Make sure you can easily route requests for a particular version to a different back-end server. If you in the future decide to write the next version of your

Make sure you can easily route requests for a particular version to a different back-end server. If you in the future decide to write the next version of your webservice using a different technology (e.g. going from python to node.js or whatever), you want your front-end server (e.g. nginx) to direct the traffic to the correct back-end without too much trouble.