I want to be able to access local dev server at local.djinni.co instead of using localhost:8000. You can plug any domain name into via /etc/hosts but using default http port (80) requires some trickery. I used default Apache server with virtual hosts support.

apache reverse proxy setup for mac os x

# enable Apache
sudo launchctl load -w /System/Library/LaunchDaemons/org.apache.httpd.plist

# Vim /private/etc/apache2/httpd.conf
# Enable Virtual Hosts Include

# Vim /private/etc/apache2/extra/httpd-vhosts.conf
<VirtualHost *:80>
    ProxyPreserveHost On

    ServerName local.djinni.co

    <Location />
        ProxyPass http://localhost:8000/
        ProxyPassReverse http://localhost:8000/
        Order allow,deny
        Allow from all
    </Location>
</VirtualHost>

# Vim /etc/hosts
127.0.0.1   localhost local.djinni.co