With registration email command

UserService.kt

fun create(user: User): User {
        return withinTransaction {
            val savedUser = userRepository.save(user)
            eventsEngine.send(UserCreated(UUID.randomUUID().toString(), user))
            eventsEngine.send(SendRegistrationEmailEvent(UUID.randomUUID().toString(), user))
            User.create(savedUser)
        }
    }