Are new `.js` ui frameworks and - libs a fad?

Good question! TL-DR: Most are, except: jQuery React vue.js Frameworks - not for me! In web UI, frameworks like BackBone, Ember and Angular might be all nice and stuff, but when you start using them to compose larger applications, things tend to break down quite easily with less experienced developers. Developing large client-side applications requires the same modelling skillset as developing large server-side applications; the complexity is usually not located in the infrastructure, but in properly mapping boundaries and responsibilities within your solution space.