[DOC] Specify magic version

docs/source/index.rst

diff --git a/docs/source/index.rst b/docs/source/index.rst
index 7573edb..fa3f806 100644
--- a/docs/source/index.rst
+++ b/docs/source/index.rst
@@ -162,6 +162,7 @@
 - Build the pdk natively. 
 
 Make sure you have `Magic VLSI Layout Tool <http://opencircuitdesign.com/magic/index.html>`__ installed on your machine before building the pdk. 
+The pdk build is tested with magic version `8.3.209`. 
 
 .. code:: bash