diff --git a/app/build.gradle b/app/build.gradle
index 8138321..7bb57bf 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -10,7 +10,7 @@ configurations {
 }
 
 dependencies {
-    implementation project(":api")
+    implementation project(":client-api")
     developmentOnly("org.springframework.boot:spring-boot-devtools")
     implementation 'org.springframework.boot:spring-boot-starter-aop'
     implementation 'org.springframework.boot:spring-boot-starter-security'
diff --git a/api/build.gradle b/client-api/build.gradle
similarity index 100%
rename from api/build.gradle
rename to client-api/build.gradle
diff --git a/api/src/main/java/ru/dragonestia/picker/api/exception/ApiException.java b/client-api/src/main/java/ru/dragonestia/picker/api/exception/ApiException.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/exception/ApiException.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/exception/ApiException.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/exception/ExceptionFactory.java b/client-api/src/main/java/ru/dragonestia/picker/api/exception/ExceptionFactory.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/exception/ExceptionFactory.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/exception/ExceptionFactory.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/exception/InvalidNodeIdentifierException.java b/client-api/src/main/java/ru/dragonestia/picker/api/exception/InvalidNodeIdentifierException.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/exception/InvalidNodeIdentifierException.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/exception/InvalidNodeIdentifierException.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/exception/InvalidRoomIdentifierException.java b/client-api/src/main/java/ru/dragonestia/picker/api/exception/InvalidRoomIdentifierException.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/exception/InvalidRoomIdentifierException.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/exception/InvalidRoomIdentifierException.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/exception/InvalidUsernamesException.java b/client-api/src/main/java/ru/dragonestia/picker/api/exception/InvalidUsernamesException.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/exception/InvalidUsernamesException.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/exception/InvalidUsernamesException.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/exception/NoRoomsAvailableException.java b/client-api/src/main/java/ru/dragonestia/picker/api/exception/NoRoomsAvailableException.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/exception/NoRoomsAvailableException.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/exception/NoRoomsAvailableException.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/exception/NodeAlreadyExistException.java b/client-api/src/main/java/ru/dragonestia/picker/api/exception/NodeAlreadyExistException.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/exception/NodeAlreadyExistException.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/exception/NodeAlreadyExistException.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/exception/NodeNotFoundException.java b/client-api/src/main/java/ru/dragonestia/picker/api/exception/NodeNotFoundException.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/exception/NodeNotFoundException.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/exception/NodeNotFoundException.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/exception/NotPersistedNodeException.java b/client-api/src/main/java/ru/dragonestia/picker/api/exception/NotPersistedNodeException.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/exception/NotPersistedNodeException.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/exception/NotPersistedNodeException.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/exception/RoomAlreadyExistException.java b/client-api/src/main/java/ru/dragonestia/picker/api/exception/RoomAlreadyExistException.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/exception/RoomAlreadyExistException.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/exception/RoomAlreadyExistException.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/exception/RoomAreFullException.java b/client-api/src/main/java/ru/dragonestia/picker/api/exception/RoomAreFullException.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/exception/RoomAreFullException.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/exception/RoomAreFullException.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/exception/RoomNotFoundException.java b/client-api/src/main/java/ru/dragonestia/picker/api/exception/RoomNotFoundException.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/exception/RoomNotFoundException.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/exception/RoomNotFoundException.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/NodeRepository.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/NodeRepository.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/NodeRepository.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/NodeRepository.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/RoomPickerRepository.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/RoomPickerRepository.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/RoomPickerRepository.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/RoomPickerRepository.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/RoomRepository.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/RoomRepository.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/RoomRepository.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/RoomRepository.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/UserRepository.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/UserRepository.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/UserRepository.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/UserRepository.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/details/NodeDetails.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/details/NodeDetails.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/details/NodeDetails.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/details/NodeDetails.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/details/RoomDetails.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/details/RoomDetails.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/details/RoomDetails.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/details/RoomDetails.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/details/UserDetails.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/details/UserDetails.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/details/UserDetails.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/details/UserDetails.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/response/ErrorResponse.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/response/ErrorResponse.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/response/ErrorResponse.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/response/ErrorResponse.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/response/LinkUsersWithRoomResponse.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/response/LinkUsersWithRoomResponse.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/response/LinkUsersWithRoomResponse.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/response/LinkUsersWithRoomResponse.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/response/LinkedRoomsWithUserResponse.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/response/LinkedRoomsWithUserResponse.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/response/LinkedRoomsWithUserResponse.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/response/LinkedRoomsWithUserResponse.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/response/NodeDetailsResponse.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/response/NodeDetailsResponse.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/response/NodeDetailsResponse.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/response/NodeDetailsResponse.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/response/NodeListResponse.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/response/NodeListResponse.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/response/NodeListResponse.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/response/NodeListResponse.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/response/RoomInfoResponse.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/response/RoomInfoResponse.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/response/RoomInfoResponse.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/response/RoomInfoResponse.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/response/RoomListResponse.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/response/RoomListResponse.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/response/RoomListResponse.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/response/RoomListResponse.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/response/RoomPickerInfoResponse.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/response/RoomPickerInfoResponse.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/response/RoomPickerInfoResponse.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/response/RoomPickerInfoResponse.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/response/RoomUserListResponse.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/response/RoomUserListResponse.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/response/RoomUserListResponse.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/response/RoomUserListResponse.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/response/SearchUserResponse.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/response/SearchUserResponse.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/response/SearchUserResponse.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/response/SearchUserResponse.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/response/UserDetailsResponse.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/response/UserDetailsResponse.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/response/UserDetailsResponse.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/response/UserDetailsResponse.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/response/type/RNode.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/response/type/RNode.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/response/type/RNode.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/response/type/RNode.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/response/type/RRoom.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/response/type/RRoom.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/response/type/RRoom.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/response/type/RRoom.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/response/type/RUser.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/response/type/RUser.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/response/type/RUser.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/response/type/RUser.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/repository/response/type/type/PickingMode.java b/client-api/src/main/java/ru/dragonestia/picker/api/repository/response/type/type/PickingMode.java
similarity index 100%
rename from api/src/main/java/ru/dragonestia/picker/api/repository/response/type/type/PickingMode.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/repository/response/type/type/PickingMode.java
diff --git a/api/src/main/java/ru/dragonestia/picker/api/utils/ValidateIdentifier.java b/client-api/src/main/java/ru/dragonestia/picker/api/utils/ValidateIdentifier.java
similarity index 58%
rename from api/src/main/java/ru/dragonestia/picker/api/utils/ValidateIdentifier.java
rename to client-api/src/main/java/ru/dragonestia/picker/api/utils/ValidateIdentifier.java
index 5363618..c88a2d6 100644
--- a/api/src/main/java/ru/dragonestia/picker/api/utils/ValidateIdentifier.java
+++ b/client-api/src/main/java/ru/dragonestia/picker/api/utils/ValidateIdentifier.java
@@ -5,14 +5,14 @@ public class ValidateIdentifier {
     private ValidateIdentifier() {}
 
     public static boolean forNode(String nodeId) {
-        return nodeId.matches("^[a-z\\d-]+$");
+        return nodeId.matches("^(?!-)[a-z\\d-]{0,31}[a-z\\d](?!-)$");
     }
 
     public static boolean forRoom(String roomId) {
-        return roomId.matches("^[a-z\\d-]+$");
+        return roomId.matches("^(?!-)[a-z\\d-]{0,31}[a-z\\d](?!-)$");
     }
 
     public static boolean forUser(String username) {
-        return username.matches("^[aA-zZ\\d-.\\s:@_;]+$");
+        return username.matches("^[aA-zZ\\d-.\\s:@_;]{1,64}$");
     }
 }
diff --git a/control-panel/build.gradle b/control-panel/build.gradle
index d06cadc..677c16e 100644
--- a/control-panel/build.gradle
+++ b/control-panel/build.gradle
@@ -27,7 +27,7 @@ vaadin {
 }
 
 dependencies {
-    implementation project(":api")
+    implementation project(":client-api")
 
     implementation 'com.vaadin:vaadin-spring-boot-starter'
     compileOnly 'org.projectlombok:lombok'
diff --git a/settings.gradle b/settings.gradle
index 4d6c145..a98138d 100644
--- a/settings.gradle
+++ b/settings.gradle
@@ -3,4 +3,5 @@ rootProject.name = 'RoomPicker'
 include 'app'
 include 'control-panel'
 include 'api'
+include 'client-api'