Node is single-threaded by default, so you'll need to work on it. In the other hand, Node is better because you are already working with JavaScript as Frontend developer. Also, all you need is to make a prototype and Node is great for building simple API prototypes so I think the best way would be: make a nodejs prototype and test it - you'll get numbers with which you can work later. Take a look at Artillery.io and Mocha for testing. After that you can ask for someone's help in rewriting some endpoints or even make a separate api endpoint using another framework / language. Nginx would be helpful in this.