diff --git a/Jenkinsfile b/Jenkinsfile
index c6b9a8c..16dddc6 100644
--- a/Jenkinsfile
+++ b/Jenkinsfile
@@ -3,10 +3,18 @@
 pipeline {
     agent any
     options { disableConcurrentBuilds() }
+    environment {
+        TMPDIR = "/tmp/$BUILD_TAG"
+    }
     stages {
         stage('Unit Tests') {
             steps {
-                sh 'tox -rv'
+                sh "mkdir ${env.TMPDIR}"
+                sh """
+virtualenv -p python3 ${env.TMPDIR}/venv/
+. ${env.TMPDIR}/venv/bin/activate
+${env.TMPDIR}/venv/bin/pip install tox
+PGPORT=`python -c 'import struct; import socket; s=socket.socket(); s.setsockopt(socket.SOL_SOCKET, socket.SO_LINGER, struct.pack("ii", 1, 0)); s.bind(("", 0)); print(s.getsockname()[1]); s.close()'` pg_virtualenv -o fsync=off ${env.TMPDIR}/venv/bin/tox -rv"""
             }
             post {
                 always {
@@ -39,6 +47,7 @@ pipeline {
             }
         }
         success {
+            sh "rm -rf ${env.TMPDIR}"
             cleanWs()
         }
     }
diff --git a/tests/settings.py b/tests/settings.py
index 855831b..2a167b4 100644
--- a/tests/settings.py
+++ b/tests/settings.py
@@ -9,3 +9,8 @@ DATABASES = {
         },
     }
 }
+
+if 'postgres' in DATABASES['default']['ENGINE']:
+    for key in ('PGPORT', 'PGHOST', 'PGUSER', 'PGPASSWORD'):
+        if key in os.environ:
+            DATABASES['default'][key[2:]] = os.environ[key]
diff --git a/tox.ini b/tox.ini
index 1566ee8..d2da311 100644
--- a/tox.ini
+++ b/tox.ini
@@ -17,7 +17,15 @@ setenv =
     DJANGO_SETTINGS_MODULE=authentic2.settings
     sqlite: DB_ENGINE=sqlite3
     pg: DB_ENGINE=postgresql_psycopg2
+
+    JUNIT={tty::-o junit_suite_name={envname} --junit-xml=junit-{envname}.xml}
     coverage: COVERAGE=--cov=src --cov-branch --cov-append --cov-report xml --cov-report html
+
+    # support for pg_virtualenv
+    PGPORT={env:PGPORT:}
+    PGHOST={env:PGHOST:}
+    PGUSER={env:PGUSER:}
+    PGPASSWORD={env:PGPASSWORD:}
 usedevelop =
     coverage: true
 deps =
@@ -36,7 +44,7 @@ deps =
     oldldap: python-ldap<3
 commands =
     ./getlasso.sh
-    py.test {env:COVERAGE:} -o junit_suite_name={envname} --junit-xml=junit-{envname}.xml {posargs:tests}
+    py.test {env:COVERAGE:} {env:JUNIT:} {posargs:tests}
 
 [testenv:pylint]
 basepython = python2.7