Bootstrap is a free and open-source CSS framework directed at responsive, mobile-first front-end web development. It contains CSS and JavaScript-based design templates for typography, forms, buttons, navigation, and other interface components.
JSDelivr is a free public CDN for open-source projects. It can serve web files directly from the npm registry and GitHub repositories without any configuration.
Plausible is an open-source alternative to Google Analytics.
Vimeo is a video hosting, sharing and services platform. Vimeo operation an ad-free basis by providing subscription plans.