diff --git a/appveyor.yml b/appveyor.yml
index 281be915..c67a8cfb 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -1,24 +1,40 @@
 build: off
 version: 1.0.{build}
-
 skip_branch_with_pr: true
 
 init:
+- ps: >-
+
+    git config --global core.sharedRepository true
+
+    git config --global core.longpaths true
+
+    git config --global core.autocrlf input
+
+    if ($env:APPVEYOR_PULL_REQUEST_NUMBER -and $env:APPVEYOR_BUILD_NUMBER -ne ((Invoke-RestMethod `
+            https://ci.appveyor.com/api/projects/$env:APPVEYOR_ACCOUNT_NAME/$env:APPVEYOR_PROJECT_SLUG/history?recordsNumber=50).builds | `
+            Where-Object pullRequestId -eq $env:APPVEYOR_PULL_REQUEST_NUMBER)[0].buildNumber) { `
+              Write-Host "There are newer queued builds for this pull request, skipping build."
+              Exit-AppveyorBuild
+            }
+
+    If (($env:SKIP_NOTAG -eq "true") -and ($env:APPVEYOR_REPO_TAG -ne "true")) {
+              Write-Host "Skipping build, not at a tag."
+              Exit-AppveyorBuild
+          }
 
-  - git config --global core.sharedRepository true
-  - git config --global core.longpaths true
-  - git config --global core.autocrlf input
 
 environment:
 
   PYPI_VENDOR_DIR: '.\tests\pypi\'
   GIT_ASK_YESNO: 'false'
+  APPVEYOR_SAVE_CACHE_ON_ERROR: 'true'
+  APPVEYOR_SKIP_FINALIZE_ON_EXIT: 'true'
   SHELL: 'windows'
   PYTHON_ARCH: '64'
   PYTHONIOENCODING: 'utf-8'
 
   matrix:
-
     - PYTHON: 'C:\Python27-x64'
       PYTHON_VERSION: '2.7.x'
       TEST_SUITE: 'not install'
@@ -39,19 +55,60 @@ environment:
       PYTEST_ADDOPTS: '--cache-clear'
       RUN_INTEGRATION_TESTS: 'True'
 
+    - PYTHON: 'C:\Python37-x64'
+      PYTHON_VERSION: '3.7.x'
+      TEST_SUITE: 'not install'
+
+    - PYTHON: 'C:\Python37-x64'
+      PYTHON_VERSION: '3.7.x'
+      TEST_SUITE: 'install'
+      PYTEST_ADDOPTS: '--cache-clear'
+      RUN_INTEGRATION_TESTS: 'True'
+
 install:
-  - 'set PATH=%PYTHON%;%PYTHON%\Scripts;%PATH%'
-  - '%PYTHON%\python.exe -m pip install --upgrade pip'
-  - '%PYTHON%\python.exe -m pip install -e .'
-  - '%PYTHON%\python.exe -m pipenv run pip install -e .'
-  - '%PYTHON%\python.exe -m pipenv install --dev'
-  - '%PYTHON%\python.exe -m pipenv --venv'
-  - '%PYTHON%\python.exe -m pipenv --py'
-  - '%PYTHON%\python.exe -m pipenv run python --version'
+- ps: >-
+  
+    $script_path = Join-Path -path $env:PYTHON -childpath Scripts
+  
+    $py_exe = Join-Path -path $env:PYTHON -childpath python.exe
+  
+    $pipenv_exe = Join-Path -path $script_path -childpath pipenv.exe
+  
+    $env:PATH = "$py_path;$script_path;$env:PATH"
+  
+    Invoke-Expression "$py_exe -m pip install --upgrade pip invoke"
+  
+    Invoke-Expression "$py_exe -m pip install -e ."
+  
+    Invoke-Expression "$pipenv_exe install --dev"
+  
+    Invoke-Expression "$pipenv_exe --venv"
+  
+    Invoke-Expression "$pipenv_exe --py"
 
 cache:
-  - '%LocalAppData%\pip\cache'
+- '%LocalAppData%\pip\cache'
+- '%LocalAppData%\pipenv\cache'
 
 test_script:
-  - 'if "%RUN_INTEGRATION_TESTS%" == "True" (rmdir /s /q %LocalAppData%\pip\cache)'
-  - '%PYTHON%\python.exe -m pipenv run pytest -v -n 4 -m "%TEST_SUITE%" tests'
+
+- ps: >-
+    $script_path = Join-Path -path $env:PYTHON -childpath Scripts
+
+    $py_exe = Join-Path -path $env:PYTHON -childpath python.exe
+
+    $pipenv_exe = Join-Path -path $script_path -childpath pipenv.exe
+
+    $env:PATH = "$py_path;$script_path;$env:PATH"
+
+    $invoke_path = Join-Path -path $script_path -childpath invoke.exe
+
+    Invoke-Expression "$pipenv_exe run pytest -v -n 4 --ignore=pipenv\patched --ignore=pipenv\vendor -m `"$env:TEST_SUITE`" tests"
+
+    If ($env:RUN_INTEGRATION_TESTS -and ($env:PYTHON_VERSION -eq "3.6.x")) {
+
+      Invoke-Expression "$py_exe -m pip install invoke parver"
+
+      Invoke-Expression "$invoke_path vendoring.update"
+
+    }
diff --git a/run-tests.sh b/run-tests.sh
index a7059322..ce62ea5a 100755
--- a/run-tests.sh
+++ b/run-tests.sh
@@ -19,6 +19,7 @@ if [[ ! -z "$TEST_SUITE" ]]; then
 fi
 
 export PATH="~/.local/bin:$PATH"
+pip uninstall -y pipenv
 echo "Installing Pipenv…"
 pip install -e "$(pwd)" --upgrade
 pipenv install --deploy --dev
@@ -50,5 +51,9 @@ echo "$ pipenv run time pytest -v -n auto tests -m \"$TEST_SUITE\""
 # Better to run them sequentially.
 PIPENV_PYTHON=2.7 pipenv run time pytest -v -n auto tests -m "$TEST_SUITE"
 PIPENV_PYTHON=3.6 pipenv run time pytest -v -n auto tests -m "$TEST_SUITE"
+
+# test revendoring
+pip3 install --upgrade invoke requests parver
+python3 -m invoke vendoring.update
 # Cleanup junk.
 rm -fr .venv
diff --git a/tests/integration/test_pipenv.py b/tests/integration/test_pipenv.py
index 1b9b66a5..4734cbd7 100644
--- a/tests/integration/test_pipenv.py
+++ b/tests/integration/test_pipenv.py
@@ -4,11 +4,12 @@ XXX: Try our best to reduce tests in this file.
 """
 
 import os
-from tempfile import gettempdir, mkdtemp
+from tempfile import mkdtemp
 
 import mock
 import pytest
 
+from pipenv.utils import temp_environ
 from pipenv.project import Project
 from pipenv.vendor import delegator
 from pipenv._compat import Path
@@ -94,14 +95,11 @@ def test_proper_names_unamanged_virtualenv(PipenvInstance, pypi):
 def test_directory_with_leading_dash(PipenvInstance):
     def mocked_mkdtemp(suffix, prefix, dir):
         if suffix == '-project':
-            temp_dir = Path(gettempdir()) / '-dir-with-leading-dash'
-            temp_dir.mkdir()
-            return str(temp_dir)
-        else:
-            return mkdtemp(suffix, prefix, dir)
+            prefix = '-dir-with-leading-dash'
+        return mkdtemp(suffix, prefix, dir)
 
     with mock.patch('pipenv._compat.mkdtemp', side_effect=mocked_mkdtemp):
-        with PipenvInstance(chdir=True) as p:
+        with temp_environ(), PipenvInstance(chdir=True) as p:
             # This environment variable is set in the context manager and will
             # cause pipenv to use virtualenv, not pew.
             del os.environ['PIPENV_VENV_IN_PROJECT']