diff --git a/src/main/java/mops/gruppen2/domain/event/AddUserEvent.java b/src/main/java/mops/gruppen2/domain/event/AddUserEvent.java
index 69d1443..ce2d766 100644
--- a/src/main/java/mops/gruppen2/domain/event/AddUserEvent.java
+++ b/src/main/java/mops/gruppen2/domain/event/AddUserEvent.java
@@ -1,5 +1,7 @@
 package mops.gruppen2.domain.event;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
+import lombok.AllArgsConstructor;
 import lombok.Value;
 import lombok.extern.log4j.Log4j2;
 import mops.gruppen2.domain.exception.EventException;
@@ -14,14 +16,20 @@ import mops.gruppen2.domain.model.User;
 
 @Log4j2
 @Value
+@AllArgsConstructor
 public class AddUserEvent extends Event {
 
+    @JsonProperty("givenname")
     String givenname;
+
+    @JsonProperty("familyname")
     String familyname;
+
+    @JsonProperty("email")
     String email;
 
     public AddUserEvent(Group group, User user) {
-        super(group.getId(), user.getId());
+        super(group.getGroupid(), user.getUserid());
         givenname = user.getGivenname();
         familyname = user.getFamilyname();
         email = user.getEmail();
@@ -29,11 +37,11 @@ public class AddUserEvent extends Event {
 
     @Override
     protected void applyEvent(Group group) throws EventException {
-        ValidationHelper.throwIfMember(group, new User(userId));
+        ValidationHelper.throwIfMember(group, new User(userid));
         ValidationHelper.throwIfGroupFull(group);
 
-        group.getMembers().put(userId, new User(userId, givenname, familyname, email));
-        group.getRoles().put(userId, Role.MEMBER);
+        group.getMembers().put(userid, new User(userid, givenname, familyname, email));
+        group.getRoles().put(userid, Role.MEMBER);
 
         log.trace("\t\t\t\t\tNeue Members: {}", group.getMembers());
         log.trace("\t\t\t\t\tNeue Rollen: {}", group.getRoles());
diff --git a/src/main/java/mops/gruppen2/domain/event/CreateGroupEvent.java b/src/main/java/mops/gruppen2/domain/event/CreateGroupEvent.java
index dbfb695..ac381d9 100644
--- a/src/main/java/mops/gruppen2/domain/event/CreateGroupEvent.java
+++ b/src/main/java/mops/gruppen2/domain/event/CreateGroupEvent.java
@@ -1,29 +1,36 @@
 package mops.gruppen2.domain.event;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
+import lombok.AllArgsConstructor;
 import lombok.Value;
 import lombok.extern.log4j.Log4j2;
 import mops.gruppen2.domain.model.Group;
 import mops.gruppen2.domain.model.Type;
+import mops.gruppen2.domain.model.User;
 
 import java.util.UUID;
 
 @Log4j2
 @Value
+@AllArgsConstructor// Value generiert den allArgsConstrucot nur, wenn keiner explizit angegeben ist
 public class CreateGroupEvent extends Event {
 
-    UUID groupParent;
+    @JsonProperty("parent")
+    UUID parent;
+
+    @JsonProperty("type")
     Type type;
 
-    public CreateGroupEvent(UUID groupId, String userId, UUID parent, Type type) {
-        super(groupId, userId);
-        groupParent = parent;
+    public CreateGroupEvent(UUID groupId, User user, UUID parent, Type type) {
+        super(groupId, user.getUserid());
+        this.parent = parent;
         this.type = type;
     }
 
     @Override
     protected void applyEvent(Group group) {
-        group.setId(groupId);
-        group.setParent(groupParent);
+        group.setGroupid(groupid);
+        group.setParent(parent);
         group.setType(type);
 
         log.trace("\t\t\t\t\tNeue Gruppe: {}", group.toString());
diff --git a/src/main/java/mops/gruppen2/domain/event/DeleteGroupEvent.java b/src/main/java/mops/gruppen2/domain/event/DeleteGroupEvent.java
index 0b62ad7..a2f79be 100644
--- a/src/main/java/mops/gruppen2/domain/event/DeleteGroupEvent.java
+++ b/src/main/java/mops/gruppen2/domain/event/DeleteGroupEvent.java
@@ -1,5 +1,6 @@
 package mops.gruppen2.domain.event;
 
+import lombok.AllArgsConstructor;
 import lombok.Value;
 import lombok.extern.log4j.Log4j2;
 import mops.gruppen2.domain.model.Group;
@@ -7,10 +8,11 @@ import mops.gruppen2.domain.model.User;
 
 @Log4j2
 @Value
+@AllArgsConstructor
 public class DeleteGroupEvent extends Event {
 
     public DeleteGroupEvent(Group group, User user) {
-        super(group.getId(), user.getId());
+        super(group.getGroupid(), user.getUserid());
     }
 
     @Override
@@ -21,7 +23,7 @@ public class DeleteGroupEvent extends Event {
         group.setDescription(null);
         group.setType(null);
         group.setParent(null);
-        group.setUserLimit(null);
+        group.setLimit(null);
 
         log.trace("\t\t\t\t\tGelöschte Gruppe: {}", group);
     }
diff --git a/src/main/java/mops/gruppen2/domain/event/DeleteUserEvent.java b/src/main/java/mops/gruppen2/domain/event/DeleteUserEvent.java
index 12ba916..eb7d3fe 100644
--- a/src/main/java/mops/gruppen2/domain/event/DeleteUserEvent.java
+++ b/src/main/java/mops/gruppen2/domain/event/DeleteUserEvent.java
@@ -1,5 +1,6 @@
 package mops.gruppen2.domain.event;
 
+import lombok.AllArgsConstructor;
 import lombok.Value;
 import lombok.extern.log4j.Log4j2;
 import mops.gruppen2.domain.exception.EventException;
@@ -12,18 +13,19 @@ import mops.gruppen2.domain.model.User;
  */
 @Log4j2
 @Value
+@AllArgsConstructor
 public class DeleteUserEvent extends Event {
 
     public DeleteUserEvent(Group group, User user) {
-        super(group.getId(), user.getId());
+        super(group.getGroupid(), user.getUserid());
     }
 
     @Override
     protected void applyEvent(Group group) throws EventException {
-        ValidationHelper.throwIfNoMember(group, new User(userId));
+        ValidationHelper.throwIfNoMember(group, new User(userid));
 
-        group.getMembers().remove(userId);
-        group.getRoles().remove(userId);
+        group.getMembers().remove(userid);
+        group.getRoles().remove(userid);
 
         log.trace("\t\t\t\t\tNeue Members: {}", group.getMembers());
         log.trace("\t\t\t\t\tNeue Rollen: {}", group.getRoles());
diff --git a/src/main/java/mops/gruppen2/domain/event/Event.java b/src/main/java/mops/gruppen2/domain/event/Event.java
index a83f2ab..3fbf498 100644
--- a/src/main/java/mops/gruppen2/domain/event/Event.java
+++ b/src/main/java/mops/gruppen2/domain/event/Event.java
@@ -1,5 +1,6 @@
 package mops.gruppen2.domain.event;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.annotation.JsonSubTypes;
 import com.fasterxml.jackson.annotation.JsonTypeInfo;
 import lombok.AllArgsConstructor;
@@ -12,32 +13,29 @@ import mops.gruppen2.domain.model.Group;
 
 import java.util.UUID;
 
-
 @Log4j2
-@JsonTypeInfo(
-        use = JsonTypeInfo.Id.NAME,
-        property = "type"
-)
-@JsonSubTypes({
-                      @JsonSubTypes.Type(value = AddUserEvent.class, name = "AddUserEvent"),
-                      @JsonSubTypes.Type(value = CreateGroupEvent.class, name = "CreateGroupEvent"),
-                      @JsonSubTypes.Type(value = DeleteUserEvent.class, name = "DeleteUserEvent"),
-                      @JsonSubTypes.Type(value = UpdateGroupDescriptionEvent.class, name = "UpdateGroupDescriptionEvent"),
-                      @JsonSubTypes.Type(value = UpdateGroupTitleEvent.class, name = "UpdateGroupTitleEvent"),
-                      @JsonSubTypes.Type(value = UpdateRoleEvent.class, name = "UpdateRoleEvent"),
-                      @JsonSubTypes.Type(value = DeleteGroupEvent.class, name = "DeleteGroupEvent"),
-                      @JsonSubTypes.Type(value = UpdateUserLimitEvent.class, name = "UpdateUserLimitEvent")
-              })
+@JsonTypeInfo(use = JsonTypeInfo.Id.NAME, property = "type")
+@JsonSubTypes({@JsonSubTypes.Type(value = AddUserEvent.class, name = "AddUserEvent"),
+               @JsonSubTypes.Type(value = CreateGroupEvent.class, name = "CreateGroupEvent"),
+               @JsonSubTypes.Type(value = DeleteUserEvent.class, name = "DeleteUserEvent"),
+               @JsonSubTypes.Type(value = UpdateGroupDescriptionEvent.class, name = "UpdateGroupDescriptionEvent"),
+               @JsonSubTypes.Type(value = UpdateGroupTitleEvent.class, name = "UpdateGroupTitleEvent"),
+               @JsonSubTypes.Type(value = UpdateRoleEvent.class, name = "UpdateRoleEvent"),
+               @JsonSubTypes.Type(value = DeleteGroupEvent.class, name = "DeleteGroupEvent"),
+               @JsonSubTypes.Type(value = UpdateUserLimitEvent.class, name = "UpdateUserLimitEvent")})
 @Getter
-@NoArgsConstructor
 @AllArgsConstructor
+@NoArgsConstructor // Lombok needs a default constructor in the base class
 public abstract class Event {
 
-    protected UUID groupId;
-    protected String userId;
+    @JsonProperty("groupid")
+    protected UUID groupid;
+
+    @JsonProperty("userid")
+    protected String userid;
 
     public Group apply(Group group) throws EventException {
-        checkGroupIdMatch(group.getId());
+        checkGroupIdMatch(group.getGroupid());
 
         log.trace("Event angewendet:\t{}", this);
 
@@ -52,7 +50,7 @@ public abstract class Event {
             return;
         }
 
-        if (!this.groupId.equals(groupId)) {
+        if (!groupid.equals(groupId)) {
             throw new GroupIdMismatchException(getClass().toString());
         }
     }
diff --git a/src/main/java/mops/gruppen2/domain/event/UpdateGroupDescriptionEvent.java b/src/main/java/mops/gruppen2/domain/event/UpdateGroupDescriptionEvent.java
index a3fc8ad..b5d5dc4 100644
--- a/src/main/java/mops/gruppen2/domain/event/UpdateGroupDescriptionEvent.java
+++ b/src/main/java/mops/gruppen2/domain/event/UpdateGroupDescriptionEvent.java
@@ -1,5 +1,7 @@
 package mops.gruppen2.domain.event;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
+import lombok.AllArgsConstructor;
 import lombok.Value;
 import lombok.extern.log4j.Log4j2;
 import mops.gruppen2.domain.model.Description;
@@ -11,18 +13,20 @@ import mops.gruppen2.domain.model.User;
  */
 @Log4j2
 @Value
+@AllArgsConstructor
 public class UpdateGroupDescriptionEvent extends Event {
 
-    Description groupDescription;
+    @JsonProperty("desc")
+    Description description;
 
-    public UpdateGroupDescriptionEvent(Group group, User user, Description groupDescription) {
-        super(group.getId(), user.getId());
-        this.groupDescription = groupDescription;
+    public UpdateGroupDescriptionEvent(Group group, User user, Description description) {
+        super(group.getGroupid(), user.getUserid());
+        this.description = description;
     }
 
     @Override
     protected void applyEvent(Group group) {
-        group.setDescription(groupDescription);
+        group.setDescription(description);
 
         log.trace("\t\t\t\t\tNeue Beschreibung: {}", group.getDescription());
     }
diff --git a/src/main/java/mops/gruppen2/domain/event/UpdateGroupTitleEvent.java b/src/main/java/mops/gruppen2/domain/event/UpdateGroupTitleEvent.java
index f698879..96e469f 100644
--- a/src/main/java/mops/gruppen2/domain/event/UpdateGroupTitleEvent.java
+++ b/src/main/java/mops/gruppen2/domain/event/UpdateGroupTitleEvent.java
@@ -1,5 +1,7 @@
 package mops.gruppen2.domain.event;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
+import lombok.AllArgsConstructor;
 import lombok.Value;
 import lombok.extern.log4j.Log4j2;
 import mops.gruppen2.domain.model.Group;
@@ -11,18 +13,20 @@ import mops.gruppen2.domain.model.User;
  */
 @Log4j2
 @Value
+@AllArgsConstructor
 public class UpdateGroupTitleEvent extends Event {
 
-    Title newGroupTitle;
+    @JsonProperty("title")
+    Title title;
 
-    public UpdateGroupTitleEvent(Group group, User user, Title newGroupTitle) {
-        super(group.getId(), user.getId());
-        this.newGroupTitle = newGroupTitle;
+    public UpdateGroupTitleEvent(Group group, User user, Title title) {
+        super(group.getGroupid(), user.getUserid());
+        this.title = title;
     }
 
     @Override
     protected void applyEvent(Group group) {
-        group.setTitle(newGroupTitle);
+        group.setTitle(title);
 
         log.trace("\t\t\t\t\tNeuer Titel: {}", group.getTitle());
     }
diff --git a/src/main/java/mops/gruppen2/domain/event/UpdateRoleEvent.java b/src/main/java/mops/gruppen2/domain/event/UpdateRoleEvent.java
index 2fc57dd..48d0b3c 100644
--- a/src/main/java/mops/gruppen2/domain/event/UpdateRoleEvent.java
+++ b/src/main/java/mops/gruppen2/domain/event/UpdateRoleEvent.java
@@ -1,5 +1,7 @@
 package mops.gruppen2.domain.event;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
+import lombok.AllArgsConstructor;
 import lombok.Value;
 import lombok.extern.log4j.Log4j2;
 import mops.gruppen2.domain.exception.UserNotFoundException;
@@ -8,32 +10,27 @@ import mops.gruppen2.domain.model.Group;
 import mops.gruppen2.domain.model.Role;
 import mops.gruppen2.domain.model.User;
 
-import java.util.UUID;
-
 /**
  * Aktualisiert die Gruppenrolle eines Teilnehmers.
  */
 @Log4j2
 @Value
+@AllArgsConstructor
 public class UpdateRoleEvent extends Event {
 
-    Role newRole;
+    @JsonProperty("role")
+    Role role;
 
-    public UpdateRoleEvent(UUID groupId, String userId, Role newRole) {
-        super(groupId, userId);
-        this.newRole = newRole;
-    }
-
-    public UpdateRoleEvent(Group group, User user, Role newRole) {
-        super(group.getId(), user.getId());
-        this.newRole = newRole;
+    public UpdateRoleEvent(Group group, User user, Role tole) {
+        super(group.getGroupid(), user.getUserid());
+        role = tole;
     }
 
     @Override
     protected void applyEvent(Group group) throws UserNotFoundException {
-        ValidationHelper.throwIfNoMember(group, new User(userId));
+        ValidationHelper.throwIfNoMember(group, new User(userid));
 
-        group.getRoles().put(userId, newRole);
+        group.getRoles().put(userid, role);
 
         log.trace("\t\t\t\t\tNeue Rollen: {}", group.getRoles());
     }
diff --git a/src/main/java/mops/gruppen2/domain/event/UpdateUserLimitEvent.java b/src/main/java/mops/gruppen2/domain/event/UpdateUserLimitEvent.java
index 030f48a..f3fdd56 100644
--- a/src/main/java/mops/gruppen2/domain/event/UpdateUserLimitEvent.java
+++ b/src/main/java/mops/gruppen2/domain/event/UpdateUserLimitEvent.java
@@ -1,5 +1,7 @@
 package mops.gruppen2.domain.event;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
+import lombok.AllArgsConstructor;
 import lombok.Value;
 import lombok.extern.log4j.Log4j2;
 import mops.gruppen2.domain.exception.BadParameterException;
@@ -10,23 +12,25 @@ import mops.gruppen2.domain.model.User;
 
 @Log4j2
 @Value
+@AllArgsConstructor
 public class UpdateUserLimitEvent extends Event {
 
-    Limit userLimit;
+    @JsonProperty("limit")
+    Limit limit;
 
-    public UpdateUserLimitEvent(Group group, User user, Limit userLimit) {
-        super(group.getId(), user.getId());
-        this.userLimit = userLimit;
+    public UpdateUserLimitEvent(Group group, User user, Limit limit) {
+        super(group.getGroupid(), user.getUserid());
+        this.limit = limit;
     }
 
     @Override
     protected void applyEvent(Group group) throws EventException {
-        if (userLimit.getUserLimit() < group.getMembers().size()) {
+        if (limit.getUserLimit() < group.getMembers().size()) {
             throw new BadParameterException("Teilnehmerlimit zu klein.");
         }
 
-        group.setUserLimit(userLimit);
+        group.setLimit(limit);
 
-        log.trace("\t\t\t\t\tNeues UserLimit: {}", group.getUserLimit());
+        log.trace("\t\t\t\t\tNeues UserLimit: {}", group.getLimit());
     }
 }
diff --git a/src/main/java/mops/gruppen2/domain/helper/JsonHelper.java b/src/main/java/mops/gruppen2/domain/helper/JsonHelper.java
index d4a5fa9..93ea49b 100644
--- a/src/main/java/mops/gruppen2/domain/helper/JsonHelper.java
+++ b/src/main/java/mops/gruppen2/domain/helper/JsonHelper.java
@@ -25,7 +25,9 @@ public final class JsonHelper {
 
     public static String serializeEvent(Event event) throws JsonProcessingException {
         ObjectMapper mapper = new ObjectMapper();
-        return mapper.writeValueAsString(event);
+        String payload = mapper.writeValueAsString(event);
+        log.trace(payload);
+        return payload;
     }
 
     /**
diff --git a/src/main/java/mops/gruppen2/domain/helper/ValidationHelper.java b/src/main/java/mops/gruppen2/domain/helper/ValidationHelper.java
index aa05b40..98e17ee 100644
--- a/src/main/java/mops/gruppen2/domain/helper/ValidationHelper.java
+++ b/src/main/java/mops/gruppen2/domain/helper/ValidationHelper.java
@@ -28,7 +28,7 @@ public final class ValidationHelper {
      * Überprüft, ob ein User in einer Gruppe teilnimmt.
      */
     public static boolean checkIfMember(Group group, User user) {
-        return group.getMembers().containsKey(user.getId());
+        return group.getMembers().containsKey(user.getUserid());
     }
 
     public static boolean checkIfLastMember(User user, Group group) {
@@ -39,7 +39,7 @@ public final class ValidationHelper {
      * Überprüft, ob eine Gruppe voll ist.
      */
     public static boolean checkIfGroupFull(Group group) {
-        return group.getMembers().size() >= group.getUserLimit().getUserLimit();
+        return group.getMembers().size() >= group.getLimit().getUserLimit();
     }
 
     /**
@@ -54,7 +54,7 @@ public final class ValidationHelper {
      */
     public static boolean checkIfAdmin(Group group, User user) {
         if (checkIfMember(group, user)) {
-            return group.getRoles().get(user.getId()) == ADMIN;
+            return group.getRoles().get(user.getUserid()) == ADMIN;
         }
         return false;
     }
diff --git a/src/main/java/mops/gruppen2/domain/model/Description.java b/src/main/java/mops/gruppen2/domain/model/Description.java
index 218c094..7db3a30 100644
--- a/src/main/java/mops/gruppen2/domain/model/Description.java
+++ b/src/main/java/mops/gruppen2/domain/model/Description.java
@@ -1,20 +1,21 @@
 package mops.gruppen2.domain.model;
 
-import lombok.Getter;
+import com.fasterxml.jackson.annotation.JsonProperty;
 import lombok.Value;
 
 import javax.validation.constraints.NotBlank;
 import javax.validation.constraints.Size;
 
 @Value
-@Getter
-//@AllArgsConstructor
-//@NoArgsConstructor
 public class Description {
 
-    //private Description() {}
-
     @NotBlank
     @Size(min = 4, max = 512)
+    @JsonProperty("desc")
     String groupDescription;
+
+    @Override
+    public String toString() {
+        return groupDescription;
+    }
 }
diff --git a/src/main/java/mops/gruppen2/domain/model/Group.java b/src/main/java/mops/gruppen2/domain/model/Group.java
index c026219..bd84a2d 100644
--- a/src/main/java/mops/gruppen2/domain/model/Group.java
+++ b/src/main/java/mops/gruppen2/domain/model/Group.java
@@ -19,7 +19,7 @@ import java.util.UUID;
 public class Group {
 
     @EqualsAndHashCode.Include
-    private UUID id;
+    private UUID groupid;
 
     @ToString.Exclude
     private UUID parent;
@@ -30,7 +30,7 @@ public class Group {
     private Description description;
 
     @ToString.Exclude
-    private Limit userLimit = new Limit(1); // Add initial user
+    private Limit limit = new Limit(1); // Add initial user
 
     @ToString.Exclude
     private final Map<String, User> members = new HashMap<>();
diff --git a/src/main/java/mops/gruppen2/domain/model/Limit.java b/src/main/java/mops/gruppen2/domain/model/Limit.java
index d909288..60c0e08 100644
--- a/src/main/java/mops/gruppen2/domain/model/Limit.java
+++ b/src/main/java/mops/gruppen2/domain/model/Limit.java
@@ -1,19 +1,21 @@
 package mops.gruppen2.domain.model;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
 import lombok.Value;
 
 import javax.validation.constraints.Max;
 import javax.validation.constraints.Min;
 
 @Value
-//@Getter
-//@AllArgsConstructor
-//@NoArgsConstructor
 public class Limit {
 
-    //private Limit() {}
-
     @Min(1)
     @Max(999_999)
+    @JsonProperty("limit")
     long userLimit;
+
+    @Override
+    public String toString() {
+        return String.valueOf(userLimit);
+    }
 }
diff --git a/src/main/java/mops/gruppen2/domain/model/Title.java b/src/main/java/mops/gruppen2/domain/model/Title.java
index 2c48778..6c410df 100644
--- a/src/main/java/mops/gruppen2/domain/model/Title.java
+++ b/src/main/java/mops/gruppen2/domain/model/Title.java
@@ -1,19 +1,21 @@
 package mops.gruppen2.domain.model;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
 import lombok.Value;
 
 import javax.validation.constraints.NotBlank;
 import javax.validation.constraints.Size;
 
 @Value
-//@Getter
-//@AllArgsConstructor
-//@NoArgsConstructor
 public class Title {
 
-    //private Title() {}
-
     @NotBlank
     @Size(min = 4, max = 128)
+    @JsonProperty("title")
     String groupTitle;
+
+    @Override
+    public String toString() {
+        return groupTitle;
+    }
 }
diff --git a/src/main/java/mops/gruppen2/domain/model/User.java b/src/main/java/mops/gruppen2/domain/model/User.java
index bb4b0ec..98f60d1 100644
--- a/src/main/java/mops/gruppen2/domain/model/User.java
+++ b/src/main/java/mops/gruppen2/domain/model/User.java
@@ -2,31 +2,30 @@ package mops.gruppen2.domain.model;
 
 import lombok.AllArgsConstructor;
 import lombok.EqualsAndHashCode;
-import lombok.Getter;
-import lombok.NoArgsConstructor;
 import lombok.ToString;
+import lombok.Value;
 import org.keycloak.KeycloakPrincipal;
 import org.keycloak.adapters.springsecurity.token.KeycloakAuthenticationToken;
 
-@Getter
+@Value
 @AllArgsConstructor
-@NoArgsConstructor // Für Jackson: CSV-Import
-@EqualsAndHashCode(onlyExplicitlyIncluded = true)
 @ToString
 public class User {
 
     @EqualsAndHashCode.Include
-    private String id;
+    String userid;
+
+    String givenname;
 
-    private String givenname;
     @ToString.Exclude
-    private String familyname;
+    String familyname;
+
     @ToString.Exclude
-    private String email;
+    String email;
 
     public User(KeycloakAuthenticationToken token) {
         KeycloakPrincipal principal = (KeycloakPrincipal) token.getPrincipal();
-        id = principal.getName();
+        userid = principal.getName();
         givenname = principal.getKeycloakSecurityContext().getIdToken().getGivenName();
         familyname = principal.getKeycloakSecurityContext().getIdToken().getFamilyName();
         email = principal.getKeycloakSecurityContext().getIdToken().getEmail();
@@ -35,10 +34,10 @@ public class User {
     /**
      * User identifizieren sich über die Id, mehr wird also manchmal nicht benötigt.
      *
-     * @param userId Die User Id
+     * @param userid Die User Id
      */
-    public User(String userId) {
-        id = userId;
+    public User(String userid) {
+        this.userid = userid;
         givenname = "";
         familyname = "";
         email = "";
diff --git a/src/main/java/mops/gruppen2/domain/service/EventStoreService.java b/src/main/java/mops/gruppen2/domain/service/EventStoreService.java
index 463ce8b..a2b8eaa 100644
--- a/src/main/java/mops/gruppen2/domain/service/EventStoreService.java
+++ b/src/main/java/mops/gruppen2/domain/service/EventStoreService.java
@@ -84,8 +84,8 @@ public class EventStoreService {
         try {
             String payload = JsonHelper.serializeEvent(event);
             return new EventDTO(null,
-                                event.getGroupId().toString(),
-                                event.getUserId(),
+                                event.getGroupid().toString(),
+                                event.getUserid(),
                                 getEventType(event),
                                 payload);
         } catch (JsonProcessingException e) {
@@ -181,7 +181,7 @@ public class EventStoreService {
 
         return createEvents.stream()
                            .filter(event -> event instanceof CreateGroupEvent)
-                           .map(Event::getGroupId)
+                           .map(Event::getGroupid)
                            .collect(Collectors.toList());
     }
 
@@ -194,14 +194,14 @@ public class EventStoreService {
         List<Event> userEvents = findLatestEventsFromGroupsByUser(user);
         List<UUID> deletedIds = findLatestEventsFromGroupsByType("DeleteGroupEvent")
                 .stream()
-                .map(Event::getGroupId)
+                .map(Event::getGroupid)
                 .collect(Collectors.toList());
 
-        userEvents.removeIf(event -> deletedIds.contains(event.getGroupId()));
+        userEvents.removeIf(event -> deletedIds.contains(event.getGroupid()));
 
         return userEvents.stream()
                          .filter(event -> event instanceof AddUserEvent)
-                         .map(Event::getGroupId)
+                         .map(Event::getGroupid)
                          .collect(Collectors.toList());
     }
 
@@ -244,7 +244,7 @@ public class EventStoreService {
      * @return Eine Liste von einem Add- oder DeleteUserEvent pro Gruppe
      */
     private List<Event> findLatestEventsFromGroupsByUser(User user) {
-        return getEventsFromDTOs(eventStore.findLatestEventDTOsPartitionedByGroupByUser(user.getId()));
+        return getEventsFromDTOs(eventStore.findLatestEventDTOsPartitionedByGroupByUser(user.getUserid()));
     }
 
 
diff --git a/src/main/java/mops/gruppen2/domain/service/GroupService.java b/src/main/java/mops/gruppen2/domain/service/GroupService.java
index 22c4368..4fd0494 100644
--- a/src/main/java/mops/gruppen2/domain/service/GroupService.java
+++ b/src/main/java/mops/gruppen2/domain/service/GroupService.java
@@ -106,7 +106,7 @@ public class GroupService {
      * @return Das neue Teilnehmermaximum
      */
     private static Limit getAdjustedUserLimit(List<User> newUsers, Group group) {
-        return new Limit(Math.max((long) group.getMembers().size() + newUsers.size(), group.getUserLimit().getUserLimit()));
+        return new Limit(Math.max((long) group.getMembers().size() + newUsers.size(), group.getLimit().getUserLimit()));
     }
 
     /**
@@ -122,7 +122,7 @@ public class GroupService {
         ValidationHelper.throwIfNoMember(group, user);
         ValidationHelper.throwIfLastAdmin(user, group);
 
-        Role role = group.getRoles().get(user.getId());
+        Role role = group.getRoles().get(user.getUserid());
         updateRole(user, group, role.toggle());
     }
 
@@ -136,7 +136,7 @@ public class GroupService {
      */
     private Group createGroup(User user, UUID parent, Type type) {
         Event event = new CreateGroupEvent(UUID.randomUUID(),
-                                           user.getId(),
+                                           user,
                                            parent,
                                            type);
         Group group = new Group();
@@ -248,7 +248,7 @@ public class GroupService {
     private void updateRole(User user, Group group, Role role) {
         ValidationHelper.throwIfNoMember(group, user);
 
-        if (role == group.getRoles().get(user.getId())) {
+        if (role == group.getRoles().get(user.getUserid())) {
             return;
         }
 
@@ -266,7 +266,7 @@ public class GroupService {
     public void updateUserLimit(User user, Group group, Limit userLimit) {
         ValidationHelper.throwIfNoAdmin(group, user);
 
-        if (userLimit == group.getUserLimit()) {
+        if (userLimit == group.getLimit()) {
             return;
         }
 
diff --git a/src/main/java/mops/gruppen2/domain/service/InviteService.java b/src/main/java/mops/gruppen2/domain/service/InviteService.java
index 64ba53e..669b3dd 100644
--- a/src/main/java/mops/gruppen2/domain/service/InviteService.java
+++ b/src/main/java/mops/gruppen2/domain/service/InviteService.java
@@ -22,16 +22,16 @@ public class InviteService {
 
     void createLink(Group group) {
         inviteRepository.save(new InviteLinkDTO(null,
-                                                group.getId().toString(),
+                                                group.getGroupid().toString(),
                                                 UUID.randomUUID().toString()));
 
-        log.debug("Link wurde erzeugt! (Gruppe: {})", group.getId());
+        log.debug("Link wurde erzeugt! (Gruppe: {})", group.getGroupid());
     }
 
     void destroyLink(Group group) {
-        inviteRepository.deleteLinkOfGroup(group.getId().toString());
+        inviteRepository.deleteLinkOfGroup(group.getGroupid().toString());
 
-        log.debug("Link wurde zerstört! (Gruppe: {})", group.getId());
+        log.debug("Link wurde zerstört! (Gruppe: {})", group.getGroupid());
     }
 
     public UUID getGroupIdFromLink(String link) {
@@ -45,10 +45,10 @@ public class InviteService {
 
     public String getLinkByGroup(Group group) {
         try {
-            return inviteRepository.findLinkByGroupId(group.getId().toString());
+            return inviteRepository.findLinkByGroupId(group.getGroupid().toString());
         } catch (Exception e) {
-            log.error("Link zu Gruppe ({}) konnte nicht gefunden werden!", group.getId(), e);
-            throw new NoInviteExistException(group.getId().toString());
+            log.error("Link zu Gruppe ({}) konnte nicht gefunden werden!", group.getGroupid(), e);
+            throw new NoInviteExistException(group.getGroupid().toString());
         }
     }
 }
diff --git a/src/main/java/mops/gruppen2/domain/service/ProjectionService.java b/src/main/java/mops/gruppen2/domain/service/ProjectionService.java
index e7355b6..b241872 100644
--- a/src/main/java/mops/gruppen2/domain/service/ProjectionService.java
+++ b/src/main/java/mops/gruppen2/domain/service/ProjectionService.java
@@ -48,7 +48,7 @@ public class ProjectionService {
     static List<Group> projectGroups(List<Event> events) throws EventException {
         Map<UUID, Group> groupMap = new HashMap<>();
 
-        events.forEach(event -> event.apply(getOrCreateGroup(groupMap, event.getGroupId())));
+        events.forEach(event -> event.apply(getOrCreateGroup(groupMap, event.getGroupid())));
 
         return new ArrayList<>(groupMap.values());
     }
@@ -119,7 +119,6 @@ public class ProjectionService {
      * @throws EventException Projektionsfehler
      */
     @Cacheable("groups")
-    //TODO: remove userID param
     public List<Group> projectPublicGroups() throws EventException {
         List<UUID> groupIds = eventStoreService.findExistingGroupIds();
         List<Event> events = eventStoreService.findEventsByGroupAndType(groupIds,
@@ -219,7 +218,7 @@ public class ProjectionService {
     void removeUserGroups(List<Group> groups, User user) {
         List<UUID> userGroups = eventStoreService.findExistingUserGroups(user);
 
-        groups.removeIf(group -> userGroups.contains(group.getId()));
+        groups.removeIf(group -> userGroups.contains(group.getGroupid()));
     }
 }
 
diff --git a/src/main/java/mops/gruppen2/web/GroupCreationController.java b/src/main/java/mops/gruppen2/web/GroupCreationController.java
index 60fb386..9cc435c 100644
--- a/src/main/java/mops/gruppen2/web/GroupCreationController.java
+++ b/src/main/java/mops/gruppen2/web/GroupCreationController.java
@@ -70,6 +70,6 @@ public class GroupCreationController {
             groupService.addUsersToGroup(CsvHelper.readCsvFile(create.getFile()), group, user);
         }
 
-        return "redirect:/gruppen2/details/" + IdHelper.uuidToString(group.getId());
+        return "redirect:/gruppen2/details/" + IdHelper.uuidToString(group.getGroupid());
     }
 }
diff --git a/src/main/java/mops/gruppen2/web/GroupDetailsController.java b/src/main/java/mops/gruppen2/web/GroupDetailsController.java
index 577887e..843cba1 100644
--- a/src/main/java/mops/gruppen2/web/GroupDetailsController.java
+++ b/src/main/java/mops/gruppen2/web/GroupDetailsController.java
@@ -204,7 +204,7 @@ public class GroupDetailsController {
         ValidationHelper.throwIfNoAdmin(group, user);
 
         // Der eingeloggte User kann sich nicht selbst entfernen (er kann aber verlassen)
-        if (!userId.equals(user.getId())) {
+        if (!userId.equals(user.getUserid())) {
             groupService.deleteUser(new User(userId), group);
         }
 
diff --git a/src/main/java/mops/gruppen2/web/SearchAndInviteController.java b/src/main/java/mops/gruppen2/web/SearchAndInviteController.java
index 34858ab..db51f2c 100644
--- a/src/main/java/mops/gruppen2/web/SearchAndInviteController.java
+++ b/src/main/java/mops/gruppen2/web/SearchAndInviteController.java
@@ -71,12 +71,12 @@ public class SearchAndInviteController {
 
         // Gruppe öffentlich
         if (group.getType() == Type.PUBLIC) {
-            return "redirect:/gruppen2/details/" + group.getId();
+            return "redirect:/gruppen2/details/" + group.getGroupid();
         }
 
         // Bereits Mitglied
         if (ValidationHelper.checkIfMember(group, user)) {
-            return "redirect:/gruppen2/details/" + group.getId();
+            return "redirect:/gruppen2/details/" + group.getGroupid();
         }
 
         return "link";
diff --git a/src/main/resources/templates/details.html b/src/main/resources/templates/details.html
index 907081a..5bf76fc 100644
--- a/src/main/resources/templates/details.html
+++ b/src/main/resources/templates/details.html
@@ -11,7 +11,7 @@
 <main th:fragment="bodycontent">
     <div class="container-fluid">
 
-        <h1 class="def-cursor" th:text="${group.getTitle().getGroupTitle()}"></h1>
+        <h1 class="def-cursor" th:text="${group.getTitle()}"></h1>
 
         <div class="row">
             <!--Gruppendetails-->
@@ -27,7 +27,7 @@
                         <!--Spacer-->
                         <span class="col"></span>
 
-                        <form method="post" th:action="@{/gruppen2/details/{id}/leave(id=${group.getId()})}">
+                        <form method="post" th:action="@{/gruppen2/details/{id}/leave(id=${group.getGroupid()})}">
                             <button class="btn btn-danger btn-bar" type="submit">Gruppe verlassen
                             </button>
                         </form>
@@ -40,13 +40,13 @@
                 <!--Anzahl Text-->
                 <div class="mb-2">
                     <span>Teilnehmer: </span>
-                    <span th:text="${group.getMembers().size() + ' von ' + group.getUserLimit().getUserLimit()}"></span>
+                    <span th:text="${group.getMembers().size() + ' von ' + group.getLimit().getUserLimit()}"></span>
                 </div>
 
                 <!--Bearbeiten-Button-->
-                <div class="mb-2" th:if="${group.getRoles().get(user.getId()) == admin}">
+                <div class="mb-2" th:if="${group.getRoles().get(user.getUserid()) == admin}">
                     <form method="get"
-                          th:action="@{/gruppen2/details/{id}/edit(id=${group.getId()})}">
+                          th:action="@{/gruppen2/details/{id}/edit(id=${group.getGroupid()})}">
                         <button class="btn btn-secondary btn-block">Gruppe verwalten</button>
                     </form>
                 </div>
diff --git a/src/main/resources/templates/edit.html b/src/main/resources/templates/edit.html
index 103a702..fa04b00 100644
--- a/src/main/resources/templates/edit.html
+++ b/src/main/resources/templates/edit.html
@@ -10,19 +10,19 @@
 
 <main th:fragment="bodycontent">
     <div class="container-fluid">
-        <h1 class="def-cursor" th:text="${group.getTitle().getGroupTitle()}"></h1>
+        <h1 class="def-cursor" th:text="${group.getTitle()}"></h1>
 
         <!--Fertig oder löschen-->
         <div class="content">
             <div class="row">
-                <form method="get" th:action="@{/gruppen2/details/{id}(id=${group.getId()})}">
+                <form method="get" th:action="@{/gruppen2/details/{id}(id=${group.getGroupid()})}">
                     <button class="btn btn-primary">Fertig</button>
                 </form>
 
                 <!--Spacer-->
                 <span class="col"></span>
 
-                <form method="post" th:action="@{/gruppen2/details/{id}/edit/destroy(id=${group.getId()})}">
+                <form method="post" th:action="@{/gruppen2/details/{id}/edit/destroy(id=${group.getGroupid()})}">
                     <button class="btn btn-danger btn-bar" type="submit">Gruppe löschen
                     </button>
                 </form>
@@ -50,7 +50,7 @@
 
             <!--Beschreibung + Titel-->
             <div class="content-text">
-                <form th:action="@{/gruppen2/details/{id}/edit/meta(id=${group.getId()})}"
+                <form th:action="@{/gruppen2/details/{id}/edit/meta(id=${group.getGroupid()})}"
                       method="post">
 
                     <div th:replace="~{fragments/forms :: meta}"></div>
@@ -63,7 +63,7 @@
 
             <!--Userlimit-->
             <div class="content-text-in">
-                <form th:action="@{/gruppen2/details/{id}/edit/userlimit(id=${group.getId()})}"
+                <form th:action="@{/gruppen2/details/{id}/edit/userlimit(id=${group.getGroupid()})}"
                       method="post">
 
                     <div th:replace="~{fragments/forms :: userlimit}"></div>
@@ -76,7 +76,7 @@
 
             <!--CSV Import-->
             <div class="content-text mb-0">
-                <form th:action="@{/gruppen2/details/{id}/edit/csv(id=${group.getId()})}"
+                <form th:action="@{/gruppen2/details/{id}/edit/csv(id=${group.getGroupid()})}"
                       th:if="${account.getRoles().contains('orga')}"
                       enctype="multipart/form-data" method="post">
 
@@ -103,13 +103,13 @@
                     </div>
 
                     <div class="d-flex">
-                        <form th:action="@{/gruppen2/details/{id}/edit/delete/{userid}(id=${group.getId()}, userid=${member.getId()})}"
-                              th:unless="${member.getId() == account.getName()}"
+                        <form th:action="@{/gruppen2/details/{id}/edit/delete/{userid}(id=${group.getGroupid()}, userid=${member.getUserid()})}"
+                              th:unless="${member.getUserid() == account.getName()}"
                               method="post">
                             <button type="submit" class="btn btn-danger mr-2">Entfernen</button>
                         </form>
 
-                        <form th:action="@{/gruppen2/details/{id}/edit/role/{userid}(id=${group.getId()}, userid=${member.getId()})}"
+                        <form th:action="@{/gruppen2/details/{id}/edit/role/{userid}(id=${group.getGroupid()}, userid=${member.getUserid()})}"
                               method="post">
                             <button type="submit" class="btn btn-warning">Rolle ändern</button>
                         </form>
diff --git a/src/main/resources/templates/fragments/forms.html b/src/main/resources/templates/fragments/forms.html
index 990f58e..ba4a19a 100644
--- a/src/main/resources/templates/fragments/forms.html
+++ b/src/main/resources/templates/fragments/forms.html
@@ -11,7 +11,7 @@
             <span class="input-group-text text-monospace">Gruppentitel:</span>
         </div>
         <input type="text" class="form-control" name="groupTitle" minlength="4" maxlength="128"
-               th:value="${group?.getTitle()?.getGroupTitle()}" required>
+               th:value="${group?.getTitle()}" required>
     </div>
 
     <!--Gruppenbeschreibung-->
@@ -50,8 +50,8 @@
             <input type="hidden" id="parentdummy" name="parent" value="00000000-0000-0000-0000-000000000000" disabled>
             <select class="custom-select" id="parentselect" name="parent">
                 <option value="00000000-0000-0000-0000-000000000000" selected>Keiner</option>
-                <option th:each="lecture : ${lectures}" th:value="${lecture.getId()}"
-                        th:text="${lecture.getTitle().getGroupTitle()}"></option>
+                <option th:each="lecture : ${lectures}" th:value="${lecture.getGroupid()}"
+                        th:text="${lecture.getTitle()}"></option>
             </select>
         </div>
     </div>
@@ -62,16 +62,16 @@
     <label for="userlimit">Teilnehmeranzahl:</label>
     <div class="btn-toolbar row mx-0" id="userlimit">
         <input type="hidden" name="userLimit" id="limit" value="999999"
-               th:disabled="${group != null && group.getUserLimit().getUserLimit() < 999999} ? 'disabled' : 'false'">
+               th:disabled="${group != null && group.getLimit().getUserLimit() < 999999} ? 'disabled' : 'false'">
         <div class="btn-group btn-group-toggle col-sm-4 px-0" data-toggle="buttons">
             <label class="btn btn-secondary active" onclick="disable('#limitselect'); enable('#limit')">
                 <input type="radio"
-                       th:checked="${group != null && group.getUserLimit().getUserLimit() < 999999} ? 'false' : 'checked'">
+                       th:checked="${group != null && group.getLimit().getUserLimit() < 999999} ? 'false' : 'checked'">
                 Unbegrenzt
             </label>
             <label class="btn btn-secondary" onclick="enable('#limitselect'); disable('#limit')">
                 <input type="radio"
-                       th:checked="${group != null && group.getUserLimit().getUserLimit() < 999999} ? 'checked' : 'false'">
+                       th:checked="${group != null && group.getLimit().getUserLimit() < 999999} ? 'checked' : 'false'">
                 Begrenzt
             </label>
         </div>
@@ -82,9 +82,9 @@
                 <span class="input-group-text text-monospace">Limit:</span>
             </div>
             <input type="number" class="form-control" name="userLimit"
-                   th:value="${group != null} ? ${group.getUserLimit().getUserLimit()} : '999999'"
+                   th:value="${group != null} ? ${group.getLimit().getUserLimit()} : '999999'"
                    min="1" max="999999" id="limitselect" required
-                   th:disabled="${group != null && group.getUserLimit().getUserLimit() < 999999} ? 'false' : 'disabled'">
+                   th:disabled="${group != null && group.getLimit().getUserLimit() < 999999} ? 'false' : 'disabled'">
             <div class="input-group-append">
                 <span class="input-group-text text-monospace">Teilnehmer</span>
             </div>
diff --git a/src/main/resources/templates/fragments/groups.html b/src/main/resources/templates/fragments/groups.html
index 4d31d46..adcd03d 100644
--- a/src/main/resources/templates/fragments/groups.html
+++ b/src/main/resources/templates/fragments/groups.html
@@ -15,9 +15,9 @@
           th:if='${group.getType() == lecture}'>Veranstaltung</span>
 
     <span class="badge badge-pill parent"
-          th:unless="${parent == null || parent?.getTitle()?.getGroupTitle() == null|| parent?.getTitle()?.getGroupTitle() == ''}"
-          th:title="${'Die Gruppe gehört zur Veranstaltung ' + parent.getTitle().getGroupTitle() + '.'}"
-          th:text="${parent.getTitle().getGroupTitle()}">Parent</span>
+          th:unless="${parent == null || parent?.getTitle() == null|| parent?.getTitle() == ''}"
+          th:title="${'Die Gruppe gehört zur Veranstaltung ' + parent.getTitle() + '.'}"
+          th:text="${parent.getTitle()}">Parent</span>
 
     <!--Needs completly projected (cached) groups-->
     <!--<span class="badge badge-success float-right"
@@ -28,7 +28,7 @@
 <!--User Badges-->
 <th:block th:fragment="userbadges">
     <span class="badge badge-success align-self-start ml-2"
-          th:if="${group.getRoles().get(member.getId()) == admin}">Admin</span>
+          th:if="${group.getRoles().get(member.getUserid()) == admin}">Admin</span>
 </th:block>
 
 <th:block th:fragment="groupcontent">
@@ -48,21 +48,21 @@
 <!--Buttonbar zum Gruppe beitreten-->
 <th:block th:fragment="joingroup">
     <div class="content-heading">
-        <span th:if="${group.getMembers().size() < group.getUserLimit().getUserLimit()}">
+        <span th:if="${group.getMembers().size() < group.getLimit().getUserLimit()}">
             Möchtest du dieser Gruppe beitreten?
         </span>
-        <span th:unless="${group.getMembers().size() < group.getUserLimit().getUserLimit()}">
+        <span th:unless="${group.getMembers().size() < group.getLimit().getUserLimit()}">
             Diese Gruppe hat ihre maximale Teilnehmeranzahl erreicht.
         </span>
     </div>
 
     <div class="row">
-        <form method="post" th:action="@{/gruppen2/details/{id}/join(id = ${group.getId()})}"
-              th:if="${group.getMembers().size() < group.getUserLimit().getUserLimit()}">
+        <form method="post" th:action="@{/gruppen2/details/{id}/join(id = ${group.getGroupId()})}"
+              th:if="${group.getMembers().size() < group.getLimit().getUserLimit()}">
             <button class="btn btn-success" type="submit">Gruppe beitreten.</button>
         </form>
 
-        <div class="col" th:if="${group.getMembers().size() < group.getUserLimit().getUserLimit()}"></div>
+        <div class="col" th:if="${group.getMembers().size() < group.getLimit().getUserLimit()}"></div>
 
         <a class="btn btn-primary" href="/gruppen2"
            type="submit">Startseite.</a>
diff --git a/src/main/resources/templates/index.html b/src/main/resources/templates/index.html
index 9873c76..7fb5c52 100644
--- a/src/main/resources/templates/index.html
+++ b/src/main/resources/templates/index.html
@@ -16,8 +16,8 @@
         <!--Gruppenliste belegte Gruppen-->
         <div class="content" th:each="group: ${groups}">
             <div class="content-heading row">
-                <a class="link col" th:href="@{/gruppen2/details/{id}(id=${group.getId()})}"
-                   th:text="${group.getTitle().getGroupTitle()}"></a>
+                <a class="link col" th:href="@{/gruppen2/details/{id}(id=${group.getGroupid()})}"
+                   th:text="${group.getTitle()}"></a>
 
                 <span th:replace="~{fragments/groups :: badges}"></span>
             </div>
diff --git a/src/main/resources/templates/link.html b/src/main/resources/templates/link.html
index d4ff7b2..5a5741a 100644
--- a/src/main/resources/templates/link.html
+++ b/src/main/resources/templates/link.html
@@ -10,7 +10,7 @@
 
 <main th:fragment="bodycontent">
     <div class="container-fluid">
-        <h1 class="def-cursor" th:text="${group.getTitle().getGroupTitle()}"></h1>
+        <h1 class="def-cursor" th:text="${group.getTitle()}"></h1>
 
         <div class="content" th:insert="~{fragments/groups :: groupcontent}"></div>
 
diff --git a/src/main/resources/templates/preview.html b/src/main/resources/templates/preview.html
index 4393c49..8f8af66 100644
--- a/src/main/resources/templates/preview.html
+++ b/src/main/resources/templates/preview.html
@@ -10,7 +10,7 @@
 
 <main th:fragment="bodycontent">
     <div class="container-fluid">
-        <h1 class="def-cursor" th:text="${group.getTitle().getGroupTitle()}"></h1>
+        <h1 class="def-cursor" th:text="${group.getTitle()}"></h1>
 
         <div class="content" th:insert="~{fragments/groups :: groupcontent}"></div>
 
diff --git a/src/main/resources/templates/search.html b/src/main/resources/templates/search.html
index 0a9c3cd..21dcd4d 100644
--- a/src/main/resources/templates/search.html
+++ b/src/main/resources/templates/search.html
@@ -31,8 +31,8 @@
             <div class="content-heading row">
                 <span th:replace="~{fragments/groups :: badges}"></span>
 
-                <a class="link col" th:href="@{/gruppen2/details/{id}(id=${group.getId()})}"
-                   th:text="${group.getTitle().getGroupTitle()}"></a>
+                <a class="link col" th:href="@{/gruppen2/details/{id}(id=${group.getGroupid()})}"
+                   th:text="${group.getTitle()}"></a>
             </div>
             <div class="content-text-in">
                 <span th:text="${group.getDescription().getGroupDescription()}"></span>
diff --git a/src/test/java/mops/gruppen2/TestBuilder.java b/src/test/java/mops/gruppen2/TestBuilder.java
index 1255fe3..3ac61d7 100644
--- a/src/test/java/mops/gruppen2/TestBuilder.java
+++ b/src/test/java/mops/gruppen2/TestBuilder.java
@@ -230,7 +230,7 @@ public class TestBuilder {
         Collections.shuffle(shuffle);
 
         for (Event event : shuffle) {
-            removeEvents.add(new DeleteUserEvent(event.getGroupId(), event.getUserId()));
+            removeEvents.add(new DeleteUserEvent(event.getGroupid(), event.getUserid()));
 
             if (removeEvents.size() >= count) {
                 break;
@@ -249,7 +249,7 @@ public class TestBuilder {
      */
     public static List<Event> deleteUserEvents(Group group) {
         return group.getMembers().parallelStream()
-                    .map(user -> deleteUserEvent(group.getId(), user.getId()))
+                    .map(user -> deleteUserEvent(group.getGroupid(), user.getUserId()))
                     .collect(Collectors.toList());
     }
 
diff --git a/src/test/java/mops/gruppen2/domain/event/CreateGroupEventTest.java b/src/test/java/mops/gruppen2/domain/event/CreateGroupEventTest.java
index 24f4c5e..93e4fdf 100644
--- a/src/test/java/mops/gruppen2/domain/event/CreateGroupEventTest.java
+++ b/src/test/java/mops/gruppen2/domain/event/CreateGroupEventTest.java
@@ -21,7 +21,7 @@ class CreateGroupEventTest {
 
         assertThat(group.getMembers()).hasSize(0);
         assertThat(group.getType()).isEqualTo(Type.PUBLIC);
-        assertThat(group.getId()).isEqualTo(uuidMock(0));
+        assertThat(group.getGroupid()).isEqualTo(uuidMock(0));
         assertThat(group.getParent()).isEqualTo(uuidMock(1));
     }
 }
diff --git a/src/test/java/mops/gruppen2/domain/event/DeleteGroupEventTest.java b/src/test/java/mops/gruppen2/domain/event/DeleteGroupEventTest.java
index 8af3272..db3d022 100644
--- a/src/test/java/mops/gruppen2/domain/event/DeleteGroupEventTest.java
+++ b/src/test/java/mops/gruppen2/domain/event/DeleteGroupEventTest.java
@@ -22,8 +22,8 @@ class DeleteGroupEventTest {
 
         assertThat(group.getMembers()).isEmpty();
         assertThat(group.getType()).isEqualTo(null);
-        assertThat(group.getUserLimit()).isEqualTo(0);
-        assertThat(group.getId()).isEqualTo(uuidMock(0));
+        assertThat(group.getLimit()).isEqualTo(0);
+        assertThat(group.getGroupid()).isEqualTo(uuidMock(0));
         assertThat(group.getParent()).isEqualTo(null);
     }
 }
diff --git a/src/test/java/mops/gruppen2/domain/event/UpdateUserLimitEventTest.java b/src/test/java/mops/gruppen2/domain/event/UpdateUserLimitEventTest.java
index 64bdced..f28ffa9 100644
--- a/src/test/java/mops/gruppen2/domain/event/UpdateUserLimitEventTest.java
+++ b/src/test/java/mops/gruppen2/domain/event/UpdateUserLimitEventTest.java
@@ -20,7 +20,7 @@ class UpdateUserLimitEventTest {
 
         Group group = apply(createEvent, updateEvent);
 
-        assertThat(group.getUserLimit()).isEqualTo(5);
+        assertThat(group.getLimit()).isEqualTo(5);
     }
 
     @Test
diff --git a/src/test/java/mops/gruppen2/domain/service/EventStoreServiceTest.java b/src/test/java/mops/gruppen2/domain/service/EventStoreServiceTest.java
index b943017..5b00a69 100644
--- a/src/test/java/mops/gruppen2/domain/service/EventStoreServiceTest.java
+++ b/src/test/java/mops/gruppen2/domain/service/EventStoreServiceTest.java
@@ -72,8 +72,8 @@ class EventStoreServiceTest {
 
         EventDTO dto = EventStoreService.getDTOFromEvent(event);
 
-        assertThat(dto.getGroup_id()).isEqualTo(event.getGroupId().toString());
-        assertThat(dto.getUser_id()).isEqualTo(event.getUserId());
+        assertThat(dto.getGroup_id()).isEqualTo(event.getGroupid().toString());
+        assertThat(dto.getUser_id()).isEqualTo(event.getUserid());
         assertThat(dto.getEvent_id()).isEqualTo(null);
         assertThat(dto.getEvent_type()).isEqualTo("CreateGroupEvent");
     }
diff --git a/src/test/java/mops/gruppen2/domain/service/GroupServiceTest.java b/src/test/java/mops/gruppen2/domain/service/GroupServiceTest.java
index abfb15d..ac09bc0 100644
--- a/src/test/java/mops/gruppen2/domain/service/GroupServiceTest.java
+++ b/src/test/java/mops/gruppen2/domain/service/GroupServiceTest.java
@@ -108,8 +108,8 @@ class GroupServiceTest {
         List<UUID> groupIds = Arrays.asList(uuidMock(0), uuidMock(1));
 
         assertThat(eventStoreService.findGroupEvents(groupIds)).hasSize(2);
-        assertThat(eventStoreService.findGroupEvents(groupIds).get(0).getGroupId()).isEqualTo(uuidMock(0));
-        assertThat(eventStoreService.findGroupEvents(groupIds).get(1).getGroupId()).isEqualTo(uuidMock(1));
+        assertThat(eventStoreService.findGroupEvents(groupIds).get(0).getGroupid()).isEqualTo(uuidMock(0));
+        assertThat(eventStoreService.findGroupEvents(groupIds).get(1).getGroupid()).isEqualTo(uuidMock(1));
     }
 
     //TODO: ProjectionServiceTest
diff --git a/src/test/java/mops/gruppen2/web/APIControllerTest.java b/src/test/java/mops/gruppen2/web/APIControllerTest.java
index 0851269..dad8e69 100644
--- a/src/test/java/mops/gruppen2/web/APIControllerTest.java
+++ b/src/test/java/mops/gruppen2/web/APIControllerTest.java
@@ -161,7 +161,7 @@ class APIControllerTest {
     void getGroupFromId_singleGroup() {
         eventStoreService.saveAll(createPrivateGroupEvent(uuidMock(0)));
 
-        assertThat(apiController.getApiGroup(uuidMock(0).toString()).getId()).isEqualTo(uuidMock(0));
+        assertThat(apiController.getApiGroup(uuidMock(0).toString()).getGroupid()).isEqualTo(uuidMock(0));
     }
 
     @Test