Katton

ServerPlayerEvent.onPlayerJoin += join@ fun(arg: PlayerArg) {
    val player = arg.player
    val firstSeen = once(key = "welcome:${player.uuid}", namespace = "event_player_lifecycle_demo") {}

    if (firstSeen) {
        tell(player, "[event-demo] Welcome to the server! Enjoy your stay! ")
    } else {
        tell(player, "[event-demo] Welcome back!")
    }
}