In my freelancing career I usually choose the language with the following Q&A to my colleagues ( myself, if it's a side project ). 1. Are there business requir

In my freelancing career I usually choose the language with the following Q&A to my colleagues ( myself, if it's a side project ). 1. Are there business requirements for the language ( already written project, specs, etc. ) ? 2. What kind of budget does the company has for hiring devs ( killing point for Clojure, Elixir, TypeScript, etc. ) ? 3. What's the most difficult problem that needs to be solved by the product ( you probably don't want to create a 3D Game with NodeJS, right? Or a highly dynamic charting with PHP ) ? 4. Is there going to be a front-end / back-end division in the team ( Having a division makes you more comfortable in choosing the back-end language, since most full-stack devs are using NodeJS/PHP/Ruby ) ? 5. Finally if you are working on your own task and previous questions didn't give you the right answer, you could ask yourself : Do I need to learn something new or I want to build something fast? At this point you will have eliminated most of the obvious choices. Recently I'm using Isomorphic TypeScript with NodeJS for most of my side-projects, but first thing I will do if something goes above a certain amount of users is to start thinking business-wise and answer those questions on my own.