diff --git a/tests/__init__.py b/tests/__init__.py
index <HASH>..<HASH> 100644
--- a/tests/__init__.py
+++ b/tests/__init__.py
@@ -0,0 +1,25 @@
+import os
+import logging
+
+
+try:
+    with open('build/env-vars') as env_file:
+        for line_num, line in enumerate(env_file):
+            if line.startswith('export '):
+                line = line[7:].strip()
+            name, sep, value = line.partition('=')
+            name, value = name.strip(), value.strip()
+            if sep != '=':
+                logging.warning('ignoring line %d in environment file - %s',
+                                line_num, line)
+                continue
+
+            if value:
+                logging.info('setting environment variable %s = %r',
+                             name, value)
+                os.environ[name] = value
+            else:
+                logging.info('clearing environment variable %s', name)
+                os.environ.pop('name', None)
+except IOError:
+    logging.info('expected environment file at build/env-vars')
tests: Read environment from build/env-vars.