Used technologies: MeteorJs, ReactJs, NodeJs, Bootstrap, react-Bootstrap. How you can see, the whole Web application created with separate modules. Each modules include his own dependencies and can easily be used in other projects. I don't use RequireJs, because I work with MeteorJs which allow me to work with NodeJs using ES6 syntaxes.

module-example.jsx

/* Import variables ***************************************************************************************************/
import React from 'react';
import ReactDOM from 'react-dom';
import {composeWithTracker} from 'react-komposer';
import {Modal, Button} from 'react-bootstrap';

import './deposit.css';

/* React components ***************************************************************************************************/
const Deposit = (props) => {
    inputAmount = () => {
        let amount = (Math.round(((+document.getElementById('form-input').value + 0.3) / 0.961) * 100) / 100).toFixed(2);
        let customAmount = document.getElementById('form-input').value;
        document.getElementById('customAmount').value = customAmount;
        document.getElementById('PayPal-input').value = amount;
        document.getElementById('totalCost').innerHTML = amount;
    };
    return (
        <div className="Modal">
            <Modal show={props.show} onHide={props.deposit} className="Modal-content">
                <Modal.Header>
                    <Modal.Title className="container-fluid bg-primary">
                        пополнение баланса
                    </Modal.Title>
                </Modal.Header>
                <form
                    className="modal-form"
                    action="https://www.paypal.com/cgi-bin/webscr"
                    method="post"
                    target="_top">
                    <Modal.Body>
                        <div>
                            <h5>Комиссия PayPal 4% + 0.30$ в не зависимости от суммы пополнения.</h5>
                            <div className="input-group">
                                <div className="input-group">
                                    <span className="input-group-addon">$</span>
                                    <input onInput={this.inputAmount}
                                           id="form-input"
                                           name="form-amount" type="number" step={0} min={2}
                                           className="form-control"
                                           placeholder="минимум 2$"/>
                                    <input type="hidden" id="PayPal-input" name="amount" step={0} min={2}/>
                                </div>
                                <h5 style={{textAlign: 'right'}}>к оплате: <span id="totalCost">0.00</span>$</h5>
                                <input type="hidden" name="cmd" value="_xclick"/>
                                <input type="hidden" name="business" value="[email protected]"/>
                                <input type="hidden" name="item_name" value="lottato balance refill"/>
                                <input type="hidden" name="charset" value="utf-8"/>
                                <input type="hidden" name="currency_code" value="USD"/>
                                <input type="hidden" name="notify_url" value="http://lottato.com/ipn"/>
                                <input type="hidden" name="return" value="http://lottato.com/success"/>
                                <input type="hidden" name="cancel_return" value="http://lottato.com/cancel"/>
                                <input type="hidden" name="custom" value={props.userId}/>
                                <input type="hidden" name="item_number" id="customAmount"/>
                                <input type="hidden" name="lc" value="ru_RU"/>
                                <input type="hidden" name="no_note" value={1}/>
                                <input type="hidden" name="no_shipping" value={1}/>
                            </div>
                        </div>
                    </Modal.Body>
                    <Modal.Footer>
                        <a onClick={props.deposit}
                           type="button" className="btn col-xs-4 btn-danger modalClose" data-dismiss="modal">закрыть</a>
                        <a type="button" className="col-xs-4"/>
                        <input type="submit" className="btn col-xs-4 btn-primary" value="пополнить" name="submit"/>
                    </Modal.Footer>
                </form>
            </Modal>
        </div>
    );
};

/* Composer ***********************************************************************************************************/
const composer = (props, onData) => {
    const userId = Meteor.users.findOne({_id: Meteor.userId()})._id;
    onData(null, {userId});
};

/* Export variables ***************************************************************************************************/
export default composeWithTracker(composer)(Deposit);