diff --git a/free-programming-books.md b/free-programming-books.md
index 796c39969caf424c19f0e2221785d24d77b45ff1..5e547ea1525ab99dd48885b4dc35aab74ff14b93 100644
--- a/free-programming-books.md
+++ b/free-programming-books.md
@@ -139,6 +139,7 @@
 * [Wikibooks: Programming](http://en.wikibooks.org/wiki/Category%3aComputer_programming)
 * [JSBooks - directory of free javascript ebooks](https://github.com/revolunet/JSbooks)
 * [Learn X in Y minutes](http://learnxinyminutes.com/)
+* [Messaging as a Programming Model](https://leanpub.com/messaging_as_a_programming_model)
 
 
 ###Graphics Programming