function recordWin(uint winner_index, uint amount) internal {
        if(recentWins.length < recentWinsCount) {
            recentWins.length++;
        } else {
            
            
            for(uint i = 0; i < recentWinsCount - 1; ++i) {
                recentWins[i] = recentWins[i + 1];
            }
        }

        recentWins[recentWins.length - 1] = Win(contributors[winner_index], block.timestamp, contributions[winner_index], amount);
    }