ReactQL is a React + GraphQL front-end starter kit. #JSX is a natural way to think about building UI, and it renders to pure #HTML in the browser and on the server, making it trivial to build server-rendered Single Page Apps. GraphQL via Apollo was chosen for the data layer; #GraphQL makes it simple to request just the data your app needs, and #Apollo takes care of communicating with your API (written in any language; doesn't have to be JavaScript!), caching, and rendering to #React.
ReactQL is written in TypeScript to provide full types/Intellisense, and pick up hard-to-diagnose goofs that might later show up at runtime. React makes heavy use of Webpack 4 to handle transforming your code to an optimised client-side bundle, and in throws back just enough code needed for the initial render, while seamlessly handling import statements asynchronously as needed, making the payload your user downloads ultimately much smaller than trying to do it by hand.
React Helmet was chosen to handle <head> content, because it works universally, making it easy to throw back the correct <title> and other tags on the initial render, as well as inject new tags for subsequent client-side views.
styled-components, Sass, Less and PostCSS were added to give developers a choice of whether to build styles purely in React / JavaScript, or whether to defer to a #css #preprocessor. This is especially useful for interop with UI frameworks like Bootstrap, Semantic UI, Foundation, etc - ReactQL lets you mix and match #css and renders to both a static .css file during bundling as well as generates per-page <style> tags when using #StyledComponents.
React Router handles routing, because it works both on the server and in the client. ReactQL customises it further by capturing non-200 responses on the server, redirecting or throwing back custom 404 pages as needed.
Koa is the web server that handles all incoming HTTP requests, because it's fast (TTFB < 5ms, even after fully rendering React), and its natively #async, making it easy to async/await inside routes and middleware.