diff --git a/src/main/java/org/gcube/common/security/credentials/Credentials.java b/src/main/java/org/gcube/common/security/credentials/Credentials.java
new file mode 100644
index 0000000..c14113e
--- /dev/null
+++ b/src/main/java/org/gcube/common/security/credentials/Credentials.java
@@ -0,0 +1,5 @@
+package org.gcube.common.security.credentials;
+
+public interface Credentials {
+
+}
diff --git a/src/main/java/org/gcube/common/security/secrets/Secret.java b/src/main/java/org/gcube/common/security/secrets/Secret.java
index a9813bf..84778a1 100644
--- a/src/main/java/org/gcube/common/security/secrets/Secret.java
+++ b/src/main/java/org/gcube/common/security/secrets/Secret.java
@@ -16,5 +16,5 @@ public abstract class Secret {
 	public abstract Map<String,String> getHTTPAuthorizationHeaders();
 		
 	public abstract boolean isExpired();
-		
+	
 }