fix sys.path for local workers Fixes #421

src/xdist/plugin.py

@@ -1,9 +1,12 @@
 import os
 import uuid
+import sys
 
 import py
 import pytest
 
+_sys_path = list(sys.path)  # freeze a copy of sys.path at interpreter startup
+
 
 def pytest_xdist_auto_num_workers():
     try: