diff --git a/artiq/compiler/testbench/embedding.py b/artiq/compiler/testbench/embedding.py
index 52932ff93..abe5f2fd3 100644
--- a/artiq/compiler/testbench/embedding.py
+++ b/artiq/compiler/testbench/embedding.py
@@ -12,15 +12,16 @@ def main():
     else:
         compile_only = False
 
+    ddb_path = os.path.join(os.path.dirname(sys.argv[1]), "device_db.pyon")
+    dmgr = DeviceManager(DeviceDB(ddb_path))
+
     with open(sys.argv[1]) as f:
         testcase_code = compile(f.read(), f.name, "exec")
-        testcase_vars = {'__name__': 'testbench'}
+        testcase_vars = {'__name__': 'testbench', 'dmgr': dmgr}
         exec(testcase_code, testcase_vars)
 
-    ddb_path = os.path.join(os.path.dirname(sys.argv[1]), "device_db.pyon")
-
     try:
-        core = DeviceManager(DeviceDB(ddb_path)).get("core")
+        core = dmgr.get("core")
         if compile_only:
             core.compile(testcase_vars["entrypoint"], (), {})
         else: