Ask HN: How do you decide for a backend language?

I'm "only" 6 years into my career but already worked with a dozen languages. While there are some obvious distinctions (like elixir being a better fit for concurrent systems or some being statically typed while some are not), most of them are very similar.

For corporate projects I usually comply to whatever language the system is already written in and adapt to that, but if I were to start a new project now, I wouldn't be sure which language is the right choice.

Here are some of the languages I used for projects in the past:

- Go

- Clojure

- Elixir

- Ruby

- Python

- Java

- NodeJS

- PHP / Hack

How are you deciding which language to pick when starting from scratch?

(On a similar note, the same thing could be asked for client side code: JS, TypeScript, ClojureScript, PureScript, ES6 / Babel, Coffee, etc)