Isomorphism.md

So What's the Big Deal About Running Serverside Javascript Anyways

"Isomorphism", in web development, is a word that has come to describe applications that run a majority of their code on both the server and client. The most obvious benefit of developing an application that way is that you can write your code once- not twice, if you had a split-language application. Libraries for API access, validation, template rendering (and the templates themselves) are all shared and testable in any environment.

In reddit-mobile's case, that means having, essentially, a client.js file and a server.js file that each mount the same application code. We've chosen libraries specificially for their sharability, and we use the same transpiler ([[babel|ECMAScript]]) on both sides.

There is a limited amount of code that only runs in one stack, outside of client.js and server.js, which is intentionally kept to a minimum:

• For error logging, context.env is checked in app-mixin. This ensures that server-side errors display that the error occured on the server, rather than on a browser.
• The API library snoode checks options.env to determine whether or not it should use cached API responses - the server should not cache, but the client does.