my $public_html = "$ENV{HOME}/Sites"; # OS X
use CGI::Emulate::PSGI;
CGI::Emulate::PSGI->handler(sub {
    die "Forbidden" if $ENV{PATH_INFO} =~ /\.\./;
    my $f = "$public_html/$ENV{PATH_INFO}";
    if ($f =~ /\.cgi$/ && -e $f && -f _) {
        do $f;
        CGI::initialize_globals if defined &CGI::initialize_globals;
    } else {
        print "Content-Type: text/html\n\n404 Not Found";
    }
});