index.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Chess Board</title>

    <!--
        The HTML part of your standard set of things to add in order to get 
        the app to fill the entire page. 
    -->
    <style>
        * {
            padding: 0;
            margin: 0;
        }
    </style>


</head>
<body>
    <!-- The following is important for building the part of the socket that 
    can send messages to the server. -->
    <script src="/socket.io/socket.io.js"></script>
    <script src="https://code.jquery.com/jquery-3.4.1.min.js"></script>
    
    <script src="https://pixijs.download/v7.0.4/pixi.min.js"></script>

    <!-- 
        The entire chess engine, split into modules by closure, loaded 
        in order. Into the same namespace. 
    -->
    <script src="chess_engine_mbc/debug.js"></script>

    <script src="chess_engine_mbc/test_boards.js"></script>
    <script src="chess_engine_mbc/utilities_and_reference.js"></script>
    <script src="chess_engine_mbc/mutables_initializers.js"></script> 
    <script src="chess_engine_mbc/blocking_functions.js"></script>    
    <script src="chess_engine_mbc/king_threat_functions.js"></script>
    <script src="chess_engine_mbc/movement_options_functions.js"></script>
    <script src="chess_engine_mbc/engine_index.js"></script>

    <script src="./app.js"></script>
</body>
</html>