Cloudflare is a web-infrastructure and website-security company, providing content-delivery-network services, DDoS mitigation, Internet security, and distributed domain-name-server services.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Klaviyo is an email marketing platform for online businesses.
Leaflet is the open-source JavaScript library for mobile-friendly interactive maps.
Netlify providers hosting and server-less backend services for web applications and static websites.
Open Graph is a protocol that is used to integrate any web page into the social graph.
Typekit is an online service which offers a subscription library of fonts.
Unpkg is a content delivery network for everything on npm.