paths

.htaccess

<IfModule mod_rewrite.c>
    RewriteEngine On

    # Client Reroutes
    RewriteBase /web/
    RewriteRule ^web\/index\.php$ - [L]

    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteRule . /web/index.php [L]
 </IfModule>

folder_structure

/src
  index.js
/web
  .htaccess
  index.php

index.js

import m from 'mithril';
import { Layout } from 'views/Layout';
import { Index } from 'views/Index';

m.route.prefix('/web');

m.route(document.getElementById('app'), '/', {
    '/': {
        render () {
            return (
                <Layout>
                    <Index />
                </Layout>
            );
        }
    }
});