME', 'lintreview')
+GITHUB_AUTHOR_EMAIL = env('LINTREVIEW_GITHUB_AUTHOR_EMAIL',
+                          'lintreview@example.com')
 
 # Status Configuration
 ######################
diff --git a/tests/tools/test_eslint.py b/tests/tools/test_eslint.py
index d800b586..7e7c04cf 100644
--- a/tests/tools/test_eslint.py
+++ b/tests/tools/test_eslint.py
@@ -29,6 +29,16 @@ def test_match_file(self):
         self.assertTrue(self.tool.match_file('test.jsx'))
         self.assertTrue(self.tool.match_file('dir/name/test.js'))
 
+    def test_match_file__extensions(self):
+        options = {
+            'extensions': '.js,.jsm'
+        }
+        tool = Eslint(self.problems, options)
+        self.assertFalse(tool.match_file('test.php'))
+        self.assertFalse(tool.match_file('test.jsx'))
+        self.assertTrue(tool.match_file('test.js'))
+        self.assertTrue(tool.match_file('test.jsm'))
+
     @requires_image('nodejs')
     def test_check_dependencies(self):
         self.assertTrue(self.tool.check_dependencies())