diff --git a/README.md b/README.md
index 878177f..6485b0b 100644
--- a/README.md
+++ b/README.md
@@ -5,3 +5,8 @@
 This is the companion code to my eBook [Get Your Hands Dirty on Clean Architecture](https://leanpub.com/get-your-hands-dirty-on-clean-architecture).
 
 It implements a domain-centric "Hexagonal" approach of a common web application with Java and Spring Boot. 
+
+## Prerequisites
+
+* JDK 8
+* this project uses Lombok, so enable annotation processing in your IDE
diff --git a/build.gradle b/build.gradle
index a7e797e..ab97ad2 100644
--- a/build.gradle
+++ b/build.gradle
@@ -21,4 +21,9 @@ subprojects {
         }
     }
 
+    compileJava {
+        sourceCompatibility = 1.8
+        targetCompatibility = 1.8
+    }
+
 }