We can write the frontend code in the following languages: JavaScript, HTML5, CSS3, Vue.js, Angular, React, Next js, Redux, TypeScript, Mob-x, Graph ql, Svelte, Gatsby js, Single Page Applications (SPA), LESS, PostCSS, RequireJS, ES6 Modules, Webpack, Gulp, Google Closure Compiler, jQuery, Backbone.js, REST, WebSockets, SVG, Google Web Toolkit (GWT), Bootstrap.