Kamal 2.x

A lightning talk given at Slovenia Ruby User Group on 10th October 2024.

Transcript

1. Miha Rekar Lightning talk Kamal 2.x
2. Migration Expert • Last several blog posts all about migrations: • SES -> Postmark and (ab)using generates_token_for for List-Unsubscribe Headers • Pagy -> Turbo with in inite scrolling* • Devise to native Rails 8 Auth* • Fly.io to Hetzner with Kamal 2† *on Radan’s blog † WIP
3. ECT Business • https://business.europeancoffeetrip.com/ • Postgres DB • Small number of users • Café Awards • Huge traffic spike • Fly gets expensive real fast • How hard can it be?
5. All the metrics
6. Just add accessories • kamal accessory boot prometheus • kamal accessory boot node_exporter • kamal accessory boot cadvisor • kamal accessory boot grafana • Add a simple prometheus.yml
7. Hetzner • All in a single CAX11 ARM VM • 4f the RAM and 2f CPU of Fly • 1/8th the price • Response times slashed in half • No traffic bottlenecks (yet) • Much faster and zero-downtime deploys
8. Just Do It # • Already hosted a couple of tiny services • This gave me con idence • Visualizer next • What are you migrating? • 20× Hetzner credits $
9. Thank you!