gatsby

Gatsby is a free and open-source web framework based on React, released under the MIT license and distributed on npm as the `gatsby` package. According to its README, it aims to combine the control and scalability of dynamically rendered sites with the speed of static-site generation, helping developers build performant, content-rich websites and apps. **Data layer** Gatsby can pull content from any data source: Markdown files, headless CMS systems such as Contentful or WordPress, or REST and GraphQL APIs. Source plugins load the data, and developers then work against a uniform GraphQL interface regardless of the backend. **Rendering options** The project documents three rendering approaches that can be selected on a per-page basis: Static Site Generation (SSG), Deferred Static Generation (DSG) and Server-Side Rendering (SSR). The README presents this granularity as a way to trade off performance and productivity per page rather than globally. **Beyond static sites** Gatsby sites are described as fully functional React apps, so the same framework can serve blogs, e-commerce sites and user dashboards. Because output is static, sites can be hosted on a CDN without a server, and the README notes many sites can be hosted free on Netlify and similar services. **Performance features** The README states that Gatsby automates code splitting, image optimization, inlining of critical styles, lazy-loading and prefetching of resources, so that performance tuning is largely built in rather than manual. **Getting started** Two quick paths are documented. Online: a "Deploy to Netlify" button creates a working site plus a linked repository that automatically rebuilds on push. Locally: run `npm init gatsby` to scaffold a project, then `cd my-gatsby-site/` and `npm run develop` to start a development server at `http://localhost:8000` with live updates when files such as `src/pages/index.js` are edited. Separate quickstart, tutorial, plugin, starter and showcase pages are linked from the top of the README. **Documentation and community** The README points to an in-depth tutorial that assumes no prior level of ability, plus documentation sections for how-to guides, reference material and conceptual guides. Release notes and per-version support documentation are linked, and migration guides cover upgrading from v2 to v3, v3 to v4 and v4 to v5. A code of conduct and a contributing guide are provided, and the repository is organized as a Lerna-managed monorepo containing multiple packages that are published to npm separately. Issues, discussions and pull requests are part of the community workflow described.