diff --git a/src/main/java/net/hostsharing/hsadminng/config/Authenticator.java b/src/main/java/net/hostsharing/hsadminng/config/Authenticator.java
new file mode 100644
index 00000000..13f4ada4
--- /dev/null
+++ b/src/main/java/net/hostsharing/hsadminng/config/Authenticator.java
@@ -0,0 +1,8 @@
+package net.hostsharing.hsadminng.config;
+
+import jakarta.servlet.http.HttpServletRequest;
+
+public interface Authenticator {
+
+    String authenticate(final HttpServletRequest httpRequest);
+}
diff --git a/src/main/java/net/hostsharing/hsadminng/config/CasAuthenticator.java b/src/main/java/net/hostsharing/hsadminng/config/CasAuthenticator.java
index 2d0302ee..a048a16c 100644
--- a/src/main/java/net/hostsharing/hsadminng/config/CasAuthenticator.java
+++ b/src/main/java/net/hostsharing/hsadminng/config/CasAuthenticator.java
@@ -16,7 +16,7 @@ import javax.xml.parsers.DocumentBuilderFactory;
 @Service
 @NoArgsConstructor
 @AllArgsConstructor
-public class CasAuthenticator {
+public class CasAuthenticator implements Authenticator {
 
     @Value("${hsadminng.cas.server-url}")
     private String casServerUrl;
@@ -28,11 +28,6 @@ public class CasAuthenticator {
 
     @SneakyThrows
     public String authenticate(final HttpServletRequest httpRequest) {
-        // FIXME: create FakeCasAuthenticator
-        if (casServerUrl.equals("fake")) {
-            return httpRequest.getHeader("current-subject");
-        }
-
         final var ticket = httpRequest.getHeader("Authorization");
         final var url = casServerUrl + "/p3/serviceValidate" +
                 "?service=" + serviceUrl +
diff --git a/src/test/java/net/hostsharing/hsadminng/test/DisableSecurityConfig.java b/src/test/java/net/hostsharing/hsadminng/test/DisableSecurityConfig.java
index 16918eef..978edbb8 100644
--- a/src/test/java/net/hostsharing/hsadminng/test/DisableSecurityConfig.java
+++ b/src/test/java/net/hostsharing/hsadminng/test/DisableSecurityConfig.java
@@ -1,5 +1,6 @@
 package net.hostsharing.hsadminng.test;
 
+import net.hostsharing.hsadminng.config.Authenticator;
 import net.hostsharing.hsadminng.config.CasAuthenticator;
 import org.springframework.boot.test.context.TestConfiguration;
 import org.springframework.context.annotation.Bean;
@@ -19,7 +20,7 @@ public class DisableSecurityConfig {
     }
 
     @Bean
-    public CasAuthenticator casServiceTicketValidator() {
-        return new CasAuthenticator("fake", null);
+    public Authenticator casServiceTicketValidator() {
+        return new FakeAuthenticator();
     }
 }
diff --git a/src/test/java/net/hostsharing/hsadminng/test/FakeAuthenticator.java b/src/test/java/net/hostsharing/hsadminng/test/FakeAuthenticator.java
new file mode 100644
index 00000000..66dcd9a3
--- /dev/null
+++ b/src/test/java/net/hostsharing/hsadminng/test/FakeAuthenticator.java
@@ -0,0 +1,18 @@
+package net.hostsharing.hsadminng.test;
+
+import lombok.SneakyThrows;
+import net.hostsharing.hsadminng.config.Authenticator;
+import net.hostsharing.hsadminng.config.CasAuthenticator;
+import org.springframework.stereotype.Service;
+
+import jakarta.servlet.http.HttpServletRequest;
+
+@Service
+public class FakeAuthenticator implements Authenticator {
+
+    @Override
+    @SneakyThrows
+    public String authenticate(final HttpServletRequest httpRequest) {
+        return httpRequest.getHeader("current-subject");
+    }
+}