Sails.js (is based on ExpressJS) is a great for creating APIs, saves a lot of time if you're doing a MVP or testing something, and you can use a package to integrate PassaportJS which will give you the ability to use OAUTH2 well integrated to the framework.
I always use Sails when I doing an MVP or a simple API.
Here in Rio de Janeiro (Brazil), they saves lives. People are afraid to go out to drink driving and lost the car (with stay with the police) and the driver's license (1-year without the license and have to go through all the classes to get the license again) plus a fine of R$1,915.65(around US$980).
It works here, a lot of people are preferring a cab over the car to go out to places they know they will drink.
I always use Sails when I doing an MVP or a simple API.