The framework(s) I always look to learn or recommend learning are the ones that I think are going to be big in 5 years.<p>Of course, consider front-end or back-end first, but I&#x27;ll assume you are open to either.<p>I&#x27;m currently learning Play (scala) because the framework is a part of two projects I&#x27;ve been involved with at my current job.<p>I was learning Mercury.js because we selected it for a project, mostly because I wasn&#x27;t a fan of Flux, but having said that, the community has voted for React, so I&#x27;ll be moving to get more experience with React (we&#x27;re not re-writing the Mercury stuff, but I probably won&#x27;t recommend it for future projects, BUT, if you&#x27;re not familiar with Mercury.js, check it out, I really like it).<p>I&#x27;m assuming you&#x27;re already down either the Less or Sass road, so I&#x27;d look for the next thing in CSS, which just might be <a href="https:&#x2F;&#x2F;github.com&#x2F;css-modules&#x2F;css-modules" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;css-modules&#x2F;css-modules</a><p>For testing, I&#x27;d check out Tape (unit tests) and nightwatch.<p>Make sure you&#x27;re up on Webpack and&#x2F;or Browserify<p>Oh the list goes on and on.<p>Out of curiosity, you mention web development framework, but do you have any interest in IoT? and would you want to use your web-dev skills in interfacing with hardware? The reason I ask is I&#x27;ve been building a framework which hopefully will allow web-devs to develop embedded code. I&#x27;d be keen to hear your feedback.