--- a/nbproject/project.xml	Tue Nov 28 18:59:13 2017 +0100
+++ b/nbproject/project.xml	Sun Dec 10 16:10:14 2017 +0100
@@ -10,6 +10,10 @@
                     <file>${libs.jstl.classpath}</file>
                     <path-in-war>WEB-INF/lib</path-in-war>
                 </library>
+                <library dirs="200">
+                    <file>${libs.SLF4J-JDK.classpath}</file>
+                    <path-in-war>WEB-INF/lib</path-in-war>
+                </library>
             </web-module-libraries>
             <web-module-additional-libraries/>
             <source-roots>