Google Font API is a web service that supports open-source font files that can be used on your web designs.
Google Hosted Libraries is a stable, reliable, high-speed, globally available content distribution network for the most popular, open-source JavaScript libraries.
HTTP Strict Transport Security (HSTS) informs browsers that the site should only be accessed using HTTPS.
Leaflet is the open-source JavaScript library for mobile-friendly interactive maps.
Mapbox GL JS is a JavaScript library that uses WebGL to render interactive maps from vector tiles and Mapbox styles.
Mapbox.js is a JavaScript library provided by Mapbox for working with interactive maps and geospatial data.
Progressive Web Apps (PWAs) are web apps built and enhanced with modern APIs to deliver enhanced capabilities, reliability, and installability while reaching anyone, anywhere, on any device, all with a single codebase.
Ruby on Rails is a server-side web application framework written in Ruby under the MIT License.
Sentry is an open-source platform for workflow productivity, aggregating errors from across the stack in real time.
A modest JavaScript framework for the HTML you already have.