• install apache
• sudo apt-get install ruby1.8-dev
• sudo gem install passenger
• sudo passenger-install-apache2-module
• follow the instructions

Manually: configure a vhost in /etc/apache2/sites-available and link it to /etc/apache2/sites-enabled with something like the following
^
NameVirtualHost *:80

<VirtualHost *:80>
        ServerName application.local
        DocumentRoot /opt/application/public
        RailsEnv development
        RailsAllowModRewrite off
</VirtualHost>

<VirtualHost *:443>
        ServerName application.local
        DocumentRoot /opt/application/public
        RailsEnv development
        RailsAllowModRewrite off

        SSLEngine on
        SSLCertificateFile /etc/apache2/ssl/localhost.crt
        SSLCertificateKeyFile /etc/apache2/ssl/localhost.key
</VirtualHost>

• register the host in /etc/hosts or just connect to http://localhost/
• restart Apache or call touch tmp/restart.txt in your project root

SSL

• link /etc/apache2/mods-available/ssl.load and /etc/apache2/mods-available/ssl.conf into /etc/apache2/mods-enabled using sudo a2enmod ssl
• activate SSL in the vhost (like above)
• see this guide on how to self-sign an ssl certificate Show archive.org snapshot

Rails Long Term Support

Rails LTS provides security patches for old versions of Ruby on Rails (2.3, 3.2, 4.2 and 5.2)

• Prevents you from data breaches and liability risks
• Upgrade at your own pace
• Works with modern Rubies

Read more Show archive.org snapshot