Rails 8 ships with Kamal 2 pre-configured, enabling zero downtime deployments to any Linux server without a PaaS. Kamal 2 replaces Traefik with a purpose-built Kamal Proxy that handles automatic SSL via Let's Encrypt, supports multiple apps on one server, and drains in-flight requests during container swaps. New Rails 8 apps get a ready-to-use config/deploy.yml, a production Dockerfile, and a .kamal/secrets file out of the box. Key features covered include improved secrets management with password manager integration, command aliases, fast rollbacks via container switching, and multi-tenant SSL options including Caddy for wildcard certificates. Kamal 2 pairs with Solid Queue, Solid Cache, and Solid Cable to run a full production stack on a single server.
