diff --git a/.bumpversion.cfg b/.bumpversion.cfg
index 131cbdc3b..9a8f10f3f 100644
--- a/.bumpversion.cfg
+++ b/.bumpversion.cfg
@@ -1,5 +1,5 @@
 [bumpversion]
-current_version = 0.15.2
+current_version = 0.16.0
 commit = False
 tag = False
 tag_name = {new_version}
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 2fd2e6ad4..b195d05e3 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,8 +1,9 @@
 image: ${IMAGE}
 
 before_script:
-  - sudo yum -y install python34 python34-pip python34-libs python34-setuptools
-  - sudo python3 -m pip install --upgrade pip
+  - sudo yum -y install python36 python36-libs python36-setuptools
+  - sudo python3.6 -m ensurepip --upgrade
+  - test -f /usr/bin/pip3 || sudo ln -sf /usr/local/bin/pip3 /usr/bin/pip3
   - sudo pip3 install --upgrade -r requirements/docs.txt
   - sudo pip3 install -e .
 
diff --git a/.gitmodules b/.gitmodules
index 3c46a1ce1..da242f1fd 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -43,3 +43,6 @@
 [submodule "src/watchmaker/static/salt/formulas/amazon-inspector-formula"]
 	path = src/watchmaker/static/salt/formulas/amazon-inspector-formula
 	url = https://github.com/plus3it/amazon-inspector-formula.git
+[submodule "src/watchmaker/static/salt/content"]
+	path = src/watchmaker/static/salt/content
+	url = https://github.com/plus3it/watchmaker-salt-content.git
diff --git a/.travis.yml b/.travis.yml
index d2ba3d3ea..4743747d0 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -54,6 +54,9 @@ notifications:
     on_failure: always
 jobs:
   include:
+    - stage: test
+      python: 3.7
+      dist: xenial
     - stage: test
       python: 3.6
       env:
diff --git a/CHANGELOG.md b/CHANGELOG.md
index cd8f14c11..23e51b6d6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,19 @@
 ## Changelog
 
+### 0.16.0
+
+**Commit Delta**: [Change from 0.15.2 release](https://github.com/plus3it/watchmaker/compare/0.15.2...0.16.0)
+
+**Released**: 2019.05.10
+
+**Summary**:
+
+*   Adds salt content locally as a submodule to better support Watchmaker standalone packages
+*   dotnet4-formula
+    -   Updates formula to support the use of Python3 versions of Salt
+*   join-domain-formula
+    -   Adds additional enhancements and logic to better handle the domin-join process in Linux
+
 ### 0.15.2
 
 **Commit Delta**: [Change from 0.15.1 release](https://github.com/plus3it/watchmaker/compare/0.15.1...0.15.2)
diff --git a/appveyor.yml b/appveyor.yml
index 9381ce258..49b6d4a75 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -14,6 +14,41 @@ init:
 install:
   - git submodule update --init --recursive
 test_script:
+  # ----- python 3.7, x64
+  # python envs
+  - set PYTHON_HOME=C:\Python37-x64
+  - set PYTHON_VERSION=3.7
+  - set PYTHON_ARCH=64
+
+  # install
+  - '%PYTHON_HOME%\Scripts\pip install --upgrade tox setuptools virtualenv wheel'
+
+    # versions
+  - '%PYTHON_HOME%\Scripts\virtualenv --version'
+  - '%PYTHON_HOME%\Scripts\tox --version'
+  - '%PYTHON_HOME%\Scripts\pip --version'
+
+  # test
+  - set TOXENV=3.7-codecov
+  - '%WITH_ENV% %PYTHON_HOME%\Scripts\tox -v'
+
+  # ----- python 3.7, x32
+  # python envs
+  - set PYTHON_HOME=C:\Python37
+  - set PYTHON_ARCH=32
+
+  # install
+  - '%PYTHON_HOME%\Scripts\pip install --upgrade tox setuptools virtualenv wheel'
+
+    # versions
+  - '%PYTHON_HOME%\Scripts\virtualenv --version'
+  - '%PYTHON_HOME%\Scripts\tox --version'
+  - '%PYTHON_HOME%\Scripts\pip --version'
+
+  # test
+  - set TOXENV=3.7-codecov
+  - '%WITH_ENV% %PYTHON_HOME%\Scripts\tox -v'
+
   # ----- python 3.6, x64
   # python envs
   - set PYTHON_HOME=C:\Python36-x64
diff --git a/requirements/build.txt b/requirements/build.txt
index 887c465a9..ba4f57321 100644
--- a/requirements/build.txt
+++ b/requirements/build.txt
@@ -1 +1 @@
-gravitybee==0.1.26
+gravitybee==0.1.27
diff --git a/requirements/check.txt b/requirements/check.txt
index 9b4d85afb..87c087aa4 100644
--- a/requirements/check.txt
+++ b/requirements/check.txt
@@ -1,4 +1,4 @@
-check-manifest==0.37
+check-manifest==0.38
 flake8==3.7.7
 flake8-bugbear==19.3.0
 flake8-builtins==1.4.1
@@ -6,10 +6,10 @@ flake8-docstrings==1.3.0
 flake8-isort==2.7.0
 flake8-future-import==0.4.5
 flake8-print==3.1.0
-isort==4.3.17
+isort==4.3.18
 m2r==0.2.1
 pep8-naming==0.8.2
 pydocstyle==3.0.0
-pygments==2.3.1
+pygments==2.4.0
 pylint==2.3.1
 readme-renderer==24.0
diff --git a/requirements/deploy.txt b/requirements/deploy.txt
index d0e244531..541c38ec9 100644
--- a/requirements/deploy.txt
+++ b/requirements/deploy.txt
@@ -1 +1 @@
-satsuki==0.1.13
+satsuki==0.1.15
diff --git a/requirements/docs.txt b/requirements/docs.txt
index c784a0da5..150676973 100644
--- a/requirements/docs.txt
+++ b/requirements/docs.txt
@@ -1,4 +1,4 @@
 m2r==0.2.1
-setuptools==41.0.0
+setuptools==41.0.1
 sphinx==2.0.1
 sphinx-rtd-theme==0.4.3
diff --git a/requirements/pip.txt b/requirements/pip.txt
index b79fbf1bd..b9b0f5d95 100644
--- a/requirements/pip.txt
+++ b/requirements/pip.txt
@@ -1 +1 @@
-pip==19.0.3
+pip==19.1.1
diff --git a/requirements/test.txt b/requirements/test.txt
index 0fe3af8a0..dfa17d73c 100644
--- a/requirements/test.txt
+++ b/requirements/test.txt
@@ -1,10 +1,11 @@
-mock==2.0.0
+mock==2.0.0;python_version=="2.6"  # pyup: ==2.0.0
+mock==3.0.5;python_version>="2.7"
 pytest==3.2.5;python_version=="2.6" or python_version=="3.3"  # pyup: ==3.2.5
-pytest==4.4.0;python_version=="2.7" or python_version>="3.4"
+pytest==4.4.2;python_version=="2.7" or python_version>="3.4"
 pytest-travis-fold==1.3.0
 pytest-catchlog==1.2.2;python_version=="2.6"
 pytest-cov==2.5.1;python_version=="2.6"  # pyup: ==2.5.1
-pytest-cov==2.6.1;python_version>="2.7"
+pytest-cov==2.7.1;python_version>="2.7"
 pytest-mock==1.6.3;python_version=="2.6"  # pyup: ==1.6.3
-pytest-mock==1.10.3;python_version>="2.7"
+pytest-mock==1.10.4;python_version>="2.7"
 wheel==0.29.0;python_version<="2.6"  # pyup: ==0.29.0
diff --git a/setup.cfg b/setup.cfg
index b05bf8616..9a9766963 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -3,7 +3,7 @@
 [metadata]
 name = watchmaker
 description = Applied Configuration Management
-version = 0.15.2
+version = 0.16.0
 author = Plus3IT Maintainers of Watchmaker
 author_email = projects@plus3it.com
 url = https://github.com/plus3it/watchmaker
@@ -31,7 +31,8 @@ classifiers =
 
 [options]
 install_requires =
-    backoff
+    backoff;python_version>="2.7"
+    backoff<1.7;python_version<"2.7"
     click;python_version>="2.7"
     click<7;python_version<"2.7"
     defusedxml;platform_system=="Windows"
@@ -39,7 +40,7 @@ install_requires =
     six
     pypiwin32;platform_system=="Windows"
     PyYAML;python_version>="2.7"
-    PyYAML<4;python_version<"2.7"    
+    PyYAML<4;python_version<"2.7"
     wheel<=0.29.0;python_version<"2.7"
 packages = find:
 include_package_data = True
diff --git a/src/watchmaker/static/config.yaml b/src/watchmaker/static/config.yaml
index 02e09a4b3..0df10e13e 100644
--- a/src/watchmaker/static/config.yaml
+++ b/src/watchmaker/static/config.yaml
@@ -5,7 +5,7 @@ all:
       computer_name: None
       environment: None
       ou_path: None
-      salt_content: https://s3.amazonaws.com/watchmaker/salt-content.zip
+      salt_content: None
       salt_states: Highstate
       user_formulas:
         # To add extra formulas, specify them as a map of
diff --git a/src/watchmaker/static/salt/content b/src/watchmaker/static/salt/content
new file mode 160000
index 000000000..e70b56cd0
--- /dev/null
+++ b/src/watchmaker/static/salt/content
@@ -0,0 +1 @@
+Subproject commit e70b56cd0600ad74f12ef75fe64e8188c2b9d848
diff --git a/src/watchmaker/static/salt/formulas/dotnet4-formula b/src/watchmaker/static/salt/formulas/dotnet4-formula
index 5c47fb02e..00b01d24a 160000
--- a/src/watchmaker/static/salt/formulas/dotnet4-formula
+++ b/src/watchmaker/static/salt/formulas/dotnet4-formula
@@ -1 +1 @@
-Subproject commit 5c47fb02eff2e0f0efffcb35d62b43b05343c850
+Subproject commit 00b01d24ad0ea2d649c580953090f99237e66588
diff --git a/src/watchmaker/static/salt/formulas/join-domain-formula b/src/watchmaker/static/salt/formulas/join-domain-formula
index 1fab4840f..a9acd1233 160000
--- a/src/watchmaker/static/salt/formulas/join-domain-formula
+++ b/src/watchmaker/static/salt/formulas/join-domain-formula
@@ -1 +1 @@
-Subproject commit 1fab4840f9ea75786283666f9c11402c21e22fe3
+Subproject commit a9acd1233a96f1904bffb67d504191a7c1252a05
diff --git a/src/watchmaker/utils/__init__.py b/src/watchmaker/utils/__init__.py
index c0e2cfdc5..e072b9409 100644
--- a/src/watchmaker/utils/__init__.py
+++ b/src/watchmaker/utils/__init__.py
@@ -4,6 +4,7 @@
                         unicode_literals, with_statement)
 
 import os
+import shutil
 import ssl
 
 import backoff
@@ -58,3 +59,26 @@ def urlopen_retry(uri):
         pass
 
     return urllib.request.urlopen(uri, **kwargs)
+
+
+def copytree(src, dst, force=False, **kwargs):
+    r"""
+    Copy OS directory trees from source to destination.
+
+    Args:
+        src: (:obj:`str`)
+            Source directory tree to be copied.
+            (*Default*: None)
+
+        dst: (:obj:`str`)
+            Destination where directory tree is to be copied.
+            (*Default*: None)
+
+        force: (:obj:`bool`)
+            Whether to delete destination prior to copy.
+            (*Default*: ``False``)
+    """
+    if force and os.path.exists(dst):
+        shutil.rmtree(dst)
+
+    shutil.copytree(src, dst, **kwargs)
diff --git a/src/watchmaker/workers/salt.py b/src/watchmaker/workers/salt.py
index 5dd83a6da..a80fbdb1d 100644
--- a/src/watchmaker/workers/salt.py
+++ b/src/watchmaker/workers/salt.py
@@ -169,7 +169,6 @@ def _prepare_for_install(self):
         ]
 
         for salt_dir in [
-            self.salt_base_env,
             self.salt_formula_root,
             self.salt_conf_path
         ]:
@@ -177,7 +176,7 @@ def _prepare_for_install(self):
                 os.makedirs(salt_dir)
             except OSError:
                 if not os.path.isdir(salt_dir):
-                    msg = ('Unable create directory - {0}'.format(salt_dir))
+                    msg = ('Unable to create directory - {0}'.format(salt_dir))
                     self.log.error(msg)
                     raise SystemError(msg)
 
@@ -194,11 +193,11 @@ def _get_formulas_conf(self):
         formulas_path = os.sep.join((static.__path__[0], 'salt', 'formulas'))
         for formula in os.listdir(formulas_path):
             formula_path = os.path.join(self.salt_formula_root, '', formula)
-            if os.path.exists(formula_path):
-                shutil.rmtree(formula_path)
-            shutil.copytree(
+            watchmaker.utils.copytree(
                 os.sep.join((formulas_path, formula)),
-                formula_path)
+                formula_path,
+                force=True
+            )
 
         # Obtain & extract any Salt formulas specified in user_formulas.
         for formula_name, formula_url in self.user_formulas.items():
@@ -241,7 +240,7 @@ def _get_formulas_conf(self):
         ]
 
     def _build_salt_formula(self, extract_dir):
-        if self.salt_content:
+        if self.salt_content and self.salt_content != 'None':
             salt_content_filename = watchmaker.utils.basename_from_uri(
                 self.salt_content
             )
@@ -255,6 +254,23 @@ def _build_salt_formula(self, extract_dir):
                 to_directory=extract_dir
             )
 
+        bundled_content = os.sep.join(
+            (static.__path__[0], 'salt', 'content')
+        )
+        for subdir in next(os.walk(bundled_content))[1]:
+            if (
+                not subdir.startswith('.') and
+                not os.path.exists(os.sep.join((extract_dir, subdir)))
+            ):
+                watchmaker.utils.copytree(
+                    os.sep.join((bundled_content, subdir)),
+                    os.sep.join((extract_dir, subdir))
+                )
+                self.log.info(
+                    'Using bundled content from %s',
+                    os.sep.join((bundled_content, subdir))
+                )
+
         with codecs.open(
             os.path.join(self.salt_conf_path, 'minion'),
             'r+',
diff --git a/tests/test_saltworker.py b/tests/test_saltworker.py
index ce023ce46..20164d662 100644
--- a/tests/test_saltworker.py
+++ b/tests/test_saltworker.py
@@ -1,12 +1,20 @@
 # -*- coding: utf-8 -*-
+# pylint: disable=redefined-outer-name,protected-access
 """Salt worker main test module."""
 from __future__ import (absolute_import, division, print_function,
                         unicode_literals, with_statement)
 
+import os
+
 import pytest
 
 from watchmaker.exceptions import InvalidValue
-from watchmaker.workers.salt import SaltBase
+from watchmaker.workers.salt import SaltBase, SaltWindows
+
+try:
+    from unittest.mock import MagicMock, patch
+except ImportError:
+    from mock import MagicMock, patch
 
 
 @pytest.fixture
@@ -53,3 +61,203 @@ def test_valid_environment(saltworker_client):
     saltworker_client.ent_env = 'dev'
     saltworker_client.valid_envs = [None, 'dev', 'test', 'prod']
     assert saltworker_client.before_install() is None
+
+
+@patch.dict(os.environ, {'systemdrive': 'C:'})
+def test_windows_missing_prepdir():
+    """Ensure that error raised when missing prep directory."""
+    system_params = {}
+    salt_config = {}
+
+    system_params['logdir'] = "logdir"
+    system_params['workingdir'] = "workingdir"
+
+    with pytest.raises(KeyError, match='prepdir'):
+        SaltWindows(system_params, **salt_config)
+
+
+@patch.dict(os.environ, {'systemdrive': 'C:'})
+def test_windows_missing_logdir():
+    """Ensure that error raised when missing log directory."""
+    system_params = {}
+    salt_config = {}
+
+    system_params['prepdir'] = "prepdir"
+    system_params['workingdir'] = "workingdir"
+
+    with pytest.raises(KeyError, match='logdir'):
+        SaltWindows(system_params, **salt_config)
+
+
+@patch.dict(os.environ, {'systemdrive': 'C:'})
+def test_windows_missing_workingdir():
+    """Ensure that error raised when missing working directory."""
+    system_params = {}
+    salt_config = {}
+
+    system_params['logdir'] = "logdir"
+    system_params['prepdir'] = "prepdir"
+
+    with pytest.raises(KeyError, match='workingdir'):
+        SaltWindows(system_params, **salt_config)
+
+
+@patch.dict(os.environ, {'systemdrive': 'C:'})
+def test_windows_defaults():
+    """Ensure that default values are populated as expected."""
+    system_params = {}
+    salt_config = {}
+
+    system_params['prepdir'] = "8cbda638-6b60-5628-870b-40fdf8add9f8"
+    system_params['logdir'] = "21fa57e2-9302-5934-978d-4ae40d5a2a55"
+    system_params['workingdir'] = "c990ee27-ff12-5d7e-9957-1d27d114c0ff"
+
+    salt_config['installer_url'] = "5de41ea1-902c-5e7c-ae86-89587057c6b3"
+    salt_config['ash_role'] = "b116b3e1-ee3f-5a83-9dd1-3d01d0d5e343"
+
+    win_salt = SaltWindows(system_params, **salt_config)
+
+    # assertions ===================
+    assert win_salt.installer_url == salt_config['installer_url']
+    assert win_salt.ash_role == salt_config['ash_role']
+    assert win_salt.salt_root == os.sep.join(("C:", 'Salt'))
+    assert win_salt.salt_call == os.sep.join(("C:", 'Salt', 'salt-call.bat'))
+    assert win_salt.salt_wam_root == os.sep.join((
+        system_params['prepdir'],
+        'Salt',
+    ))
+    assert win_salt.salt_conf_path == os.sep.join((
+        system_params['prepdir'],
+        'Salt',
+        'conf',
+    ))
+    assert win_salt.salt_srv == os.sep.join((
+        system_params['prepdir'],
+        'Salt',
+        'srv',
+    ))
+    assert win_salt.salt_win_repo == os.sep.join((
+        system_params['prepdir'],
+        'Salt',
+        'srv',
+        'winrepo',
+    ))
+    assert win_salt.salt_log_dir == system_params['logdir']
+    assert win_salt.salt_working_dir == system_params['workingdir']
+    assert win_salt.salt_working_dir_prefix == 'Salt-'
+
+    assert win_salt.salt_base_env == os.sep.join((
+        win_salt.salt_srv,
+        'states'
+    ))
+    assert win_salt.salt_formula_root == os.sep.join((
+        win_salt.salt_srv,
+        'formulas'
+    ))
+    assert win_salt.salt_pillar_root == os.sep.join((
+        win_salt.salt_srv,
+        'pillar'
+    ))
+    assert win_salt.salt_conf['file_client'] == 'local'
+    assert win_salt.salt_conf['hash_type'] == 'sha512'
+    assert win_salt.salt_conf['pillar_roots'] == {'base': [str(os.sep.join((
+        win_salt.salt_srv,
+        'pillar'
+    )))]}
+    assert win_salt.salt_conf['pillar_merge_lists']
+    assert win_salt.salt_conf['conf_dir'] == os.sep.join((
+        system_params['prepdir'],
+        'Salt',
+        'conf',
+    ))
+    assert win_salt.salt_conf['winrepo_source_dir'] == 'salt://winrepo'
+    assert win_salt.salt_conf['winrepo_dir'] == os.sep.join((
+        system_params['prepdir'],
+        'Salt',
+        'srv',
+        'winrepo',
+        'winrepo',
+    ))
+
+
+@patch.dict(os.environ, {'systemdrive': 'C:'})
+def test_windows_install():
+    """Ensure that install runs as expected."""
+    system_params = {}
+    salt_config = {}
+    system_params['prepdir'] = "0dcd877d-56cb-50c2-954a-80d1084b2216"
+    system_params['logdir'] = "647c2a49-baf9-511b-a17a-d6ebf0edd91c"
+    system_params['workingdir'] = "3d6ab2ef-09ad-59f1-a365-ee5f22c95c79"
+
+    salt_config['installer_url'] = "20c913cf-d825-533e-8649-4ab2fed5d9c1"
+    salt_config['ash_role'] = "f1d27775-9a3d-5e87-ab42-a79ac329ae4b"
+
+    saltworker_win = SaltWindows(system_params, **salt_config)
+
+    saltworker_win._prepare_for_install = MagicMock(return_value=None)
+    saltworker_win._install_package = MagicMock(return_value=None)
+    saltworker_win.service_stop = MagicMock(return_value=None)
+    saltworker_win._build_salt_formula = MagicMock(return_value=None)
+    saltworker_win.service_disable = MagicMock(return_value=True)
+    saltworker_win._set_grain = MagicMock(return_value=None)
+    saltworker_win.process_grains = MagicMock(return_value=None)
+    saltworker_win.run_salt = MagicMock(return_value=None)
+    saltworker_win.working_dir = system_params['workingdir']
+    saltworker_win.cleanup = MagicMock(return_value=None)
+
+    saltworker_win.install()
+
+    # assertions ===================
+    assert saltworker_win._prepare_for_install.call_count == 1
+    assert saltworker_win._install_package.call_count == 1
+    saltworker_win.service_stop.assert_called_with('salt-minion')
+    saltworker_win._build_salt_formula.assert_called_with(
+        saltworker_win.salt_srv
+    )
+    saltworker_win.service_disable.assert_called_with('salt-minion')
+    saltworker_win._set_grain.assert_called_with(
+        'ash-windows', {'lookup': {'role': salt_config['ash_role']}}
+    )
+    assert saltworker_win.process_grains.call_count == 1
+    saltworker_win.run_salt.assert_called_with('pkg.refresh_db')
+    assert saltworker_win.cleanup.call_count == 1
+
+
+@patch.dict(os.environ, {'systemdrive': 'C:'})
+@patch('codecs.open', autospec=True)
+@patch('os.makedirs', autospec=True)
+@patch('yaml.safe_dump', autospec=True)
+def test_windows_prep_install(mock_safe, mock_makedirs, mock_codec):
+    """Ensure that prep portion of install runs as expected."""
+    system_params = {}
+    salt_config = {}
+    system_params['prepdir'] = "ac2bf0c3-7985-569f-bfbd-3a8d8a13ce7d"
+    system_params['logdir'] = "5b0976f8-fcbc-50af-9459-8060589e70d9"
+    system_params['workingdir'] = "860f630a-f85d-5ed2-bd7a-bbdb48a53b2b"
+
+    salt_config['installer_url'] = "5f0c8635-4a10-5802-8145-732052a0b44b"
+    salt_config['ash_role'] = "fddc3dc3-3684-5924-bf55-bb1dbc4e4c08"
+
+    saltworker_win = SaltWindows(system_params, **salt_config)
+
+    saltworker_win.create_working_dir = MagicMock(
+        return_value=system_params['workingdir']
+    )
+    saltworker_win._prepare_for_install()
+
+    # assertions ===================
+    saltworker_win.create_working_dir.assert_called_with(
+        system_params['workingdir'],
+        'Salt-'
+    )
+    mock_makedirs.assert_called_with(saltworker_win.salt_conf_path)
+    mock_codec.assert_called_with(
+        os.path.join(saltworker_win.salt_conf_path, 'minion'),
+        'w',
+        encoding="utf-8"
+    )
+    mock_safe.assert_called_with(
+        saltworker_win.salt_conf,
+        mock_codec.return_value.__enter__(),
+        default_flow_style=False
+    )
diff --git a/tests/test_utils.py b/tests/test_utils.py
new file mode 100644
index 000000000..d6aa1bba7
--- /dev/null
+++ b/tests/test_utils.py
@@ -0,0 +1,45 @@
+# -*- coding: utf-8 -*-
+# pylint: disable=redefined-outer-name,protected-access
+"""Salt worker main test module."""
+from __future__ import (absolute_import, division, print_function,
+                        unicode_literals, with_statement)
+
+import watchmaker.utils
+
+try:
+    from unittest.mock import patch
+except ImportError:
+    from mock import patch
+
+
+@patch('os.path.exists', autospec=True)
+@patch('shutil.rmtree', autospec=True)
+@patch('shutil.copytree', autospec=True)
+def test_copytree_no_force(mock_copy, mock_rm, mock_exists):
+    """Test that copytree results in correct calls without force option."""
+    random_src = 'aba51e65-afd2-5020-8117-195f75e64258'
+    random_dst = 'f74d03de-7c1d-596f-83f3-73748f2e238f'
+
+    watchmaker.utils.copytree(random_src, random_dst)
+    mock_copy.assert_called_with(random_src, random_dst)
+    assert mock_rm.call_count == 0
+    assert mock_exists.call_count == 0
+
+    watchmaker.utils.copytree(random_src, random_dst, force=False)
+    mock_copy.assert_called_with(random_src, random_dst)
+    assert mock_rm.call_count == 0
+    assert mock_exists.call_count == 0
+
+
+@patch('os.path.exists', autospec=True)
+@patch('shutil.rmtree', autospec=True)
+@patch('shutil.copytree', autospec=True)
+def test_copytree_force(mock_copy, mock_rm, mock_exists):
+    """Test that copytree results in correct calls with force option."""
+    random_src = '44b6df59-db6f-57cb-a570-ccd55d782561'
+    random_dst = '72fe7962-a7af-5f2f-899b-54798bc5e79f'
+
+    watchmaker.utils.copytree(random_src, random_dst, force=True)
+    mock_copy.assert_called_with(random_src, random_dst)
+    mock_rm.assert_called_with(random_dst)
+    mock_exists.assert_called_with(random_dst)
diff --git a/tox.ini b/tox.ini
index 34f113197..2cb67c89f 100644
--- a/tox.ini
+++ b/tox.ini
@@ -3,7 +3,7 @@
 [tox]
 envlist =
     check,
-    {2.6,2.7,3.4,3.5,3.6,pypy}-codecov,
+    {2.6,2.7,3.4,3.5,3.6,3.7,pypy}-codecov,
     report,
     docs