ExpressJS is described as 'Framework for browser applications in nodeJS' and is an app in the development category. There are more than 50 alternatives to ExpressJS for a variety of platforms, including Linux, Mac, Windows, Self-Hosted solutions and Node.JS. The best alternative is Meteor, which is both free and Open Source. Other great apps like ExpressJS are Nest, AdonisJS, Crow and Koa.
Crow is a C++ microframework for running web services. It uses routing similar to Python's Flask which makes it easy to use. It is also extremely fast, beating multiple existing C++ frameworks as well as non C++ frameworks.
Expressive middleware for node.js using generators via co to make web applications and APIs more enjoyable to write. Koa's middleware flow in a stack-like manner allowing you to perform actions downstream, then filter and manipulate the response upstream.
Ractive.js is a template-driven UI library that transforms your templates, styles and logic into blueprints for highly interactive apps. Ractive.js works for you, not the other way around. You do not need to learn new terminologies, concepts, and methodologies.