Besides ReactJS and its ecosystem libraries, I'm experimenting with Elm for some time now.

Other than that:

• Koa.js
• express
• Angular 2 is something I will definitely try when it's officially released.
• Aurelia is getting attention in the last couple of months and the feedback from the community is really good. I'll be following their progress and may eventually use it in a project of my own.

For testing:

• mocha, chai, sinon.JS
• tape
• heard a lot of good things about ava, so I will probably give it a try.

Usually EmberJS , sometimes React, sometimes without any frameworks .

None, I work mostly in Dart, have written my own framework for past projects and have just started using Angular Dart 2 for a new project.

I just grepped through my projects and here are my most used dependencies (besides React.js, Redux and Router):

• https://ava.li/ - Futuristic test runner + https://github.com/substack/tape - tap-producing test harness for node and browsers
  • https://github.com/mjackson/expect - Write better assertions
• https://www.browsersync.io/ - Time-saving synchronised browser testing
• http://koajs.com - Next generation web framework for Node.js, designed by the team behind Express.js
• http://momentjs.com/ - Parse, validate, manipulate, and display dates in JavaScript.
• http://yeticss.com/ - &yet's lightweight, modular pattern library written in Stylus.

• Server side: Express, Koa, Restify, LoopBack
• Client side: RactiveJS, Riot.js , T3.js, Aurelia
• Test: Mocha, Karma, Jasmine, Protractor

For unit testing I use, Mocha, chai and sinon.