diff --git a/src/main/java/org/owasp/webgoat/container/assignments/AssignmentEndpoint.java b/src/main/java/org/owasp/webgoat/container/assignments/AssignmentEndpoint.java
index da3edbab5..9f81039fe 100644
--- a/src/main/java/org/owasp/webgoat/container/assignments/AssignmentEndpoint.java
+++ b/src/main/java/org/owasp/webgoat/container/assignments/AssignmentEndpoint.java
@@ -25,4 +25,4 @@
 
 package org.owasp.webgoat.container.assignments;
 
-public abstract class AssignmentEndpoint {}
+public interface AssignmentEndpoint {}
diff --git a/src/main/java/org/owasp/webgoat/container/assignments/AttackResult.java b/src/main/java/org/owasp/webgoat/container/assignments/AttackResult.java
index 2473533f4..e9fcd1196 100644
--- a/src/main/java/org/owasp/webgoat/container/assignments/AttackResult.java
+++ b/src/main/java/org/owasp/webgoat/container/assignments/AttackResult.java
@@ -41,7 +41,7 @@ public class AttackResult {
   private final String assignment;
   private boolean attemptWasMade;
 
-  public AttackResult(
+  private AttackResult(
       boolean lessonCompleted,
       String feedback,
       String output,
diff --git a/src/main/java/org/owasp/webgoat/container/assignments/AttackResultBuilder.java b/src/main/java/org/owasp/webgoat/container/assignments/AttackResultBuilder.java
index b7367dcdc..99e06a5cd 100644
--- a/src/main/java/org/owasp/webgoat/container/assignments/AttackResultBuilder.java
+++ b/src/main/java/org/owasp/webgoat/container/assignments/AttackResultBuilder.java
@@ -96,14 +96,6 @@ public class AttackResultBuilder {
    * @return a builder for creating a result from a lesson
    * @param assignment
    */
-  public AttackResultBuilder oldSuccess(AssignmentEndpoint assignment) {
-    return this.lessonCompleted(true)
-        .assignmentCompleted(true)
-        .attemptWasMade()
-        .feedback("assignment.solved")
-        .assignment(assignment);
-  }
-
   public static AttackResultBuilder success(AssignmentEndpoint assignment) {
     return new AttackResultBuilder()
         .lessonCompleted(true)
diff --git a/src/main/java/org/owasp/webgoat/lessons/authbypass/VerifyAccount.java b/src/main/java/org/owasp/webgoat/lessons/authbypass/VerifyAccount.java
index 8210e459f..41e6e4e0c 100644
--- a/src/main/java/org/owasp/webgoat/lessons/authbypass/VerifyAccount.java
+++ b/src/main/java/org/owasp/webgoat/lessons/authbypass/VerifyAccount.java
@@ -49,7 +49,7 @@ import org.springframework.web.bind.annotation.RestController;
   "auth-bypass.hints.verify.3",
   "auth-bypass.hints.verify.4"
 })
-public class VerifyAccount extends AssignmentEndpoint {
+public class VerifyAccount implements AssignmentEndpoint {
 
   private final LessonSession userSessionData;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/bypassrestrictions/BypassRestrictionsFieldRestrictions.java b/src/main/java/org/owasp/webgoat/lessons/bypassrestrictions/BypassRestrictionsFieldRestrictions.java
index 0178d5a2a..9f28f2305 100644
--- a/src/main/java/org/owasp/webgoat/lessons/bypassrestrictions/BypassRestrictionsFieldRestrictions.java
+++ b/src/main/java/org/owasp/webgoat/lessons/bypassrestrictions/BypassRestrictionsFieldRestrictions.java
@@ -33,7 +33,7 @@ import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.bind.annotation.RestController;
 
 @RestController
-public class BypassRestrictionsFieldRestrictions extends AssignmentEndpoint {
+public class BypassRestrictionsFieldRestrictions implements AssignmentEndpoint {
 
   @PostMapping("/BypassRestrictions/FieldRestrictions")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/bypassrestrictions/BypassRestrictionsFrontendValidation.java b/src/main/java/org/owasp/webgoat/lessons/bypassrestrictions/BypassRestrictionsFrontendValidation.java
index cbf2f3948..71f200228 100644
--- a/src/main/java/org/owasp/webgoat/lessons/bypassrestrictions/BypassRestrictionsFrontendValidation.java
+++ b/src/main/java/org/owasp/webgoat/lessons/bypassrestrictions/BypassRestrictionsFrontendValidation.java
@@ -33,7 +33,7 @@ import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.bind.annotation.RestController;
 
 @RestController
-public class BypassRestrictionsFrontendValidation extends AssignmentEndpoint {
+public class BypassRestrictionsFrontendValidation implements AssignmentEndpoint {
 
   @PostMapping("/BypassRestrictions/frontendValidation")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/challenges/FlagController.java b/src/main/java/org/owasp/webgoat/lessons/challenges/FlagController.java
index d7af3d9df..81bb924d6 100644
--- a/src/main/java/org/owasp/webgoat/lessons/challenges/FlagController.java
+++ b/src/main/java/org/owasp/webgoat/lessons/challenges/FlagController.java
@@ -34,7 +34,7 @@ import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.bind.annotation.RestController;
 
 @RestController
-public class FlagController extends AssignmentEndpoint {
+public class FlagController implements AssignmentEndpoint {
 
   private final Flags flags;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/challenges/challenge1/Assignment1.java b/src/main/java/org/owasp/webgoat/lessons/challenges/challenge1/Assignment1.java
index 84456ff31..0b79c0b16 100644
--- a/src/main/java/org/owasp/webgoat/lessons/challenges/challenge1/Assignment1.java
+++ b/src/main/java/org/owasp/webgoat/lessons/challenges/challenge1/Assignment1.java
@@ -43,7 +43,7 @@ import org.springframework.web.bind.annotation.RestController;
  * @since August 11, 2016
  */
 @RestController
-public class Assignment1 extends AssignmentEndpoint {
+public class Assignment1 implements AssignmentEndpoint {
 
   private final Flags flags;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/challenges/challenge5/Assignment5.java b/src/main/java/org/owasp/webgoat/lessons/challenges/challenge5/Assignment5.java
index d1d00b854..db52392bf 100644
--- a/src/main/java/org/owasp/webgoat/lessons/challenges/challenge5/Assignment5.java
+++ b/src/main/java/org/owasp/webgoat/lessons/challenges/challenge5/Assignment5.java
@@ -42,7 +42,7 @@ import org.springframework.web.bind.annotation.RestController;
 @RestController
 @Slf4j
 @RequiredArgsConstructor
-public class Assignment5 extends AssignmentEndpoint {
+public class Assignment5 implements AssignmentEndpoint {
 
   private final LessonDataSource dataSource;
   private final Flags flags;
diff --git a/src/main/java/org/owasp/webgoat/lessons/challenges/challenge7/Assignment7.java b/src/main/java/org/owasp/webgoat/lessons/challenges/challenge7/Assignment7.java
index 96c0c9bda..fab9d7482 100644
--- a/src/main/java/org/owasp/webgoat/lessons/challenges/challenge7/Assignment7.java
+++ b/src/main/java/org/owasp/webgoat/lessons/challenges/challenge7/Assignment7.java
@@ -31,7 +31,7 @@ import org.springframework.web.client.RestTemplate;
  */
 @RestController
 @Slf4j
-public class Assignment7 extends AssignmentEndpoint {
+public class Assignment7 implements AssignmentEndpoint {
 
   public static final String ADMIN_PASSWORD_LINK = "375afe1104f4a487a73823c50a9292a2";
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/challenges/challenge8/Assignment8.java b/src/main/java/org/owasp/webgoat/lessons/challenges/challenge8/Assignment8.java
index 6623ea1a0..0bf9edeb9 100644
--- a/src/main/java/org/owasp/webgoat/lessons/challenges/challenge8/Assignment8.java
+++ b/src/main/java/org/owasp/webgoat/lessons/challenges/challenge8/Assignment8.java
@@ -19,7 +19,7 @@ import org.springframework.web.bind.annotation.RestController;
 @RestController
 @Slf4j
 @RequiredArgsConstructor
-public class Assignment8 extends AssignmentEndpoint {
+public class Assignment8 implements AssignmentEndpoint {
 
   private static final Map<Integer, Integer> votes = new HashMap<>();
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/chromedevtools/NetworkDummy.java b/src/main/java/org/owasp/webgoat/lessons/chromedevtools/NetworkDummy.java
index 491c2d7a7..cff6ab647 100644
--- a/src/main/java/org/owasp/webgoat/lessons/chromedevtools/NetworkDummy.java
+++ b/src/main/java/org/owasp/webgoat/lessons/chromedevtools/NetworkDummy.java
@@ -40,7 +40,7 @@ import org.springframework.web.bind.annotation.RestController;
  * @since 30.11.18
  */
 @RestController
-public class NetworkDummy extends AssignmentEndpoint {
+public class NetworkDummy implements AssignmentEndpoint {
 
   private final LessonSession lessonSession;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/chromedevtools/NetworkLesson.java b/src/main/java/org/owasp/webgoat/lessons/chromedevtools/NetworkLesson.java
index 817e20dbc..106c03ceb 100644
--- a/src/main/java/org/owasp/webgoat/lessons/chromedevtools/NetworkLesson.java
+++ b/src/main/java/org/owasp/webgoat/lessons/chromedevtools/NetworkLesson.java
@@ -43,7 +43,7 @@ import org.springframework.web.bind.annotation.RestController;
  */
 @RestController
 @AssignmentHints({"networkHint1", "networkHint2"})
-public class NetworkLesson extends AssignmentEndpoint {
+public class NetworkLesson implements AssignmentEndpoint {
 
   @PostMapping(
       value = "/ChromeDevTools/network",
diff --git a/src/main/java/org/owasp/webgoat/lessons/cia/CIAQuiz.java b/src/main/java/org/owasp/webgoat/lessons/cia/CIAQuiz.java
index 377c12a2c..35d462d24 100644
--- a/src/main/java/org/owasp/webgoat/lessons/cia/CIAQuiz.java
+++ b/src/main/java/org/owasp/webgoat/lessons/cia/CIAQuiz.java
@@ -12,7 +12,7 @@ import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.bind.annotation.RestController;
 
 @RestController
-public class CIAQuiz extends AssignmentEndpoint {
+public class CIAQuiz implements AssignmentEndpoint {
 
   private final String[] solutions = {"Solution 3", "Solution 1", "Solution 4", "Solution 2"};
   boolean[] guesses = new boolean[solutions.length];
diff --git a/src/main/java/org/owasp/webgoat/lessons/clientsidefiltering/ClientSideFilteringAssignment.java b/src/main/java/org/owasp/webgoat/lessons/clientsidefiltering/ClientSideFilteringAssignment.java
index f786deb54..6dcb154c8 100644
--- a/src/main/java/org/owasp/webgoat/lessons/clientsidefiltering/ClientSideFilteringAssignment.java
+++ b/src/main/java/org/owasp/webgoat/lessons/clientsidefiltering/ClientSideFilteringAssignment.java
@@ -40,7 +40,7 @@ import org.springframework.web.bind.annotation.RestController;
   "ClientSideFilteringHint3",
   "ClientSideFilteringHint4"
 })
-public class ClientSideFilteringAssignment extends AssignmentEndpoint {
+public class ClientSideFilteringAssignment implements AssignmentEndpoint {
 
   @PostMapping("/clientSideFiltering/attack1")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/clientsidefiltering/ClientSideFilteringFreeAssignment.java b/src/main/java/org/owasp/webgoat/lessons/clientsidefiltering/ClientSideFilteringFreeAssignment.java
index 9bd11d61b..bc4a66ca1 100644
--- a/src/main/java/org/owasp/webgoat/lessons/clientsidefiltering/ClientSideFilteringFreeAssignment.java
+++ b/src/main/java/org/owasp/webgoat/lessons/clientsidefiltering/ClientSideFilteringFreeAssignment.java
@@ -43,7 +43,7 @@ import org.springframework.web.bind.annotation.RestController;
   "client.side.filtering.free.hint2",
   "client.side.filtering.free.hint3"
 })
-public class ClientSideFilteringFreeAssignment extends AssignmentEndpoint {
+public class ClientSideFilteringFreeAssignment implements AssignmentEndpoint {
   public static final String SUPER_COUPON_CODE = "get_it_for_free";
 
   @PostMapping("/clientSideFiltering/getItForFree")
diff --git a/src/main/java/org/owasp/webgoat/lessons/cryptography/EncodingAssignment.java b/src/main/java/org/owasp/webgoat/lessons/cryptography/EncodingAssignment.java
index 23546e4ca..4df2b97e2 100644
--- a/src/main/java/org/owasp/webgoat/lessons/cryptography/EncodingAssignment.java
+++ b/src/main/java/org/owasp/webgoat/lessons/cryptography/EncodingAssignment.java
@@ -38,7 +38,7 @@ import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.bind.annotation.RestController;
 
 @RestController
-public class EncodingAssignment extends AssignmentEndpoint {
+public class EncodingAssignment implements AssignmentEndpoint {
 
   public static String getBasicAuth(String username, String password) {
     return Base64.getEncoder().encodeToString(username.concat(":").concat(password).getBytes());
diff --git a/src/main/java/org/owasp/webgoat/lessons/cryptography/HashingAssignment.java b/src/main/java/org/owasp/webgoat/lessons/cryptography/HashingAssignment.java
index dde490858..19f00b748 100644
--- a/src/main/java/org/owasp/webgoat/lessons/cryptography/HashingAssignment.java
+++ b/src/main/java/org/owasp/webgoat/lessons/cryptography/HashingAssignment.java
@@ -42,7 +42,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 @RestController
 @AssignmentHints({"crypto-hashing.hints.1", "crypto-hashing.hints.2"})
-public class HashingAssignment extends AssignmentEndpoint {
+public class HashingAssignment implements AssignmentEndpoint {
   public static final String[] SECRETS = {"secret", "admin", "password", "123456", "passw0rd"};
 
   @RequestMapping(path = "/crypto/hashing/md5", produces = MediaType.TEXT_HTML_VALUE)
diff --git a/src/main/java/org/owasp/webgoat/lessons/cryptography/SecureDefaultsAssignment.java b/src/main/java/org/owasp/webgoat/lessons/cryptography/SecureDefaultsAssignment.java
index 01cad0b34..d30708bbc 100644
--- a/src/main/java/org/owasp/webgoat/lessons/cryptography/SecureDefaultsAssignment.java
+++ b/src/main/java/org/owasp/webgoat/lessons/cryptography/SecureDefaultsAssignment.java
@@ -40,7 +40,7 @@ import org.springframework.web.bind.annotation.RestController;
   "crypto-secure-defaults.hints.2",
   "crypto-secure-defaults.hints.3"
 })
-public class SecureDefaultsAssignment extends AssignmentEndpoint {
+public class SecureDefaultsAssignment implements AssignmentEndpoint {
 
   @PostMapping("/crypto/secure/defaults")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/cryptography/SigningAssignment.java b/src/main/java/org/owasp/webgoat/lessons/cryptography/SigningAssignment.java
index 64d62c481..7a27cae61 100644
--- a/src/main/java/org/owasp/webgoat/lessons/cryptography/SigningAssignment.java
+++ b/src/main/java/org/owasp/webgoat/lessons/cryptography/SigningAssignment.java
@@ -50,7 +50,7 @@ import org.springframework.web.bind.annotation.RestController;
   "crypto-signing.hints.4"
 })
 @Slf4j
-public class SigningAssignment extends AssignmentEndpoint {
+public class SigningAssignment implements AssignmentEndpoint {
 
   @RequestMapping(path = "/crypto/signing/getprivate", produces = MediaType.TEXT_HTML_VALUE)
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/cryptography/XOREncodingAssignment.java b/src/main/java/org/owasp/webgoat/lessons/cryptography/XOREncodingAssignment.java
index e77c5b093..a2807b4e6 100644
--- a/src/main/java/org/owasp/webgoat/lessons/cryptography/XOREncodingAssignment.java
+++ b/src/main/java/org/owasp/webgoat/lessons/cryptography/XOREncodingAssignment.java
@@ -35,7 +35,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 @RestController
 @AssignmentHints({"crypto-encoding-xor.hints.1"})
-public class XOREncodingAssignment extends AssignmentEndpoint {
+public class XOREncodingAssignment implements AssignmentEndpoint {
 
   @PostMapping("/crypto/encoding/xor")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/csrf/CSRFConfirmFlag1.java b/src/main/java/org/owasp/webgoat/lessons/csrf/CSRFConfirmFlag1.java
index 00ea70878..f46c23862 100644
--- a/src/main/java/org/owasp/webgoat/lessons/csrf/CSRFConfirmFlag1.java
+++ b/src/main/java/org/owasp/webgoat/lessons/csrf/CSRFConfirmFlag1.java
@@ -36,7 +36,7 @@ import org.springframework.web.bind.annotation.RestController;
 /** Created by jason on 9/29/17. */
 @RestController
 @AssignmentHints({"csrf-get.hint1", "csrf-get.hint2", "csrf-get.hint3", "csrf-get.hint4"})
-public class CSRFConfirmFlag1 extends AssignmentEndpoint {
+public class CSRFConfirmFlag1 implements AssignmentEndpoint {
 
   private final LessonSession userSessionData;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/csrf/CSRFFeedback.java b/src/main/java/org/owasp/webgoat/lessons/csrf/CSRFFeedback.java
index 5960b430e..2154ed34d 100644
--- a/src/main/java/org/owasp/webgoat/lessons/csrf/CSRFFeedback.java
+++ b/src/main/java/org/owasp/webgoat/lessons/csrf/CSRFFeedback.java
@@ -46,7 +46,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 @RestController
 @AssignmentHints({"csrf-feedback-hint1", "csrf-feedback-hint2", "csrf-feedback-hint3"})
-public class CSRFFeedback extends AssignmentEndpoint {
+public class CSRFFeedback implements AssignmentEndpoint {
 
   private final LessonSession userSessionData;
   private final ObjectMapper objectMapper;
diff --git a/src/main/java/org/owasp/webgoat/lessons/csrf/CSRFLogin.java b/src/main/java/org/owasp/webgoat/lessons/csrf/CSRFLogin.java
index 665efc6ee..78fb16a10 100644
--- a/src/main/java/org/owasp/webgoat/lessons/csrf/CSRFLogin.java
+++ b/src/main/java/org/owasp/webgoat/lessons/csrf/CSRFLogin.java
@@ -35,7 +35,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 @RestController
 @AssignmentHints({"csrf-login-hint1", "csrf-login-hint2", "csrf-login-hint3"})
-public class CSRFLogin extends AssignmentEndpoint {
+public class CSRFLogin implements AssignmentEndpoint {
 
   @PostMapping(
       path = "/csrf/login",
diff --git a/src/main/java/org/owasp/webgoat/lessons/csrf/ForgedReviews.java b/src/main/java/org/owasp/webgoat/lessons/csrf/ForgedReviews.java
index 33e7fb8bc..50dcb8915 100644
--- a/src/main/java/org/owasp/webgoat/lessons/csrf/ForgedReviews.java
+++ b/src/main/java/org/owasp/webgoat/lessons/csrf/ForgedReviews.java
@@ -47,7 +47,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 @RestController
 @AssignmentHints({"csrf-review-hint1", "csrf-review-hint2", "csrf-review-hint3"})
-public class ForgedReviews extends AssignmentEndpoint {
+public class ForgedReviews implements AssignmentEndpoint {
 
   private static DateTimeFormatter fmt = DateTimeFormatter.ofPattern("yyyy-MM-dd, HH:mm:ss");
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/deserialization/InsecureDeserializationTask.java b/src/main/java/org/owasp/webgoat/lessons/deserialization/InsecureDeserializationTask.java
index df7c4d0fb..22dd18a1f 100644
--- a/src/main/java/org/owasp/webgoat/lessons/deserialization/InsecureDeserializationTask.java
+++ b/src/main/java/org/owasp/webgoat/lessons/deserialization/InsecureDeserializationTask.java
@@ -45,7 +45,7 @@ import org.springframework.web.bind.annotation.RestController;
   "insecure-deserialization.hints.2",
   "insecure-deserialization.hints.3"
 })
-public class InsecureDeserializationTask extends AssignmentEndpoint {
+public class InsecureDeserializationTask implements AssignmentEndpoint {
 
   @PostMapping("/InsecureDeserialization/task")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/hijacksession/HijackSessionAssignment.java b/src/main/java/org/owasp/webgoat/lessons/hijacksession/HijackSessionAssignment.java
index ab1a583d8..7817022f0 100644
--- a/src/main/java/org/owasp/webgoat/lessons/hijacksession/HijackSessionAssignment.java
+++ b/src/main/java/org/owasp/webgoat/lessons/hijacksession/HijackSessionAssignment.java
@@ -53,7 +53,7 @@ import org.springframework.web.bind.annotation.RestController;
   "hijacksession.hints.4",
   "hijacksession.hints.5"
 })
-public class HijackSessionAssignment extends AssignmentEndpoint {
+public class HijackSessionAssignment implements AssignmentEndpoint {
   private static final String COOKIE_NAME = "hijack_cookie";
 
   private final HijackSessionAuthenticationProvider provider;
diff --git a/src/main/java/org/owasp/webgoat/lessons/htmltampering/HtmlTamperingTask.java b/src/main/java/org/owasp/webgoat/lessons/htmltampering/HtmlTamperingTask.java
index 0cd73c037..2042ea0f6 100644
--- a/src/main/java/org/owasp/webgoat/lessons/htmltampering/HtmlTamperingTask.java
+++ b/src/main/java/org/owasp/webgoat/lessons/htmltampering/HtmlTamperingTask.java
@@ -35,7 +35,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 @RestController
 @AssignmentHints({"hint1", "hint2", "hint3"})
-public class HtmlTamperingTask extends AssignmentEndpoint {
+public class HtmlTamperingTask implements AssignmentEndpoint {
 
   @PostMapping("/HtmlTampering/task")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/httpbasics/HttpBasicsLesson.java b/src/main/java/org/owasp/webgoat/lessons/httpbasics/HttpBasicsLesson.java
index c1d56e171..f73e3ae06 100644
--- a/src/main/java/org/owasp/webgoat/lessons/httpbasics/HttpBasicsLesson.java
+++ b/src/main/java/org/owasp/webgoat/lessons/httpbasics/HttpBasicsLesson.java
@@ -35,7 +35,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 @RestController
 @AssignmentHints({"http-basics.hints.http_basics_lesson.1"})
-public class HttpBasicsLesson extends AssignmentEndpoint {
+public class HttpBasicsLesson implements AssignmentEndpoint {
 
   @PostMapping("/HttpBasics/attack1")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/httpbasics/HttpBasicsQuiz.java b/src/main/java/org/owasp/webgoat/lessons/httpbasics/HttpBasicsQuiz.java
index ce80179e7..eb497c7e6 100644
--- a/src/main/java/org/owasp/webgoat/lessons/httpbasics/HttpBasicsQuiz.java
+++ b/src/main/java/org/owasp/webgoat/lessons/httpbasics/HttpBasicsQuiz.java
@@ -37,7 +37,7 @@ import org.springframework.web.bind.annotation.RestController;
 @RestController
 @AssignmentHints({"http-basics.hints.http_basic_quiz.1", "http-basics.hints.http_basic_quiz.2"})
 @AssignmentPath("HttpBasics/attack2")
-public class HttpBasicsQuiz extends AssignmentEndpoint {
+public class HttpBasicsQuiz implements AssignmentEndpoint {
 
   @PostMapping("/HttpBasics/attack2")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/httpproxies/HttpBasicsInterceptRequest.java b/src/main/java/org/owasp/webgoat/lessons/httpproxies/HttpBasicsInterceptRequest.java
index f8f85a7f8..3731dec4e 100644
--- a/src/main/java/org/owasp/webgoat/lessons/httpproxies/HttpBasicsInterceptRequest.java
+++ b/src/main/java/org/owasp/webgoat/lessons/httpproxies/HttpBasicsInterceptRequest.java
@@ -37,7 +37,7 @@ import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.bind.annotation.RestController;
 
 @RestController
-public class HttpBasicsInterceptRequest extends AssignmentEndpoint {
+public class HttpBasicsInterceptRequest implements AssignmentEndpoint {
 
   @RequestMapping(
       path = "/HttpProxies/intercept-request",
diff --git a/src/main/java/org/owasp/webgoat/lessons/idor/IDORDiffAttributes.java b/src/main/java/org/owasp/webgoat/lessons/idor/IDORDiffAttributes.java
index 00885761b..7b641a228 100644
--- a/src/main/java/org/owasp/webgoat/lessons/idor/IDORDiffAttributes.java
+++ b/src/main/java/org/owasp/webgoat/lessons/idor/IDORDiffAttributes.java
@@ -40,7 +40,7 @@ import org.springframework.web.bind.annotation.RestController;
   "idor.hints.idorDiffAttributes2",
   "idor.hints.idorDiffAttributes3"
 })
-public class IDORDiffAttributes extends AssignmentEndpoint {
+public class IDORDiffAttributes implements AssignmentEndpoint {
 
   @PostMapping("/IDOR/diff-attributes")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/idor/IDOREditOtherProfile.java b/src/main/java/org/owasp/webgoat/lessons/idor/IDOREditOtherProfile.java
index 720491c5d..e0b9debf8 100644
--- a/src/main/java/org/owasp/webgoat/lessons/idor/IDOREditOtherProfile.java
+++ b/src/main/java/org/owasp/webgoat/lessons/idor/IDOREditOtherProfile.java
@@ -48,7 +48,7 @@ import org.springframework.web.bind.annotation.RestController;
   "idor.hints.otherProfile8",
   "idor.hints.otherProfile9"
 })
-public class IDOREditOtherProfile extends AssignmentEndpoint {
+public class IDOREditOtherProfile implements AssignmentEndpoint {
 
   private final LessonSession userSessionData;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/idor/IDORLogin.java b/src/main/java/org/owasp/webgoat/lessons/idor/IDORLogin.java
index 77158c43d..febfb2f50 100644
--- a/src/main/java/org/owasp/webgoat/lessons/idor/IDORLogin.java
+++ b/src/main/java/org/owasp/webgoat/lessons/idor/IDORLogin.java
@@ -39,7 +39,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 @RestController
 @AssignmentHints({"idor.hints.idor_login"})
-public class IDORLogin extends AssignmentEndpoint {
+public class IDORLogin implements AssignmentEndpoint {
   private final LessonSession lessonSession;
 
   public IDORLogin(LessonSession lessonSession) {
diff --git a/src/main/java/org/owasp/webgoat/lessons/idor/IDORViewOtherProfile.java b/src/main/java/org/owasp/webgoat/lessons/idor/IDORViewOtherProfile.java
index 0be4563bb..2bd783807 100644
--- a/src/main/java/org/owasp/webgoat/lessons/idor/IDORViewOtherProfile.java
+++ b/src/main/java/org/owasp/webgoat/lessons/idor/IDORViewOtherProfile.java
@@ -47,7 +47,7 @@ import org.springframework.web.bind.annotation.RestController;
   "idor.hints.otherProfile8",
   "idor.hints.otherProfile9"
 })
-public class IDORViewOtherProfile extends AssignmentEndpoint {
+public class IDORViewOtherProfile implements AssignmentEndpoint {
 
   private final LessonSession userSessionData;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/idor/IDORViewOwnProfileAltUrl.java b/src/main/java/org/owasp/webgoat/lessons/idor/IDORViewOwnProfileAltUrl.java
index 964657c8a..970b33932 100644
--- a/src/main/java/org/owasp/webgoat/lessons/idor/IDORViewOwnProfileAltUrl.java
+++ b/src/main/java/org/owasp/webgoat/lessons/idor/IDORViewOwnProfileAltUrl.java
@@ -41,7 +41,7 @@ import org.springframework.web.bind.annotation.RestController;
   "idor.hints.ownProfileAltUrl2",
   "idor.hints.ownProfileAltUrl3"
 })
-public class IDORViewOwnProfileAltUrl extends AssignmentEndpoint {
+public class IDORViewOwnProfileAltUrl implements AssignmentEndpoint {
   private final LessonSession userSessionData;
 
   public IDORViewOwnProfileAltUrl(LessonSession userSessionData) {
diff --git a/src/main/java/org/owasp/webgoat/lessons/insecurelogin/InsecureLoginTask.java b/src/main/java/org/owasp/webgoat/lessons/insecurelogin/InsecureLoginTask.java
index 8478105b5..24f5ac7f6 100644
--- a/src/main/java/org/owasp/webgoat/lessons/insecurelogin/InsecureLoginTask.java
+++ b/src/main/java/org/owasp/webgoat/lessons/insecurelogin/InsecureLoginTask.java
@@ -31,7 +31,7 @@ import org.springframework.http.HttpStatus;
 import org.springframework.web.bind.annotation.*;
 
 @RestController
-public class InsecureLoginTask extends AssignmentEndpoint {
+public class InsecureLoginTask implements AssignmentEndpoint {
 
   @PostMapping("/InsecureLogin/task")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/jwt/JWTDecodeEndpoint.java b/src/main/java/org/owasp/webgoat/lessons/jwt/JWTDecodeEndpoint.java
index d052000d2..75bfd6171 100644
--- a/src/main/java/org/owasp/webgoat/lessons/jwt/JWTDecodeEndpoint.java
+++ b/src/main/java/org/owasp/webgoat/lessons/jwt/JWTDecodeEndpoint.java
@@ -11,7 +11,7 @@ import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.bind.annotation.RestController;
 
 @RestController
-public class JWTDecodeEndpoint extends AssignmentEndpoint {
+public class JWTDecodeEndpoint implements AssignmentEndpoint {
 
   @PostMapping("/JWT/decode")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/jwt/JWTQuiz.java b/src/main/java/org/owasp/webgoat/lessons/jwt/JWTQuiz.java
index d0286a24c..d73765cb4 100644
--- a/src/main/java/org/owasp/webgoat/lessons/jwt/JWTQuiz.java
+++ b/src/main/java/org/owasp/webgoat/lessons/jwt/JWTQuiz.java
@@ -12,7 +12,7 @@ import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.bind.annotation.RestController;
 
 @RestController
-public class JWTQuiz extends AssignmentEndpoint {
+public class JWTQuiz implements AssignmentEndpoint {
 
   private final String[] solutions = {"Solution 1", "Solution 2"};
   private final boolean[] guesses = new boolean[solutions.length];
diff --git a/src/main/java/org/owasp/webgoat/lessons/jwt/JWTRefreshEndpoint.java b/src/main/java/org/owasp/webgoat/lessons/jwt/JWTRefreshEndpoint.java
index 2f114b04b..03691dee1 100644
--- a/src/main/java/org/owasp/webgoat/lessons/jwt/JWTRefreshEndpoint.java
+++ b/src/main/java/org/owasp/webgoat/lessons/jwt/JWTRefreshEndpoint.java
@@ -58,7 +58,7 @@ import org.springframework.web.bind.annotation.RestController;
   "jwt-refresh-hint3",
   "jwt-refresh-hint4"
 })
-public class JWTRefreshEndpoint extends AssignmentEndpoint {
+public class JWTRefreshEndpoint implements AssignmentEndpoint {
 
   public static final String PASSWORD = "bm5nhSkxCXZkKRy4";
   private static final String JWT_PASSWORD = "bm5n3SkxCX4kKRy4";
diff --git a/src/main/java/org/owasp/webgoat/lessons/jwt/JWTSecretKeyEndpoint.java b/src/main/java/org/owasp/webgoat/lessons/jwt/JWTSecretKeyEndpoint.java
index 595026474..4eb46d6e7 100644
--- a/src/main/java/org/owasp/webgoat/lessons/jwt/JWTSecretKeyEndpoint.java
+++ b/src/main/java/org/owasp/webgoat/lessons/jwt/JWTSecretKeyEndpoint.java
@@ -47,7 +47,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 @RestController
 @AssignmentHints({"jwt-secret-hint1", "jwt-secret-hint2", "jwt-secret-hint3"})
-public class JWTSecretKeyEndpoint extends AssignmentEndpoint {
+public class JWTSecretKeyEndpoint implements AssignmentEndpoint {
 
   public static final String[] SECRETS = {
     "victory", "business", "available", "shipping", "washington"
diff --git a/src/main/java/org/owasp/webgoat/lessons/jwt/JWTVotesEndpoint.java b/src/main/java/org/owasp/webgoat/lessons/jwt/JWTVotesEndpoint.java
index ec69ad3e4..4b4d6486e 100644
--- a/src/main/java/org/owasp/webgoat/lessons/jwt/JWTVotesEndpoint.java
+++ b/src/main/java/org/owasp/webgoat/lessons/jwt/JWTVotesEndpoint.java
@@ -68,7 +68,7 @@ import org.springframework.web.bind.annotation.RestController;
   "jwt-change-token-hint4",
   "jwt-change-token-hint5"
 })
-public class JWTVotesEndpoint extends AssignmentEndpoint {
+public class JWTVotesEndpoint implements AssignmentEndpoint {
 
   public static final String JWT_PASSWORD = TextCodec.BASE64.encode("victory");
   private static String validUsers = "TomJerrySylvester";
diff --git a/src/main/java/org/owasp/webgoat/lessons/jwt/claimmisuse/JWTHeaderJKUEndpoint.java b/src/main/java/org/owasp/webgoat/lessons/jwt/claimmisuse/JWTHeaderJKUEndpoint.java
index 9d85cf960..4ff2e13ca 100644
--- a/src/main/java/org/owasp/webgoat/lessons/jwt/claimmisuse/JWTHeaderJKUEndpoint.java
+++ b/src/main/java/org/owasp/webgoat/lessons/jwt/claimmisuse/JWTHeaderJKUEndpoint.java
@@ -31,7 +31,7 @@ import org.springframework.web.bind.annotation.RestController;
   "jwt-jku-hint4",
   "jwt-jku-hint5"
 })
-public class JWTHeaderJKUEndpoint extends AssignmentEndpoint {
+public class JWTHeaderJKUEndpoint implements AssignmentEndpoint {
 
   @PostMapping("jku/follow/{user}")
   public @ResponseBody String follow(@PathVariable("user") String user) {
diff --git a/src/main/java/org/owasp/webgoat/lessons/jwt/claimmisuse/JWTHeaderKIDEndpoint.java b/src/main/java/org/owasp/webgoat/lessons/jwt/claimmisuse/JWTHeaderKIDEndpoint.java
index 41909057d..904f2656f 100644
--- a/src/main/java/org/owasp/webgoat/lessons/jwt/claimmisuse/JWTHeaderKIDEndpoint.java
+++ b/src/main/java/org/owasp/webgoat/lessons/jwt/claimmisuse/JWTHeaderKIDEndpoint.java
@@ -56,7 +56,7 @@ import org.springframework.web.bind.annotation.RestController;
   "jwt-kid-hint6"
 })
 @RequestMapping("/JWT/")
-public class JWTHeaderKIDEndpoint extends AssignmentEndpoint {
+public class JWTHeaderKIDEndpoint implements AssignmentEndpoint {
   private final LessonDataSource dataSource;
 
   private JWTHeaderKIDEndpoint(LessonDataSource dataSource) {
diff --git a/src/main/java/org/owasp/webgoat/lessons/lessontemplate/SampleAttack.java b/src/main/java/org/owasp/webgoat/lessons/lessontemplate/SampleAttack.java
index 7015888ca..d4f0c1b86 100644
--- a/src/main/java/org/owasp/webgoat/lessons/lessontemplate/SampleAttack.java
+++ b/src/main/java/org/owasp/webgoat/lessons/lessontemplate/SampleAttack.java
@@ -41,7 +41,7 @@ import org.springframework.web.bind.annotation.RestController;
 /** Created by jason on 1/5/17. */
 @RestController
 @AssignmentHints({"lesson-template.hints.1", "lesson-template.hints.2", "lesson-template.hints.3"})
-public class SampleAttack extends AssignmentEndpoint {
+public class SampleAttack implements AssignmentEndpoint {
   private static final String secretValue = "secr37Value";
 
   private final LessonSession userSessionData;
diff --git a/src/main/java/org/owasp/webgoat/lessons/logging/LogBleedingTask.java b/src/main/java/org/owasp/webgoat/lessons/logging/LogBleedingTask.java
index 5eee7b450..7b1f68937 100644
--- a/src/main/java/org/owasp/webgoat/lessons/logging/LogBleedingTask.java
+++ b/src/main/java/org/owasp/webgoat/lessons/logging/LogBleedingTask.java
@@ -39,7 +39,7 @@ import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.bind.annotation.RestController;
 
 @RestController
-public class LogBleedingTask extends AssignmentEndpoint {
+public class LogBleedingTask implements AssignmentEndpoint {
 
   private static final Logger log = LoggerFactory.getLogger(LogBleedingTask.class);
   private final String password;
diff --git a/src/main/java/org/owasp/webgoat/lessons/logging/LogSpoofingTask.java b/src/main/java/org/owasp/webgoat/lessons/logging/LogSpoofingTask.java
index b88abf073..bcce8a57a 100644
--- a/src/main/java/org/owasp/webgoat/lessons/logging/LogSpoofingTask.java
+++ b/src/main/java/org/owasp/webgoat/lessons/logging/LogSpoofingTask.java
@@ -34,7 +34,7 @@ import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.bind.annotation.RestController;
 
 @RestController
-public class LogSpoofingTask extends AssignmentEndpoint {
+public class LogSpoofingTask implements AssignmentEndpoint {
 
   @PostMapping("/LogSpoofing/log-spoofing")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/missingac/MissingFunctionACHiddenMenus.java b/src/main/java/org/owasp/webgoat/lessons/missingac/MissingFunctionACHiddenMenus.java
index 1ef798fe2..2bbb06687 100644
--- a/src/main/java/org/owasp/webgoat/lessons/missingac/MissingFunctionACHiddenMenus.java
+++ b/src/main/java/org/owasp/webgoat/lessons/missingac/MissingFunctionACHiddenMenus.java
@@ -39,7 +39,7 @@ import org.springframework.web.bind.annotation.RestController;
   "access-control.hidden-menus.hint2",
   "access-control.hidden-menus.hint3"
 })
-public class MissingFunctionACHiddenMenus extends AssignmentEndpoint {
+public class MissingFunctionACHiddenMenus implements AssignmentEndpoint {
 
   @PostMapping(
       path = "/access-control/hidden-menu",
diff --git a/src/main/java/org/owasp/webgoat/lessons/missingac/MissingFunctionACYourHash.java b/src/main/java/org/owasp/webgoat/lessons/missingac/MissingFunctionACYourHash.java
index 28eb11cf6..722e376f9 100644
--- a/src/main/java/org/owasp/webgoat/lessons/missingac/MissingFunctionACYourHash.java
+++ b/src/main/java/org/owasp/webgoat/lessons/missingac/MissingFunctionACYourHash.java
@@ -41,7 +41,7 @@ import org.springframework.web.bind.annotation.RestController;
   "access-control.hash.hint4",
   "access-control.hash.hint5"
 })
-public class MissingFunctionACYourHash extends AssignmentEndpoint {
+public class MissingFunctionACYourHash implements AssignmentEndpoint {
 
   private final MissingAccessControlUserRepository userRepository;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/missingac/MissingFunctionACYourHashAdmin.java b/src/main/java/org/owasp/webgoat/lessons/missingac/MissingFunctionACYourHashAdmin.java
index 3027b860b..c36442a2a 100644
--- a/src/main/java/org/owasp/webgoat/lessons/missingac/MissingFunctionACYourHashAdmin.java
+++ b/src/main/java/org/owasp/webgoat/lessons/missingac/MissingFunctionACYourHashAdmin.java
@@ -44,7 +44,7 @@ import org.springframework.web.bind.annotation.RestController;
   "access-control.hash.hint12",
   "access-control.hash.hint13"
 })
-public class MissingFunctionACYourHashAdmin extends AssignmentEndpoint {
+public class MissingFunctionACYourHashAdmin implements AssignmentEndpoint {
 
   private final MissingAccessControlUserRepository userRepository;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/passwordreset/QuestionsAssignment.java b/src/main/java/org/owasp/webgoat/lessons/passwordreset/QuestionsAssignment.java
index 9e441a7de..02a9475da 100644
--- a/src/main/java/org/owasp/webgoat/lessons/passwordreset/QuestionsAssignment.java
+++ b/src/main/java/org/owasp/webgoat/lessons/passwordreset/QuestionsAssignment.java
@@ -40,7 +40,7 @@ import org.springframework.web.bind.annotation.RestController;
  * @since 8/20/17.
  */
 @RestController
-public class QuestionsAssignment extends AssignmentEndpoint {
+public class QuestionsAssignment implements AssignmentEndpoint {
 
   private static final Map<String, String> COLORS = new HashMap<>();
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/passwordreset/ResetLinkAssignment.java b/src/main/java/org/owasp/webgoat/lessons/passwordreset/ResetLinkAssignment.java
index 8b6c18908..3fe8af534 100644
--- a/src/main/java/org/owasp/webgoat/lessons/passwordreset/ResetLinkAssignment.java
+++ b/src/main/java/org/owasp/webgoat/lessons/passwordreset/ResetLinkAssignment.java
@@ -60,7 +60,7 @@ import org.springframework.web.servlet.ModelAndView;
   "password-reset-hint5",
   "password-reset-hint6"
 })
-public class ResetLinkAssignment extends AssignmentEndpoint {
+public class ResetLinkAssignment implements AssignmentEndpoint {
 
   private static final String VIEW_FORMATTER = "lessons/passwordreset/templates/%s.html";
   static final String PASSWORD_TOM_9 =
diff --git a/src/main/java/org/owasp/webgoat/lessons/passwordreset/ResetLinkAssignmentForgotPassword.java b/src/main/java/org/owasp/webgoat/lessons/passwordreset/ResetLinkAssignmentForgotPassword.java
index 5fe6cd84d..1a2780467 100644
--- a/src/main/java/org/owasp/webgoat/lessons/passwordreset/ResetLinkAssignmentForgotPassword.java
+++ b/src/main/java/org/owasp/webgoat/lessons/passwordreset/ResetLinkAssignmentForgotPassword.java
@@ -47,7 +47,7 @@ import org.springframework.web.client.RestTemplate;
  * @since 8/20/17.
  */
 @RestController
-public class ResetLinkAssignmentForgotPassword extends AssignmentEndpoint {
+public class ResetLinkAssignmentForgotPassword implements AssignmentEndpoint {
 
   private final RestTemplate restTemplate;
   private final String webWolfHost;
diff --git a/src/main/java/org/owasp/webgoat/lessons/passwordreset/SecurityQuestionAssignment.java b/src/main/java/org/owasp/webgoat/lessons/passwordreset/SecurityQuestionAssignment.java
index 63d17ea1f..f08bc7890 100644
--- a/src/main/java/org/owasp/webgoat/lessons/passwordreset/SecurityQuestionAssignment.java
+++ b/src/main/java/org/owasp/webgoat/lessons/passwordreset/SecurityQuestionAssignment.java
@@ -42,7 +42,7 @@ import org.springframework.web.bind.annotation.RestController;
  * @since 11.12.18
  */
 @RestController
-public class SecurityQuestionAssignment extends AssignmentEndpoint {
+public class SecurityQuestionAssignment implements AssignmentEndpoint {
 
   private final TriedQuestions triedQuestions;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/passwordreset/SimpleMailAssignment.java b/src/main/java/org/owasp/webgoat/lessons/passwordreset/SimpleMailAssignment.java
index 32554f417..cd862d49b 100644
--- a/src/main/java/org/owasp/webgoat/lessons/passwordreset/SimpleMailAssignment.java
+++ b/src/main/java/org/owasp/webgoat/lessons/passwordreset/SimpleMailAssignment.java
@@ -46,7 +46,7 @@ import org.springframework.web.client.RestTemplate;
  * @since 8/20/17.
  */
 @RestController
-public class SimpleMailAssignment extends AssignmentEndpoint {
+public class SimpleMailAssignment implements AssignmentEndpoint {
   private final String webWolfURL;
   private RestTemplate restTemplate;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/pathtraversal/ProfileUploadBase.java b/src/main/java/org/owasp/webgoat/lessons/pathtraversal/ProfileUploadBase.java
index 78662b46e..f212b170e 100644
--- a/src/main/java/org/owasp/webgoat/lessons/pathtraversal/ProfileUploadBase.java
+++ b/src/main/java/org/owasp/webgoat/lessons/pathtraversal/ProfileUploadBase.java
@@ -25,7 +25,7 @@ import org.springframework.util.StringUtils;
 import org.springframework.web.multipart.MultipartFile;
 
 @Getter
-public class ProfileUploadBase extends AssignmentEndpoint {
+public class ProfileUploadBase implements AssignmentEndpoint {
 
   private final String webGoatHomeDirectory;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/pathtraversal/ProfileUploadRetrieval.java b/src/main/java/org/owasp/webgoat/lessons/pathtraversal/ProfileUploadRetrieval.java
index 02674c12b..2225c4d50 100644
--- a/src/main/java/org/owasp/webgoat/lessons/pathtraversal/ProfileUploadRetrieval.java
+++ b/src/main/java/org/owasp/webgoat/lessons/pathtraversal/ProfileUploadRetrieval.java
@@ -43,7 +43,7 @@ import org.springframework.web.bind.annotation.RestController;
   "path-traversal-profile-retrieve.hint6"
 })
 @Slf4j
-public class ProfileUploadRetrieval extends AssignmentEndpoint {
+public class ProfileUploadRetrieval implements AssignmentEndpoint {
   private final File catPicturesDirectory;
 
   public ProfileUploadRetrieval(@Value("${webgoat.server.directory}") String webGoatHomeDirectory) {
diff --git a/src/main/java/org/owasp/webgoat/lessons/securepasswords/SecurePasswordsAssignment.java b/src/main/java/org/owasp/webgoat/lessons/securepasswords/SecurePasswordsAssignment.java
index 3178407d0..b90adf437 100644
--- a/src/main/java/org/owasp/webgoat/lessons/securepasswords/SecurePasswordsAssignment.java
+++ b/src/main/java/org/owasp/webgoat/lessons/securepasswords/SecurePasswordsAssignment.java
@@ -38,7 +38,7 @@ import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.bind.annotation.RestController;
 
 @RestController
-public class SecurePasswordsAssignment extends AssignmentEndpoint {
+public class SecurePasswordsAssignment implements AssignmentEndpoint {
 
   @PostMapping("SecurePasswords/assignment")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/spoofcookie/SpoofCookieAssignment.java b/src/main/java/org/owasp/webgoat/lessons/spoofcookie/SpoofCookieAssignment.java
index 437641fbf..6d68423b8 100644
--- a/src/main/java/org/owasp/webgoat/lessons/spoofcookie/SpoofCookieAssignment.java
+++ b/src/main/java/org/owasp/webgoat/lessons/spoofcookie/SpoofCookieAssignment.java
@@ -52,7 +52,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 @AssignmentHints({"spoofcookie.hint1", "spoofcookie.hint2", "spoofcookie.hint3"})
 @RestController
-public class SpoofCookieAssignment extends AssignmentEndpoint {
+public class SpoofCookieAssignment implements AssignmentEndpoint {
 
   private static final String COOKIE_NAME = "spoof_auth";
   private static final String COOKIE_INFO =
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionChallenge.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionChallenge.java
index 19c0d953b..f5b0a88ba 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionChallenge.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionChallenge.java
@@ -45,7 +45,7 @@ import org.springframework.web.bind.annotation.RestController;
 @AssignmentHints(
     value = {"SqlInjectionChallenge1", "SqlInjectionChallenge2", "SqlInjectionChallenge3"})
 @Slf4j
-public class SqlInjectionChallenge extends AssignmentEndpoint {
+public class SqlInjectionChallenge implements AssignmentEndpoint {
 
   private final LessonDataSource dataSource;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionChallengeLogin.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionChallengeLogin.java
index f071ae6d6..4a6374851 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionChallengeLogin.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionChallengeLogin.java
@@ -42,7 +42,7 @@ import org.springframework.web.bind.annotation.RestController;
       "SqlInjectionChallengeHint3",
       "SqlInjectionChallengeHint4"
     })
-public class SqlInjectionChallengeLogin extends AssignmentEndpoint {
+public class SqlInjectionChallengeLogin implements AssignmentEndpoint {
   private final LessonDataSource dataSource;
 
   public SqlInjectionChallengeLogin(LessonDataSource dataSource) {
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionLesson6a.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionLesson6a.java
index 78c9351dd..96f090ff7 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionLesson6a.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionLesson6a.java
@@ -49,7 +49,7 @@ import org.springframework.web.bind.annotation.RestController;
       "SqlStringInjectionHint-advanced-6a-4",
       "SqlStringInjectionHint-advanced-6a-5"
     })
-public class SqlInjectionLesson6a extends AssignmentEndpoint {
+public class SqlInjectionLesson6a implements AssignmentEndpoint {
   private final LessonDataSource dataSource;
   private static final String YOUR_QUERY_WAS = "<br> Your query was: ";
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionLesson6b.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionLesson6b.java
index 90d19af7f..36e8530ab 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionLesson6b.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionLesson6b.java
@@ -39,7 +39,7 @@ import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.bind.annotation.RestController;
 
 @RestController
-public class SqlInjectionLesson6b extends AssignmentEndpoint {
+public class SqlInjectionLesson6b implements AssignmentEndpoint {
   private final LessonDataSource dataSource;
 
   public SqlInjectionLesson6b(LessonDataSource dataSource) {
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionQuiz.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionQuiz.java
index 2aa031ab2..841bafbbf 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionQuiz.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/advanced/SqlInjectionQuiz.java
@@ -40,7 +40,7 @@ import org.springframework.web.bind.annotation.RestController;
  * implement the quiz go to the quiz.js file in webgoat-container -> js
  */
 @RestController
-public class SqlInjectionQuiz extends AssignmentEndpoint {
+public class SqlInjectionQuiz implements AssignmentEndpoint {
 
   String[] solutions = {"Solution 4", "Solution 3", "Solution 2", "Solution 3", "Solution 4"};
   boolean[] guesses = new boolean[solutions.length];
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson10.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson10.java
index ff141b389..215a00bf3 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson10.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson10.java
@@ -48,7 +48,7 @@ import org.springframework.web.bind.annotation.RestController;
       "SqlStringInjectionHint.10.5",
       "SqlStringInjectionHint.10.6"
     })
-public class SqlInjectionLesson10 extends AssignmentEndpoint {
+public class SqlInjectionLesson10 implements AssignmentEndpoint {
 
   private final LessonDataSource dataSource;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson2.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson2.java
index 6431774d8..15f595960 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson2.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson2.java
@@ -47,7 +47,7 @@ import org.springframework.web.bind.annotation.RestController;
       "SqlStringInjectionHint2-3",
       "SqlStringInjectionHint2-4"
     })
-public class SqlInjectionLesson2 extends AssignmentEndpoint {
+public class SqlInjectionLesson2 implements AssignmentEndpoint {
 
   private final LessonDataSource dataSource;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson3.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson3.java
index 3d562c3bd..352fa5e2c 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson3.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson3.java
@@ -42,7 +42,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 @RestController
 @AssignmentHints(value = {"SqlStringInjectionHint3-1", "SqlStringInjectionHint3-2"})
-public class SqlInjectionLesson3 extends AssignmentEndpoint {
+public class SqlInjectionLesson3 implements AssignmentEndpoint {
 
   private final LessonDataSource dataSource;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson4.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson4.java
index bdb8cf9eb..24a64d287 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson4.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson4.java
@@ -43,7 +43,7 @@ import org.springframework.web.bind.annotation.RestController;
 @RestController
 @AssignmentHints(
     value = {"SqlStringInjectionHint4-1", "SqlStringInjectionHint4-2", "SqlStringInjectionHint4-3"})
-public class SqlInjectionLesson4 extends AssignmentEndpoint {
+public class SqlInjectionLesson4 implements AssignmentEndpoint {
 
   private final LessonDataSource dataSource;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson5.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson5.java
index 289430a2f..aa6e29200 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson5.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson5.java
@@ -46,7 +46,7 @@ import org.springframework.web.bind.annotation.RestController;
       "SqlStringInjectionHint5-3",
       "SqlStringInjectionHint5-4"
     })
-public class SqlInjectionLesson5 extends AssignmentEndpoint {
+public class SqlInjectionLesson5 implements AssignmentEndpoint {
 
   private final LessonDataSource dataSource;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson5a.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson5a.java
index e3a224a91..74431a9bf 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson5a.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson5a.java
@@ -37,7 +37,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 @RestController
 @AssignmentHints(value = {"SqlStringInjectionHint5a1"})
-public class SqlInjectionLesson5a extends AssignmentEndpoint {
+public class SqlInjectionLesson5a implements AssignmentEndpoint {
 
   private static final String EXPLANATION =
       "<br> Explanation: This injection works, because <span style=\"font-style: italic\">or '1' ="
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson5b.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson5b.java
index 85e775a6f..4e4d3c41b 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson5b.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson5b.java
@@ -44,7 +44,7 @@ import org.springframework.web.bind.annotation.RestController;
       "SqlStringInjectionHint5b3",
       "SqlStringInjectionHint5b4"
     })
-public class SqlInjectionLesson5b extends AssignmentEndpoint {
+public class SqlInjectionLesson5b implements AssignmentEndpoint {
 
   private final LessonDataSource dataSource;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson8.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson8.java
index 35ad87eb1..56f81ff56 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson8.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson8.java
@@ -48,7 +48,7 @@ import org.springframework.web.bind.annotation.RestController;
       "SqlStringInjectionHint.8.4",
       "SqlStringInjectionHint.8.5"
     })
-public class SqlInjectionLesson8 extends AssignmentEndpoint {
+public class SqlInjectionLesson8 implements AssignmentEndpoint {
 
   private final LessonDataSource dataSource;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson9.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson9.java
index 4dc1e6a1b..79ec3bb0a 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson9.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/introduction/SqlInjectionLesson9.java
@@ -49,7 +49,7 @@ import org.springframework.web.bind.annotation.RestController;
       "SqlStringInjectionHint.9.4",
       "SqlStringInjectionHint.9.5"
     })
-public class SqlInjectionLesson9 extends AssignmentEndpoint {
+public class SqlInjectionLesson9 implements AssignmentEndpoint {
 
   private final LessonDataSource dataSource;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlInjectionLesson10a.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlInjectionLesson10a.java
index e2e44b95f..d4dc18d2c 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlInjectionLesson10a.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlInjectionLesson10a.java
@@ -38,7 +38,7 @@ import org.springframework.web.bind.annotation.RestController;
 @Slf4j
 @AssignmentHints(
     value = {"SqlStringInjectionHint-mitigation-10a-1", "SqlStringInjectionHint-mitigation-10a-2"})
-public class SqlInjectionLesson10a extends AssignmentEndpoint {
+public class SqlInjectionLesson10a implements AssignmentEndpoint {
 
   private static final String[] results = {
     "getConnection", "PreparedStatement", "prepareStatement", "?", "?", "setString", "setString"
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlInjectionLesson10b.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlInjectionLesson10b.java
index d3c413f5e..2037313f6 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlInjectionLesson10b.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlInjectionLesson10b.java
@@ -55,7 +55,7 @@ import org.springframework.web.bind.annotation.RestController;
       "SqlStringInjectionHint-mitigation-10b-4",
       "SqlStringInjectionHint-mitigation-10b-5"
     })
-public class SqlInjectionLesson10b extends AssignmentEndpoint {
+public class SqlInjectionLesson10b implements AssignmentEndpoint {
 
   @PostMapping("/SqlInjectionMitigations/attack10b")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlInjectionLesson13.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlInjectionLesson13.java
index e9cd2c6fb..f2ac154d0 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlInjectionLesson13.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlInjectionLesson13.java
@@ -48,7 +48,7 @@ import org.springframework.web.bind.annotation.RestController;
       "SqlStringInjectionHint-mitigation-13-4"
     })
 @Slf4j
-public class SqlInjectionLesson13 extends AssignmentEndpoint {
+public class SqlInjectionLesson13 implements AssignmentEndpoint {
 
   private final LessonDataSource dataSource;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlOnlyInputValidation.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlOnlyInputValidation.java
index 2ed20811d..f0df96711 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlOnlyInputValidation.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlOnlyInputValidation.java
@@ -36,7 +36,7 @@ import org.springframework.web.bind.annotation.RestController;
 @RestController
 @AssignmentHints(
     value = {"SqlOnlyInputValidation-1", "SqlOnlyInputValidation-2", "SqlOnlyInputValidation-3"})
-public class SqlOnlyInputValidation extends AssignmentEndpoint {
+public class SqlOnlyInputValidation implements AssignmentEndpoint {
 
   private final SqlInjectionLesson6a lesson6a;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlOnlyInputValidationOnKeywords.java b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlOnlyInputValidationOnKeywords.java
index 55ba0bfd8..0ca75999a 100644
--- a/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlOnlyInputValidationOnKeywords.java
+++ b/src/main/java/org/owasp/webgoat/lessons/sqlinjection/mitigation/SqlOnlyInputValidationOnKeywords.java
@@ -40,7 +40,7 @@ import org.springframework.web.bind.annotation.RestController;
       "SqlOnlyInputValidationOnKeywords-2",
       "SqlOnlyInputValidationOnKeywords-3"
     })
-public class SqlOnlyInputValidationOnKeywords extends AssignmentEndpoint {
+public class SqlOnlyInputValidationOnKeywords implements AssignmentEndpoint {
 
   private final SqlInjectionLesson6a lesson6a;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/ssrf/SSRFTask1.java b/src/main/java/org/owasp/webgoat/lessons/ssrf/SSRFTask1.java
index 27be6645e..986602731 100644
--- a/src/main/java/org/owasp/webgoat/lessons/ssrf/SSRFTask1.java
+++ b/src/main/java/org/owasp/webgoat/lessons/ssrf/SSRFTask1.java
@@ -35,7 +35,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 @RestController
 @AssignmentHints({"ssrf.hint1", "ssrf.hint2"})
-public class SSRFTask1 extends AssignmentEndpoint {
+public class SSRFTask1 implements AssignmentEndpoint {
 
   @PostMapping("/SSRF/task1")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/ssrf/SSRFTask2.java b/src/main/java/org/owasp/webgoat/lessons/ssrf/SSRFTask2.java
index 18afec778..a48b42278 100644
--- a/src/main/java/org/owasp/webgoat/lessons/ssrf/SSRFTask2.java
+++ b/src/main/java/org/owasp/webgoat/lessons/ssrf/SSRFTask2.java
@@ -40,7 +40,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 @RestController
 @AssignmentHints({"ssrf.hint3"})
-public class SSRFTask2 extends AssignmentEndpoint {
+public class SSRFTask2 implements AssignmentEndpoint {
 
   @PostMapping("/SSRF/task2")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/vulnerablecomponents/VulnerableComponentsLesson.java b/src/main/java/org/owasp/webgoat/lessons/vulnerablecomponents/VulnerableComponentsLesson.java
index cdbdbdcd9..e2edd5667 100644
--- a/src/main/java/org/owasp/webgoat/lessons/vulnerablecomponents/VulnerableComponentsLesson.java
+++ b/src/main/java/org/owasp/webgoat/lessons/vulnerablecomponents/VulnerableComponentsLesson.java
@@ -37,7 +37,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 @RestController
 @AssignmentHints({"vulnerable.hint"})
-public class VulnerableComponentsLesson extends AssignmentEndpoint {
+public class VulnerableComponentsLesson implements AssignmentEndpoint {
 
   @PostMapping("/VulnerableComponents/attack1")
   public @ResponseBody AttackResult completed(@RequestParam String payload) {
diff --git a/src/main/java/org/owasp/webgoat/lessons/webwolfintroduction/LandingAssignment.java b/src/main/java/org/owasp/webgoat/lessons/webwolfintroduction/LandingAssignment.java
index 954a3f8f8..152bae920 100644
--- a/src/main/java/org/owasp/webgoat/lessons/webwolfintroduction/LandingAssignment.java
+++ b/src/main/java/org/owasp/webgoat/lessons/webwolfintroduction/LandingAssignment.java
@@ -41,7 +41,7 @@ import org.springframework.web.servlet.ModelAndView;
  * @since 8/20/17.
  */
 @RestController
-public class LandingAssignment extends AssignmentEndpoint {
+public class LandingAssignment implements AssignmentEndpoint {
   private final String landingPageUrl;
 
   public LandingAssignment(@Value("${webwolf.landingpage.url}") String landingPageUrl) {
diff --git a/src/main/java/org/owasp/webgoat/lessons/webwolfintroduction/MailAssignment.java b/src/main/java/org/owasp/webgoat/lessons/webwolfintroduction/MailAssignment.java
index 12d969764..274887640 100644
--- a/src/main/java/org/owasp/webgoat/lessons/webwolfintroduction/MailAssignment.java
+++ b/src/main/java/org/owasp/webgoat/lessons/webwolfintroduction/MailAssignment.java
@@ -43,7 +43,7 @@ import org.springframework.web.client.RestTemplate;
  * @since 8/20/17.
  */
 @RestController
-public class MailAssignment extends AssignmentEndpoint {
+public class MailAssignment implements AssignmentEndpoint {
 
   private final String webWolfURL;
   private RestTemplate restTemplate;
diff --git a/src/main/java/org/owasp/webgoat/lessons/xss/CrossSiteScriptingLesson1.java b/src/main/java/org/owasp/webgoat/lessons/xss/CrossSiteScriptingLesson1.java
index 3d5495e70..79ee3469e 100644
--- a/src/main/java/org/owasp/webgoat/lessons/xss/CrossSiteScriptingLesson1.java
+++ b/src/main/java/org/owasp/webgoat/lessons/xss/CrossSiteScriptingLesson1.java
@@ -33,7 +33,7 @@ import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.bind.annotation.RestController;
 
 @RestController
-public class CrossSiteScriptingLesson1 extends AssignmentEndpoint {
+public class CrossSiteScriptingLesson1 implements AssignmentEndpoint {
 
   @PostMapping("/CrossSiteScripting/attack1")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/xss/CrossSiteScriptingLesson5a.java b/src/main/java/org/owasp/webgoat/lessons/xss/CrossSiteScriptingLesson5a.java
index aebf897cb..dcc1b5903 100644
--- a/src/main/java/org/owasp/webgoat/lessons/xss/CrossSiteScriptingLesson5a.java
+++ b/src/main/java/org/owasp/webgoat/lessons/xss/CrossSiteScriptingLesson5a.java
@@ -44,7 +44,7 @@ import org.springframework.web.bind.annotation.RestController;
       "xss-reflected-5a-hint-3",
       "xss-reflected-5a-hint-4"
     })
-public class CrossSiteScriptingLesson5a extends AssignmentEndpoint {
+public class CrossSiteScriptingLesson5a implements AssignmentEndpoint {
 
   public static final Predicate<String> XSS_PATTERN =
       Pattern.compile(
diff --git a/src/main/java/org/owasp/webgoat/lessons/xss/CrossSiteScriptingLesson6a.java b/src/main/java/org/owasp/webgoat/lessons/xss/CrossSiteScriptingLesson6a.java
index b3dcd86a9..a6fb245c3 100644
--- a/src/main/java/org/owasp/webgoat/lessons/xss/CrossSiteScriptingLesson6a.java
+++ b/src/main/java/org/owasp/webgoat/lessons/xss/CrossSiteScriptingLesson6a.java
@@ -42,7 +42,7 @@ import org.springframework.web.bind.annotation.RestController;
       "xss-reflected-6a-hint-3",
       "xss-reflected-6a-hint-4"
     })
-public class CrossSiteScriptingLesson6a extends AssignmentEndpoint {
+public class CrossSiteScriptingLesson6a implements AssignmentEndpoint {
   private final LessonSession userSessionData;
 
   public CrossSiteScriptingLesson6a(LessonSession userSessionData) {
diff --git a/src/main/java/org/owasp/webgoat/lessons/xss/CrossSiteScriptingQuiz.java b/src/main/java/org/owasp/webgoat/lessons/xss/CrossSiteScriptingQuiz.java
index a83a73667..ab2a0a310 100644
--- a/src/main/java/org/owasp/webgoat/lessons/xss/CrossSiteScriptingQuiz.java
+++ b/src/main/java/org/owasp/webgoat/lessons/xss/CrossSiteScriptingQuiz.java
@@ -35,7 +35,7 @@ import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.bind.annotation.RestController;
 
 @RestController
-public class CrossSiteScriptingQuiz extends AssignmentEndpoint {
+public class CrossSiteScriptingQuiz implements AssignmentEndpoint {
 
   private static final String[] solutions = {
     "Solution 4", "Solution 3", "Solution 1", "Solution 2", "Solution 4"
diff --git a/src/main/java/org/owasp/webgoat/lessons/xss/DOMCrossSiteScripting.java b/src/main/java/org/owasp/webgoat/lessons/xss/DOMCrossSiteScripting.java
index 0c1471ada..83b927649 100644
--- a/src/main/java/org/owasp/webgoat/lessons/xss/DOMCrossSiteScripting.java
+++ b/src/main/java/org/owasp/webgoat/lessons/xss/DOMCrossSiteScripting.java
@@ -36,7 +36,7 @@ import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.bind.annotation.RestController;
 
 @RestController
-public class DOMCrossSiteScripting extends AssignmentEndpoint {
+public class DOMCrossSiteScripting implements AssignmentEndpoint {
 
   private final LessonSession lessonSession;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/xss/DOMCrossSiteScriptingVerifier.java b/src/main/java/org/owasp/webgoat/lessons/xss/DOMCrossSiteScriptingVerifier.java
index f8c0df318..87a4e74f6 100644
--- a/src/main/java/org/owasp/webgoat/lessons/xss/DOMCrossSiteScriptingVerifier.java
+++ b/src/main/java/org/owasp/webgoat/lessons/xss/DOMCrossSiteScriptingVerifier.java
@@ -45,7 +45,7 @@ import org.springframework.web.bind.annotation.RestController;
       "xss-dom-message-hint-5",
       "xss-dom-message-hint-6"
     })
-public class DOMCrossSiteScriptingVerifier extends AssignmentEndpoint {
+public class DOMCrossSiteScriptingVerifier implements AssignmentEndpoint {
 
   private final LessonSession lessonSession;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/xss/mitigation/CrossSiteScriptingLesson3.java b/src/main/java/org/owasp/webgoat/lessons/xss/mitigation/CrossSiteScriptingLesson3.java
index e192d1153..dc59d0cb3 100644
--- a/src/main/java/org/owasp/webgoat/lessons/xss/mitigation/CrossSiteScriptingLesson3.java
+++ b/src/main/java/org/owasp/webgoat/lessons/xss/mitigation/CrossSiteScriptingLesson3.java
@@ -44,7 +44,7 @@ import org.springframework.web.bind.annotation.RestController;
       "xss-mitigation-3-hint3",
       "xss-mitigation-3-hint4"
     })
-public class CrossSiteScriptingLesson3 extends AssignmentEndpoint {
+public class CrossSiteScriptingLesson3 implements AssignmentEndpoint {
 
   @PostMapping("/CrossSiteScripting/attack3")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/xss/mitigation/CrossSiteScriptingLesson4.java b/src/main/java/org/owasp/webgoat/lessons/xss/mitigation/CrossSiteScriptingLesson4.java
index ac0e4e34e..7afcc5d27 100644
--- a/src/main/java/org/owasp/webgoat/lessons/xss/mitigation/CrossSiteScriptingLesson4.java
+++ b/src/main/java/org/owasp/webgoat/lessons/xss/mitigation/CrossSiteScriptingLesson4.java
@@ -35,7 +35,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 @RestController
 @AssignmentHints(value = {"xss-mitigation-4-hint1"})
-public class CrossSiteScriptingLesson4 extends AssignmentEndpoint {
+public class CrossSiteScriptingLesson4 implements AssignmentEndpoint {
 
   @PostMapping("/CrossSiteScripting/attack4")
   @ResponseBody
diff --git a/src/main/java/org/owasp/webgoat/lessons/xss/stored/StoredCrossSiteScriptingVerifier.java b/src/main/java/org/owasp/webgoat/lessons/xss/stored/StoredCrossSiteScriptingVerifier.java
index 8deb210f0..6a51ab079 100644
--- a/src/main/java/org/owasp/webgoat/lessons/xss/stored/StoredCrossSiteScriptingVerifier.java
+++ b/src/main/java/org/owasp/webgoat/lessons/xss/stored/StoredCrossSiteScriptingVerifier.java
@@ -35,7 +35,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 /** Created by jason on 11/23/16. */
 @RestController
-public class StoredCrossSiteScriptingVerifier extends AssignmentEndpoint {
+public class StoredCrossSiteScriptingVerifier implements AssignmentEndpoint {
 
   private final LessonSession lessonSession;
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/xss/stored/StoredXssComments.java b/src/main/java/org/owasp/webgoat/lessons/xss/stored/StoredXssComments.java
index d02c86589..7d9c28fbc 100644
--- a/src/main/java/org/owasp/webgoat/lessons/xss/stored/StoredXssComments.java
+++ b/src/main/java/org/owasp/webgoat/lessons/xss/stored/StoredXssComments.java
@@ -49,7 +49,7 @@ import org.springframework.web.bind.annotation.ResponseBody;
 import org.springframework.web.bind.annotation.RestController;
 
 @RestController
-public class StoredXssComments extends AssignmentEndpoint {
+public class StoredXssComments implements AssignmentEndpoint {
 
   private static final DateTimeFormatter fmt = DateTimeFormatter.ofPattern("yyyy-MM-dd, HH:mm:ss");
 
diff --git a/src/main/java/org/owasp/webgoat/lessons/xxe/BlindSendFileAssignment.java b/src/main/java/org/owasp/webgoat/lessons/xxe/BlindSendFileAssignment.java
index 748c43996..55b577259 100644
--- a/src/main/java/org/owasp/webgoat/lessons/xxe/BlindSendFileAssignment.java
+++ b/src/main/java/org/owasp/webgoat/lessons/xxe/BlindSendFileAssignment.java
@@ -60,7 +60,7 @@ import org.springframework.web.bind.annotation.RestController;
   "xxe.blind.hints.4",
   "xxe.blind.hints.5"
 })
-public class BlindSendFileAssignment extends AssignmentEndpoint implements Initializable {
+public class BlindSendFileAssignment implements AssignmentEndpoint, Initializable {
 
   private final String webGoatHomeDirectory;
   private final CommentsCache comments;
diff --git a/src/main/java/org/owasp/webgoat/lessons/xxe/ContentTypeAssignment.java b/src/main/java/org/owasp/webgoat/lessons/xxe/ContentTypeAssignment.java
index 0214eb0c8..4f5ed172e 100644
--- a/src/main/java/org/owasp/webgoat/lessons/xxe/ContentTypeAssignment.java
+++ b/src/main/java/org/owasp/webgoat/lessons/xxe/ContentTypeAssignment.java
@@ -47,7 +47,7 @@ import org.springframework.web.bind.annotation.RestController;
 
 @RestController
 @AssignmentHints({"xxe.hints.content.type.xxe.1", "xxe.hints.content.type.xxe.2"})
-public class ContentTypeAssignment extends AssignmentEndpoint {
+public class ContentTypeAssignment implements AssignmentEndpoint {
 
   private static final String[] DEFAULT_LINUX_DIRECTORIES = {"usr", "etc", "var"};
   private static final String[] DEFAULT_WINDOWS_DIRECTORIES = {
diff --git a/src/main/java/org/owasp/webgoat/lessons/xxe/SimpleXXE.java b/src/main/java/org/owasp/webgoat/lessons/xxe/SimpleXXE.java
index ecf7698e3..2547cbcd4 100644
--- a/src/main/java/org/owasp/webgoat/lessons/xxe/SimpleXXE.java
+++ b/src/main/java/org/owasp/webgoat/lessons/xxe/SimpleXXE.java
@@ -50,7 +50,7 @@ import org.springframework.web.bind.annotation.RestController;
   "xxe.hints.simple.xxe.5",
   "xxe.hints.simple.xxe.6"
 })
-public class SimpleXXE extends AssignmentEndpoint {
+public class SimpleXXE implements AssignmentEndpoint {
 
   private static final String[] DEFAULT_LINUX_DIRECTORIES = {"usr", "etc", "var"};
   private static final String[] DEFAULT_WINDOWS_DIRECTORIES = {
diff --git a/src/main/resources/lessons/lessontemplate/documentation/lesson-template-attack.adoc b/src/main/resources/lessons/lessontemplate/documentation/lesson-template-attack.adoc
index f7c9b9a2e..c40a8f4bb 100644
--- a/src/main/resources/lessons/lessontemplate/documentation/lesson-template-attack.adoc
+++ b/src/main/resources/lessons/lessontemplate/documentation/lesson-template-attack.adoc
@@ -1,13 +1,13 @@
 === Step 4: Add an assignment to your lesson
 
 With an assignment, a user can practice within a lesson. A lesson can consist of multiple assignments, each assignment
-needs to extend the class `AssignmentEndpoint`, let's look at an example:
+needs to implement the class `AssignmentEndpoint`, let's look at an example:
 
 [source,java]
 ----
-@RestController // <1>
+import org.owasp.webgoat.container.assignments.AssignmentEndpoint;@RestController // <1>
 @AssignmentHints({"lesson-template.hints.1", "lesson-template.hints.2", "lesson-template.hints.3"}) // <2>
-public class SampleAttack extends AssignmentEndpoint { // <3>
+public class SampleAttack implements AssignmentEndpoint { // <3>
 
     private final String secretValue = "secr37Value";
 
@@ -32,7 +32,7 @@ public class SampleAttack extends AssignmentEndpoint { // <3>
         }
 
         // else
-        return builder.failed(this) // <8>
+        return failed(this) // <8>
                 .feedback("lesson-template.sample-attack.failure-2")
                 .output("Custom output for this failure scenario, usually html that will get rendered directly ... yes, you can self-xss if you want")
                 .build();
@@ -40,7 +40,7 @@ public class SampleAttack extends AssignmentEndpoint { // <3>
 ----
 <1> Every assignment is just a Spring RestController
 <2> Each assignment can have a list of hints. The actual text needs to be placed in `WebGoatLabels.properties` in the folder `src/main/resources/{lessonName}/i18n`
-<3> Each assignment needs to extend the class `AssignmentEndpoint`, giving you some helpful methods you need when you want to mark an assignment as complete
+<3> Each assignment needs to implement the interface `AssignmentEndpoint`. This is a marker interface, so no methods need to be implemented
 <4> As the assignment is a Spring-based class, you can auto wire every component managed by Spring necessary for the assignment
 <5> Each assignment should at least have one mapping with the method signature (see 6)
 <6> When the user tries to solve an assignment, you need return an `AttackResult`