https://github.com/technion/mod_randpad https://github.com/technion/mod_randpad (an Nginx module that injects padding as a comment into returned HTML documents)

https://github.com/technion/mod_randpad https://github.com/technion/mod_randpad (an Nginx module that injects padding as a comment into returned HTML documents) is likely the correct layer to add random padding; the performance hit would be negligible.