I have a Rails app that makes heavy use of the `created_at` and `updated_at` fields. 

I've found that something like `Post.last.created_at.to_f` will give me epoch time but I always need epoch time so I was wondering if there is some way to write an automated post-query filter that will do the conversion every time I called `created_at` and `update_at`. Right now, every time I read `created_at`/`updated_at` I repeat myself, which is bad form, and has already caused bugs when I forget to do the conversion. 

I'm using Rails 3.2.13 and Ruby 1.9.3p392.

Also, I can't just write `post.created_at.to_f` in my view since I'm using render JSON for my output.