As the ruby application loads in memory at startup and then is executed from there (in production) there is no need of bytecode caching, in contrast with PHP wh

As the ruby application loads in memory at startup and then is executed from there (in production) there is no need of bytecode caching, in contrast with PHP where the code is read, parsed and interpreted on each request, and in this (second) case, caching the bytecode to save parsing execution makes sense. That is the case of bytecode caching. In regards to other forms of caching (etag, memoization etc) frameworks implement different strategies.