diff --git a/README.md b/README.md
index 4513b910..831d6c15 100644
--- a/README.md
+++ b/README.md
@@ -116,6 +116,8 @@ Software engineering concepts have been applied in this project:
 - [Dependency inversion](https://en.wikipedia.org/wiki/Dependency_inversion_principle)
 - [Separation of concerns](https://en.wikipedia.org/wiki/Separation_of_concerns)
 - [SOLID Principles](https://en.wikipedia.org/wiki/SOLID)
+- [Fail Fast](https://deviq.com/principles/fail-fast)
+- [Guard Clause](https://deviq.com/design-patterns/guard-clause)
 
 There is a website called [DevIQ](https://deviq.com), it is useful to learn about design concepts.