From 6f65ad0b97f8f7b7dc9c20cab842a372a296d7b8 Mon Sep 17 00:00:00 2001
From: Kenneth Reitz <me@kennethreitz.com>
Date: Wed, 2 Jan 2013 22:22:07 -0500
Subject: [PATCH] Update Readme.md

---
 Readme.md | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/Readme.md b/Readme.md
index 9d7d711..ebdb847 100644
--- a/Readme.md
+++ b/Readme.md
@@ -38,3 +38,17 @@ You can also add it to upcoming builds of an existing application:
 The buildpack will detect your app as Python if it has the file `requirements.txt` in the root. 
 
 It will use Pip to install your dependencies, vendoring a copy of the Python runtime into your slug. 
+
+Specify a Runtime
+-----------------
+
+You can also provide arbitrary releases Python with a `runtime.txt` file.
+
+    $ cat runtime.txt
+    python-3.3.0
+    
+Runtime options include:
+
+- python-2.7.3
+- python-3.3.0
+- pypy-1.9 (experimental)