diff --git a/mbget/config.py b/mbget/config.py
index 6a7e8ef..cdde665 100644
--- a/mbget/config.py
+++ b/mbget/config.py
@@ -36,8 +36,11 @@ class Config(object):
     def __init__(self, args):
         if args.token is not None:
             self.__token = args.token[0]
+        elif "MBGET_GH_TOKEN" in os.environ:
+            self.__token = os.environ["MBGET_GH_TOKEN"]
         else:
             self.__token = None
+
         self.__package = args.package
         self.__output_dir = args.directory
         self.__jungle = args.jungle

diff --git a/tests/test_config.py b/tests/test_config.py
new file mode 100644
index 0000000..28fbdb3
--- /dev/null
+++ b/tests/test_config.py
@@ -0,0 +1,126 @@
+# -*- coding: utf-8 -*-
+
+# ########################## Copyrights and license ########################## #
+#                                                                              #
+# Copyright 2020 Greg Caufield <greg@embeddedcoffee.ca>                        #
+#                                                                              #
+# This file is part of MonkeyPack Pacage Manager                               #
+#                                                                              #
+# The MIT Licence                                                              #
+#                                                                              #
+# Permission is hereby granted, free of charge, to any person obtaining a copy #
+# of this software and associated documentation files (the "Software"), to     #
+# deal in the Software without restriction, including without limitation the   #
+# rights to use, copy, modify, merge, publish, distribute, sublicense, and/or  #
+# sell copies of the Software, and to permit persons to whom the Software is   #
+# furnished to do so, subject to the following conditions:                     #
+#                                                                              #
+# The above copyright notice and this permission notice shall be included in   #
+# all copies or substantial portions of the Software.                          #
+#                                                                              #
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR   #
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,     #
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE  #
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER       #
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING      #
+# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS #
+# IN THE SOFTWARE.                                                             #
+#                                                                              #
+# ############################################################################ #
+
+import unittest
+from unittest.mock import patch, mock_open, Mock
+
+from mbget.config import Config
+
+
+class MicroMock(object):
+    def __init__(self, **kwargs):
+        self.__dict__.update(kwargs)
+
+
+class TestConfig(unittest.TestCase):
+    @staticmethod
+    def __build_args(
+        token=None, package="packages.txt", directory="barrels", jungle="barrels.jungle"
+    ):
+        return MicroMock(
+            token=token, package=package, directory=directory, jungle=jungle
+        )
+
+    def test_can_init_config(self):
+        Config(self.__build_args())
+
+    def test_token_is_none(self):
+        cfg = Config(self.__build_args(token=None))
+        self.assertIsNone(cfg.token)
+
+    def test_token_is_valid(self):
+        cfg = Config(self.__build_args(token=["12345abc"]))
+        self.assertEqual("12345abc", cfg.token)
+
+    def test_token_from_env_if_arg_is_none(self):
+        with patch.dict("os.environ", {"MBGET_GH_TOKEN": "125aeb"}):
+            cfg = Config(self.__build_args(token=None))
+            self.assertEqual("125aeb", cfg.token)
+
+    def test_token_prioritizes_args_over_env(self):
+        with patch.dict("os.environ", {"MBGET_GH_TOKEN": "125aeb"}):
+            cfg = Config(self.__build_args(token=["12345abc"]))
+            self.assertEqual("12345abc", cfg.token)
+
+    def test_barrel_dir_is_valid(self):
+        cfg = Config(self.__build_args(directory="barrels"))
+        self.assertEqual("barrels", cfg.barrel_dir)
+
+    def test_package_is_valid(self):
+        cfg = Config(self.__build_args(package="packages.txt"))
+        self.assertEqual("packages.txt", cfg.package)
+
+    def test_jungle_is_valid(self):
+        cfg = Config(self.__build_args(jungle="barrels.jungle"))
+        self.assertEqual("barrels.jungle", cfg.jungle)
+
+    def test_prepare_builds_output_dir_if_not_exists(self):
+        cfg = Config(self.__build_args(directory="barrels"))
+
+        with patch("os.path.exists") as e, patch("os.mkdir") as m:
+            e.return_value = False
+            cfg.prepare_project_dir()
+            m.assert_called_once_with("barrels")
+
+    def test_prepare_does_not_build_output_dir_if_exists(self):
+        cfg = Config(self.__build_args(directory="barrels"))
+
+        with patch("os.path.exists") as e, patch("os.mkdir") as m:
+            e.return_value = True
+            cfg.prepare_project_dir()
+            m.assert_not_called()
+
+    def test_open_file_calls_callback_with_expected_stream(self):
+        cfg = Config(self.__build_args())
+        cb = Mock()
+
+        with patch("builtins.open", mock_open(read_data="A Test file")):
+            cfg.open_file("mockfile", "r", cb)
+
+        cb.assert_called_once()
+
+    def test_open_file_passes_file_to_callback(self):
+        cfg = Config(self.__build_args())
+
+        with patch("builtins.open", mock_open(read_data="A Test file")):
+            cfg.open_file(
+                "mockfile", "r", lambda f: self.assertEqual("A Test file", f.readline())
+            )
+
+    def test_open_file_can_write(self):
+        cfg = Config(self.__build_args())
+        m = mock_open()
+
+        with patch("builtins.open", m):
+            cfg.open_file("mockfile", "w", lambda f: f.write("some data"))
+
+        m.assert_called_once_with("mockfile", "w")
+        handle = m()
+        handle.write.assert_called_once_with("some data")

Pull GitHub token from environment
## Describe the feature
Add the option to pass the GitHub token using an environment variable.

tests/test_config.py::TestConfig::test_token_from_env_if_arg_is_none
tests/test_config.py::TestConfig::test_barrel_dir_is_valid tests/test_config.py::TestConfig::test_can_init_config tests/test_config.py::TestConfig::test_jungle_is_valid tests/test_config.py::TestConfig::test_open_file_calls_callback_with_expected_stream tests/test_config.py::TestConfig::test_open_file_can_write tests/test_config.py::TestConfig::test_open_file_passes_file_to_callback tests/test_config.py::TestConfig::test_package_is_valid tests/test_config.py::TestConfig::test_prepare_builds_output_dir_if_not_exists tests/test_config.py::TestConfig::test_prepare_does_not_build_output_dir_if_exists tests/test_config.py::TestConfig::test_token_is_none tests/test_config.py::TestConfig::test_token_is_valid tests/test_config.py::TestConfig::test_token_prioritizes_args_over_env