diff --git a/README.md b/README.md
index af53364..fb4cad7 100644
--- a/README.md
+++ b/README.md
@@ -386,6 +386,7 @@ Please see [CONTRIBUTING](https://github.com/ziadoz/awesome-php/blob/master/CONT
 * [Monad PHP](https://github.com/ircmaxell/monad-php) - A simple Monad library.
 * [Patchwork](http://antecedent.github.io/patchwork/) - A library for redefining userland functions.
 * [PHP Option](https://github.com/schmittjoh/php-option) - An option type library.
+* [PhpDeal](https://github.com/lisachenko/php-deal) - Design by contract library.
 * [Pipeline](https://github.com/thephpleague/pipeline) - A pipeline pattern implementation.
 * [Ruler](https://github.com/bobthecow/Ruler) - A simple stateless production rules engine.
 * [RulerZ](https://github.com/K-Phoen/rulerz) - A powerful rule engine and implementation of the Specification pattern.