diff --git a/src/vsc/model/source_info.py b/src/vsc/model/source_info.py
index 2e367f3..b6586a1 100644
--- a/src/vsc/model/source_info.py
+++ b/src/vsc/model/source_info.py
@@ -25,7 +25,7 @@ def mk(cls, levels=1):
         if len(stack) <= (levels+1):
             raise Exception("requested stack frame %d out-of-bounds (%d)" % (
                 levels, len(stack)))
-        frame = inspect.stack()[levels+1]
+        frame = stack[levels+1]
         
         return cls(frame.filename, frame.lineno)