Not much different to getting CGI working. If you need it working well, FastCGI is as much effort as PHP-fpm. SUexec is as much effort as SUPHP.
Any language could supplant PHP in terms of ease of deployment, there's little out there that doesn't have some CGI library to handle the mucky parts.
Not that I am advocating use of CGI for anything non-trivial.
Not much different to getting CGI working. If you need it working well, FastCGI is as much effort as PHP-fpm. SUexec is as much effort as SUPHP.
Any language could supplant PHP in terms of ease of deployment, there's little out there that doesn't have some CGI library to handle the mucky parts.
Not that I am advocating use of CGI for anything non-trivial.