Build environment

Change-Id: I1625f5ccf69d3cb78033439c411df419b9916cb3
diff --git a/docs/spec.rst b/docs/spec.rst
new file mode 100644
index 0000000..b1733e4
--- /dev/null
+++ b/docs/spec.rst
@@ -0,0 +1,4 @@
+NAC Specification
+=================
+
+TBD