https://github.com/noreastergroup/coldwire-rails

We build Rails apps and needed one to work with no network - our client’s users are out on islands off the Maine coast with no cell service. Hotwire doesn’t ship with anything for this, and a naive service worker breaks once Turbo is handling navigation. So we built a service worker plus precache manifest, a fallback page Turbo will actually render, and a settings screen where users can force a sync before heading out and inspect what’s cached. It’s been in production for a while, so we extracted it into a gem.