Eleventy is a simple static site generator with flexible templating and zero client-side JavaScript. It handles zero config, multiple templates, data cascade, and plugins, and it's best suited for developers wanting a simple, zero-config static site generator. It has been around since 2018, giving it a 8-year head start in building out integrations and refining the product.

The core product is entirely free. Since it's open-source, you can self-host for free with no user limits. It's aimed at individual users, so it's fast to set up but may lack team-management features if you scale.