diff --git a/content/docs/installation/contents.lr b/content/docs/installation/contents.lr
index cc9787f6..3c3a1566 100644
--- a/content/docs/installation/contents.lr
+++ b/content/docs/installation/contents.lr
@@ -30,7 +30,7 @@ Windows) but the installation is a bit more involved.
 
 You need to make sure you have the following software installed on your computer:
 
-* Python 2.7 (**not** Python 3.x)
+* Python 2.7 (**not** Python 3.x, also `python-dev` is required on Ubuntu)
 * ImageMagick (`brew install imagemagick` or `apt-get install imagemagick`
   can get you this on OS X and Ubuntu respectively, on Windows do `choco
   install imagemagick`, which requires [chocolatey :ext](https://chocolatey.org/),