The funny thing is the response time is quite good despite running it through a NodeJS server that launches a PHP binary (340ms, faster than 98% of the sites as per pingdom[1]).
[1] https://tools.pingdom.com/#!/ex9izm/https://www.lambdaphp.ho...
340ms is not a good response time at all. You need to elevate your expectations.
How much do you reckon we can get the response time with these optimizations? Right now the 340ms is nodejs + php-cli + my wrapper script (that inits s3, etc) + the actual content script (another php file) and request for the css framework from a CDN.
It's not persistent in that it exists between requests, but for the use case here it's exactly what is needed. He would save significant response time by having php-fpm already running, code parsed, opcodes cached and just issuing a new FCGI request to php-fpm instead of relaunching the PHP CLI each and every time.