Although several frameworks promise the same ease of development and scalability typical of static site generators, we continue to have good experiences with Gatsby.js. In particular we've used it to build and deploy websites that scale to very large numbers of users without having to worry about capacity planning or deployment infrastructure. Our developers have also been impressed by the focus on accessibility and support for old browsers and that they could reuse their React.js experience. All in all, we feel Gatsby has matured well and is a solid choice in this space.
Gatsby.js is a framework to write web applications in an architectural style known as JAMstack. Part of the application is generated at build time and deployed as a static site, while the remainder of the functionality is implemented as a progressive web application (PWA) running in the browser. Such applications work without code running on the server side. Usually, though, the PWA makes calls to third-party APIs and SaaS solutions for content management, for example. In the case of Gatsby.js, all client and build time code is written using React. The framework includes some optimizations to make the web application feel fast. It provides code and data splitting out of the box to minimize load times and speeds up performance when navigating the application by prefetching resources. APIs are called via GraphQL and several plugins simplify integration with existing services.