diff --git a/pipenv/core.py b/pipenv/core.py
index 4f1827b6..d301dca4 100644
--- a/pipenv/core.py
+++ b/pipenv/core.py
@@ -15,10 +15,10 @@ import click_completion
 import crayons
 import dotenv
 import delegator
-import pexpect
+from .vendor import pexpect
 import pipfile
 import pipdeptree
-from pipreqs import pipreqs
+from .vendor.pipreqs import pipreqs
 from blindspin import spinner
 
 from requests.packages import urllib3
@@ -183,7 +183,7 @@ def cleanup_virtualenv(bare=True):
 
 def import_requirements(r=None, dev=False):
     import pip9
-    from pip9.req.req_file import parse_requirements
+    from .vendor.pip9.req.req_file import parse_requirements
 
     # Parse requirements.txt file with Pip's parser.
     # Pip requires a `PipSession` which is a subclass of requests.Session.
@@ -2079,7 +2079,7 @@ def do_uninstall(
 
 
 def do_shell(three=None, python=False, fancy=False, shell_args=None):
-    from pipenv.patched.pew import pew
+    from .patched.pew import pew
 
     # Ensure that virtualenv is available.
     ensure_project(three=three, python=python, validate=False)
diff --git a/pipenv/project.py b/pipenv/project.py
index 0127261d..af663363 100644
--- a/pipenv/project.py
+++ b/pipenv/project.py
@@ -19,7 +19,7 @@ try:
 except ImportError:
     import pathlib2 as pathlib
 
-from pip9 import ConfigOptionParser
+from .vendor.pip9 import ConfigOptionParser
 from .cmdparse import Script
 from .utils import (
     mkdir_p,
@@ -218,7 +218,7 @@ class Project(object):
 
     @classmethod
     def _get_virtualenv_location(cls, name):
-        from pipenv.patched.pew.pew import get_workon_home
+        from .patched.pew.pew import get_workon_home
         venv = get_workon_home() / name
         if not venv.exists():
             return ''
@@ -262,7 +262,7 @@ class Project(object):
             return clean_name, encoded_hash
 
         # Check for different capitalization of the same project.
-        from pipenv.patched.pew.pew import lsenvs
+        from .patched.pew.pew import lsenvs
         for env in lsenvs():
             try:
                 env_name, hash_ = env.rsplit('-', 1)
diff --git a/pipenv/utils.py b/pipenv/utils.py
index 4a4ce008..790d1c7d 100644
--- a/pipenv/utils.py
+++ b/pipenv/utils.py
@@ -20,7 +20,7 @@ try:
     from weakref import finalize
 except ImportError:
     try:
-        from backports.weakref import finalize
+        from .vendor.backports.weakref import finalize
     except ImportError:
         class finalize(object):
             def __init__(self, *args, **kwargs):
@@ -40,20 +40,20 @@ try:
     from pathlib import Path
 except ImportError:
     try:
-        from pathlib2 import Path
+        from .vendor.pathlib2 import Path
     except ImportError:
         pass
 from distutils.spawn import find_executable
 from contextlib import contextmanager
-from pipenv.patched.piptools.resolver import Resolver
-from pipenv.patched.piptools.repositories.pypi import PyPIRepository
-from pipenv.patched.piptools.scripts.compile import get_pip_command
-from pipenv.patched.piptools import logging as piptools_logging
-from pipenv.patched.piptools.exceptions import NoCandidateFound
-from pip9.download import is_archive_file
-from pip9.exceptions import DistributionNotFound
-from pip9.index import Link
-from pip9._vendor.requests.exceptions import HTTPError, ConnectionError
+from .patched.piptools.resolver import Resolver
+from .patched.piptools.repositories.pypi import PyPIRepository
+from .patched.piptools.scripts.compile import get_pip_command
+from .patched.piptools import logging as piptools_logging
+from .patched.piptools.exceptions import NoCandidateFound
+from .vendor.pip9.download import is_archive_file
+from .vendor.pip9.exceptions import DistributionNotFound
+from .vendor.pip9.index import Link
+from .vendor.pip9._vendor.requests.exceptions import HTTPError, ConnectionError
 
 from .pep508checker import lookup
 from .environments import PIPENV_MAX_ROUNDS, PIPENV_CACHE_DIR
@@ -72,8 +72,8 @@ requests = requests.Session()
 
 
 def get_requirement(dep):
-    from pip9.req.req_install import _strip_extras, Wheel
-    import requirements
+    from .vendor.pip9.req.req_install import _strip_extras, Wheel
+    from .vendor import requirements
     """Pre-clean requirement strings passed to the requirements parser.
 
     Ensures that we can accept both local and relative paths, file and VCS URIs,
@@ -789,7 +789,7 @@ def is_editable(pipfile_entry):
 
 
 def is_vcs(pipfile_entry):
-    from pipenv.vendor import requirements
+    from .vendor import requirements
 
     """Determine if dictionary entry from Pipfile is for a vcs dependency."""
     if hasattr(pipfile_entry, 'keys'):
@@ -807,8 +807,8 @@ def is_vcs(pipfile_entry):
 
 def is_installable_file(path):
     """Determine if a path can potentially be installed"""
-    from pip9.utils import is_installable_dir
-    from pip9.utils.packaging import specifiers
+    from .vendor.pip9.utils import is_installable_dir
+    from .vendor.pip9.utils.packaging import specifiers
 
     if hasattr(path, 'keys') and any(
         key for key in path.keys() if key in ['file', 'path']
@@ -859,7 +859,7 @@ def is_file(package):
 
 def pep440_version(version):
     """Normalize version to PEP 440 standards"""
-    from pip9.index import parse_version
+    from .vendor.pip9.index import parse_version
 
     # Use pip built-in version parser.
     return str(parse_version(version))
diff --git a/run-tests.sh b/run-tests.sh
index 92dadae5..8e3eddde 100755
--- a/run-tests.sh
+++ b/run-tests.sh
@@ -7,6 +7,7 @@ set -eo pipefail
 # Set the PYPI vendor URL for pytest-pypi.
 PYPI_VENDOR_DIR="$(pwd)/tests/pypi/"
 export PYPI_VENDOR_DIR
+export PYTHONIOENCODING="utf-8"
 
 prefix() {
   sed "s/^/   $1:    /"
diff --git a/tests/__init__.py b/tests/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/tests/integration/__init__.py b/tests/integration/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/tests/unit/__init__.py b/tests/unit/__init__.py
new file mode 100644
index 00000000..e69de29b