--- bin/activate	2017-01-22 21:54:38.397178514 -0800
+++ bin/activate	2016-01-09 20:19:15.528759407 -0800
@@ -37,7 +37,19 @@
 # unset irrelavent variables
 deactivate nondestructive
 
-VIRTUAL_ENV="${S}/pyvenv"
+# Chances are we have pyvenv-auto.sh sourced which provides
+# functionality to find a pyvenv. Only if that is not the case we simply
+# use PWD as the virtual env path (which might be wrong if we did not
+# cd into the root of a virtual env; that is assumed to be good enough
+# an approach).
+if declare -F _pyvenv_find_venv > /dev/null; then
+  VIRTUAL_ENV=$(_pyvenv_find_venv "${PWD}")
+else
+  VIRTUAL_ENV="${PWD}"
+fi
+if [ -z "${VIRTUAL_ENV}" ]; then
+  echo "No virtual env found"
+fi
 export VIRTUAL_ENV
 
 _OLD_VIRTUAL_PATH="$PATH"