16 JavaScript frameworks developers should learn in 2019

JavaScript web development frameworks

React

React was first developed by Facebook in 2011 and then open sourced in 2013. Since then it has become one of the most popular JavaScript libraries for building user interfaces. According to npm’s survey, despite a slowdown in React’s growth in 2018, it will be the dominant framework in 2019. The State of JavaScript 2018 survey designates it as “a safe technology to adopt” given its high usage satisfaction ratio and a large user base.

In 2018, the React team released versions from 16.3 to 16.7 with some major updates. These updates included new lifecycle methods, Context API, suspense for code splitting, a React Profiler, Create React App 2.0, and more. The team has already laid out its plan for 2019 and will soon be releasing one of the most awaited feature, Hooks. It allows developers to access features such as state without using JavaScript classes. It aims to simplify the code for React components by allowing developers to reuse stateful logic without making any changes to the component hierarchy. Other features will include a concurrent mode to allow component tree rendering without blocking the main thread, suspense for data fetching, and more.

Vue

Vue was created by Evan You after working for Google using AngularJS in a number of projects. It was first released in 2014. Sharing his motivation for creating Vue, Evan said, "I figured, what if I could just extract the part that I really liked about Angular and build something really lightweight."  Vue has continued to show great adoption among JavaScript developers and I doubt this trend is going to stop anytime soon. According to the npm survey, some developers prefer Vue over React because they feel that it is “easier to get started with, while maintaining extensibility.”

Vue is a library that allows developers to build interactive web interfaces. It provides data-reactive components, similar to React, with a simple and flexible API. Unlike React or Angular, one of the benefits of Vue is the clean HTML output it produces. Other JavaScript libraries tend to leave the HTML scattered with extra attributes and classes in the code, whereas Vue removes these to produce clean, semantic output. It provides advanced feature such as routing, state management, and build tooling for complex applications via officially maintained supporting libraries and packages.

Angular

Google developed AngularJS in 2009 and released its first version in 2012. Since then it saw enthusiastic support and widespread adoption among both enterprises and individuals. AngularJS was originally developed for designers, not developers. While it did saw a few evolutionary improvements in its design, they were not enough to fulfill developer requirements. The later versions, Angular 2, Angular 4, and so on have been upgraded to provide an overall improvement in performance, especially in speed and dependency injection.

The new version is simply called Angular, a platform and framework that allows developers to build client applications in HTML and TypeScript. It comes with declarative templates, dependency injection, end to end tooling, and integrated best practices to solve development challenges. While the architecture of AngularJS is based on model-view-controller (MVC) design, Angular has a component-based architecture. Every Angular application consists of at least one component known as the root component. Each component is associated to a class that’s responsible for handling the business logic and a template that represents the view layer.

Node.js

There has been a lot of debate around whether Node is a framework (it’s really a library), but when talking about web development it is very hard to skip it. Node.js was originally written by Ryan Dahl, which he demonstrated at the the inaugural European JSConf on November 8, 2009. Node.js is an free, open-source, cross-platform JavaScript run-time environment that executes JavaScript code outside of a browser.

Node.js follows a "JavaScript everywhere" paradigm by unifying web application development around a single programming language, rather than different languages for server side and client side scripts. At the JSConf 2018, Dahl described some limitations about his server-side JavaScript runtime engine. Many parts of its architecture suffer from limitations including security and how modules are managed. As a solution to this he introduced a new software project, called Deno, a secure TypeScript runtime on V8 JavaScript engine that sets out to correct some of the design flaws in Node.js.  

Cross-platform mobile development frameworks

React Native

The story of React Native started in the summer of 2013 as Facebook’s internal hackathon project and it was later open sourced in 2015. React Native is a JavaScript framework used to build native mobile applications. As you might have already guessed from its name, React Native is based on React, that we discussed earlier. The reason why it is called “native” is that the UI built with React Native consists of native UI widgets that look and feel consistent with the apps you built using native languages.

Under the hood, React Native translates your UI definition written in Javascript/JSX into a hierarchy of native views correct for the target platform. For example, if we are building an iOS app, it will translate the Text primitive to a native iOS UIView, and in Android, it will result with a native TextView. So, even though we are writing a JavaScript application, we do not get a web app embedded inside the shell of a mobile one. We are getting a “real native app”.

NativeScript

NativeScript was developed by Telerik (a subsidiary of Progress) and first released in 2014. It’s an open source framework that helps you build apps using JavaScript or any other language that transpiles to JavaScript, for example, TypeScript. It directly supports the Angular framework and supports the Vue framework via a community-developed plugin. Mobile applications built with NativeScript result in fully native apps, which use the same APIs as if they were developed in Xcode or Android Studio.

Since the applications are built in JavaScript there is a need for some proxy mechanism to translate JavaScript code to the corresponding native APIs. This is done by the runtime parts of NativeScript, which act as a “bridge” between the JavaScript and the native world (Android and iOS). The runtimes facilitate calling APIs in the Android and iOS frameworks using JavaScript code. To do that JavaScript Virtual Machines are used – Google’s V8 for Android and WebKit’s JavaScriptCore implementation distributed with iOS 7.0+.

Ionic Framework

The Ionic framework was created by Drifty Co. and initially released in 2013. It is an open source, frontend SDK for developing hybrid mobile apps with familiar web technologies such as HTML5, CSS, and JavaScript. With Ionic, you will be able to build and deploy apps that work across multiple platforms, such as native iOS, Android, desktop, and the web as a Progressive Web App.

Ionic is mainly focused on an application’s look and feel, or the UI interaction. This tells us that it’s not meant to replace Cordova or your favorite JavaScript framework. In fact, it still needs a native wrapper like Cordova to run your app as a mobile app. It uses these wrappers to gain access to host operating systems features such as Camera, GPS, Flashlight, etc. Ionic apps run in low-level browser shell like UIWebView in iOS or WebView in Android, which is wrapped by tools like Cordova/PhoneGap.

JavaScript Desktop application development frameworks

Electron

Electron was created by Cheng Zao, a software engineer at GitHub. It was initially released in 2013 as Atom Shell and then was renamed to Electron in 2015. Electron enables web developers to use their existing knowledge and native developers to build one codebase and ship it for each platform separately. There are many popular apps that are build with Electron including Slack, Skype for Linux, Simplenote, and Visual Studio Code, among others.

An Electron app consists of three components: Chromium web engine, a Node.js interpreter, and your application’s source code. The Chromium web engine is responsible for rendering the UI. The Node.js interpreter executes JavaScript and provides your app access to OS features that are not available to the Chromium engine such as filesystem access, networking, native desktop functions, etc. The application’s source code is usually a combination of JavaScript, HTML, and CSS.

JavaScript Machine learning frameworks

Tensorflow.js

At the TensorFlow Dev Summit 2018, Google announced the JavaScript implementation of TensorFlow, their machine learning framework, called TensorFlow.js. It is the successor of deeplearn.js, which was released in August 2017, and is now named as TensorFlow.js Core. The team recently released Node.js bindings for TensorFlow, so now the same JavaScript code will work on both the browser and Node.js.

Tensorflow.js consists of four layers, namely the WebGL API for GPU-supported numerical operations, the web browser for user interactions, and two APIs: Core and Layers. The low-level Core API corresponds to the former deeplearn.js library, which provides hardware-accelerated linear algebra operations and an eager API for automatic differentiation. The higher-level Layers API is used to build machine-learning models on top of Core. It also allow developers to import models previously trained in Python with Keras or TensorFlow SavedModels and use it for inference or transfer learning in the browser.

Brain.js

Brain.js is a library of neural network written in JavaScript, a continuation of the “brain” library, which can be used with Node.js or in the browser. It simplifies the process of creating and training a neural network by utilizing the ease-of-use of JavaScript and by limiting the API to just a few method calls and options. It comes with different types of networks for different tasks, which include a feedforward neural network with backpropagation, time step recurrent neural network, time step long short term memory neural network, among others.

JavaScript augmented reality and virtual reality frameworks

React 360

In 2017, Facebook and Oculus together introduced React VR, which was revamped and rebranded last year as React 360. This improved version simplifies UI layout in 3D space and is faster than React VR. Built on top of React, which we discussed earlier, React 360 is a JavaScript library that enables developers to create 3D and VR interfaces. It allows web developers to use familiar tools and concepts to create immersive 360 experiences on the web.

An application built with React 360 consists of two pieces, namely, your React application and runtime, which turns your components into 3D elements on the screen. This “division of roles” concept is similar to React Native. As web browsers are single-threaded, the app code is separated from the rendering code to avoid any blocking behavior in the app. By running the app code in a separate context, the rendering loop is allowed to consistently update at a high frame rate.

AR.js

AR.js was developed by Jerome Etienne in 2017 with the aim of implementing augmented reality efficiently on the web. It currently gives efficiency of 60fps, which is not bad for an open source web-based solution. The library was inspired by projects like three.js, ARToolKit 5, emscripten and Chromium.

AR.js requires WebGL, a 3D graphics API for the HTML5 Canvas element, and WebRTC, a set of browser APIs and protocols that allow for real-time communications of audio, video, and data in web browsers and native apps. Leveraging features in ARToolKit and A-Frame, AR.js makes the development of AR for the web a straightforward process that can be implemented by novice coders.

New and emerging JavaScript frameworks

Gatsby.js

The creator of Gatsby, Kyle Mathews, quit his startup job in 2017 and started focusing full-time on his side projects: Gatsby.js and Typography.js. Gatsby.js was initially released in 2015 and its first version came out in 2017. It is a modern site generator for React.js, which means everything in Gatsby is built using components. With Gatsby, you can create both dynamic and static websites/web apps ranging from simple blogs, e-commerce websites to user dashboards.

Gatsby supports many database sources such as Markdown files, a headless CMS like Contentful or WordPress, or a REST or GraphQL API, which you can consolidate via GraphQL. It also makes things like code splitting, image optimization, inlining critical styles, lazy-loading, and prefetching resources easier by automating them.

Next.js

Next.js was created by ZEIT and open sourced in 2016. Built on top of React, Webpack, and Babel, Next.js is a small JavaScript framework that enables an easy server-side rendering of React applications. It provides features like automatic code splitting, simple client-side routing, Webpack-based dev environment which supports HMR, and more. It aims to help developers write an isomorphic React application, so that the same rendering logic can be used for both client-side and server-side rendering.

Next.js basically allows you to write a React app, with the SSR and things like code splitting being taken care of for you. It supports two server-side rendering modes: on demand and static export. On demand rendering means for each request, a unique page is rendered. This property is great for web apps that are highly dynamic, in which content changes often, have a login state, and similar use cases. This mode requires having a Node.js server running. While static export on other hand renders all pages to .html files up-front and serves them using any file server. This mode does not require a Node.js server running and the HTML can run anywhere.

Nuxt.js

Nuxt.js was originally created by the Chopin brothers, Alexandre and Sébastien Chopin and released in 2016. In January 2018, it was updated to a production-ready 1.0 version and is backed by an active and well-supported community. It is a higher-level framework inspired by Next.js, which builds on top of the Vue.js ecosystem and simplifies the development of universal or single page Vue.js applications.

Under the hood, Nuxt.js uses webpack with vue-loader and babel-loader to bundle, code-split and minify your code. One of the perks of using Nuxt,js is that it provides a nuxt generate command, which generates a completely static version of your Vue application using the same codebase. In addition to that, it provides features for the development between the client side and the server side such as Asynchronous Data, Middleware, Layouts, etc.

NestJS

NestJS was created by Kamil Mysliwiec and released in 2017. It is a framework for effortlessly building efficient, reliable, and scalable Node.js server-side applications. It builds on top of TypeScript and JavaScript (ES6, ES7, ES8) and is heavily inspired by Angular as both use a Module/Component system that allows for reusability.

Under the hood, NestJS uses Express, and is also compatible with a wide range of other libraries, for example, Fastify. For most of its abstractions, it uses classes and leverages the benefits of decorators and metadata reflection that classes and TypeScript bring. It comes with concepts like guards, pipes, and interceptors, and built-in support for other transports like WebSockets and gRPC.

These were some of my picks from the plethora of JavaScript frameworks. You surely don't have to be an expert in all of them. Play with them, read the documentation, get an overview of their features. Before you start using a framework you can check it for few things such as the problems it solve, any other frameworks which do the same things better, if it aligns with your project requirement, which type of projects would this framework be ideal for, etc. If that framework appeals to you, maybe try to build a project with one.

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