diff --git a/HACKING.rst b/HACKING.rst
index be894f07..35493e55 100644
--- a/HACKING.rst
+++ b/HACKING.rst
@@ -9,6 +9,7 @@ Nova Style Commandments
 General
 -------
 - Put two newlines between top-level code (funcs, classes, etc)
+- Use only UNIX style newlines ("\n"), not Windows style ("\r\n")
 - Put one newline between methods in classes and anywhere else
 - Long lines should be wrapped in parentheses
   in preference to using a backslash for line continuation.