Kamal — Deploy web apps anywhere

Whether that’s low-cost cloud options without the managed-service markup from the likes of Digital Ocean, Hetzner, OVH, etc, or it’s your own colocated bare metal. To Kamal, it’s all the same. Feed the config file a list of IP addresses with vanilla Ubuntu servers that have seen no prep beyond an added SSH key, and you’ll be running in literally minutes.

Kamal basically is Capistrano for Containers, without the need to carefully prepare servers in advance. No need to ensure that the servers have just the right version of Ruby or other dependencies you need. That all lives in the Docker image now. You can boot a brand new Ubuntu (or whatever) server, add it to the list of servers in Kamal, and it’ll be auto-provisioned with Docker, and run right away. Docker’s layer caching also speeds up deployments with less mucking about on the server. And the images built for Kamal can be used for CI or later introspection.

Kubernetes is a beast. Running it yourself on your own hardware is not for the faint of heart. It’s a fine option if you want to run on someone else’s platform, either transparently like Render or explicitly on AWS/GCP, but if you’d like the freedom to move between cloud and your own hardware, or even mix the two, Kamal is much simpler. You can see everything that’s going on, it’s just basic Docker commands being called.