diff --git a/main.go b/main.go
index db193a1..3ccc5eb 100644
--- a/main.go
+++ b/main.go
@@ -69,6 +69,7 @@ func InitialRoutineManager(bot *tgbotapi.BotAPI, commandManager *cli.CommandMana
 
 	rm.RegisterRoutine(routines.NewCommandRoutine(commandManager))
 	rm.RegisterRoutine(routines.NewDatabaseRoutine(service))
+	rm.RegisterRoutine(routines.NewJoinCheckerRoutine())
 
 	return rm
 }
diff --git a/telegram/manager.go b/telegram/manager.go
index b738bfd..b88f57e 100644
--- a/telegram/manager.go
+++ b/telegram/manager.go
@@ -2,6 +2,7 @@ package telegram
 
 import (
 	"git.dragon-labs.de/alphyron/group_helper/logic"
+	"git.dragon-labs.de/alphyron/group_helper/models"
 	tgbotapi "github.com/go-telegram-bot-api/telegram-bot-api"
 	"log"
 )
@@ -19,11 +20,22 @@ func (rm RoutineManager) StartUpdates() {
 
 	for update := range updates {
 
-		group, err := rm.GroupHelperService.GetGroupByID(update.Message.Chat.ID)
+		var group *models.Group
+		var err error
+		if update.Message != nil {
+			group, err = rm.GroupHelperService.GetGroupByID(update.Message.Chat.ID)
 
-		if err != nil {
-			log.Println(err)
-			continue
+			if err != nil {
+				log.Println(err)
+				continue
+			}
+		} else if update.CallbackQuery != nil {
+			group, err = rm.GroupHelperService.GetGroupByID(update.CallbackQuery.Message.Chat.ID)
+
+			if err != nil {
+				log.Println(err)
+				continue
+			}
 		}
 
 		for _, routine := range rm.Routine {
diff --git a/telegram/routines/joinchecker.go b/telegram/routines/joinchecker.go
new file mode 100644
index 0000000..de713e4
--- /dev/null
+++ b/telegram/routines/joinchecker.go
@@ -0,0 +1,68 @@
+package routines
+
+import (
+	"git.dragon-labs.de/alphyron/group_helper/models"
+	"git.dragon-labs.de/alphyron/group_helper/telegram"
+	"git.dragon-labs.de/alphyron/group_helper/util"
+	tgbotapi "github.com/go-telegram-bot-api/telegram-bot-api"
+	"log"
+	"math/rand"
+	"strconv"
+	"time"
+)
+
+type joinCheckerRoutine struct {
+}
+
+func NewJoinCheckerRoutine() telegram.Routine {
+	return joinCheckerRoutine{}
+}
+
+func (j joinCheckerRoutine) Update(botAPI *tgbotapi.BotAPI, update *tgbotapi.Update, group *models.Group) error {
+
+	if update.Message == nil { // ignore any non-Message Updates
+		return nil
+	}
+
+	if update.Message.Chat.IsPrivate() || update.Message.Chat.IsChannel() {
+		return nil
+	}
+
+	if update.Message.NewChatMembers != nil {
+		for _, newUser := range *update.Message.NewChatMembers {
+			type check struct {
+				Task     string
+				Solution bool
+			}
+
+			length := 3
+
+			tasks := make([][]tgbotapi.InlineKeyboardButton, length)
+
+			for i := 0; i < length; i++ {
+				tasks[i] = tgbotapi.NewInlineKeyboardRow(tgbotapi.NewInlineKeyboardButtonData(util.GenerateCalculation(i == 0), "UserValidation: "+strconv.FormatBool(i == 0)))
+			}
+
+			rand.Seed(time.Now().UnixNano())
+			rand.Shuffle(len(tasks), func(i, j int) { tasks[i], tasks[j] = tasks[j], tasks[i] })
+
+			markup := tgbotapi.NewInlineKeyboardMarkup(tasks...)
+
+			msg := tgbotapi.NewMessage(update.Message.Chat.ID, group.UserJoinMessage)
+			//TODO Replace placeholder
+			msg.ParseMode = "Markdown"
+			msg.ReplyMarkup = markup
+
+			_, err := botAPI.Send(msg)
+
+			if err != nil {
+				log.Println("Problem to send verified Messages to user")
+				log.Println(newUser.FirstName)
+				log.Println(err)
+			}
+
+			//TODO Add to countdown
+		}
+	}
+	return nil
+}
diff --git a/util/calculator.go b/util/calculator.go
new file mode 100644
index 0000000..9d3d709
--- /dev/null
+++ b/util/calculator.go
@@ -0,0 +1,19 @@
+package util
+
+import (
+	"fmt"
+	"math/rand"
+)
+
+func GenerateCalculation(correct bool) string {
+	firstNum := rand.Intn(100)
+	secondNum := rand.Intn(100)
+
+	solution := firstNum + secondNum
+
+	for !correct && solution == firstNum+secondNum {
+		solution = rand.Intn(150)
+	}
+
+	return fmt.Sprintf("%d + %d = %d", firstNum, secondNum, solution)
+}