Railway has introduced a new feature called "Scale to Zero" which allows users to automatically stop and start workloads with no traffic, including databases, with the flip of a switch. This feature is made possible by leveraging Envoy proxies, namespaces, nftables, and cAdvisor to monitor and manage traffic. When a container is inactive for 5 minutes, it will be flagged as such and stopped, but its port will remain active, allowing traffic to be redirected to the container when it becomes active again. This feature aims to reduce downtime and improve scalability for users, with benefits ranging from cost savings for indiehackers to improved efficiency for Fortune 500 companies. The feature is now available in Priority Boarding, and users can toggle the "App Sleeping" setting to enable or disable it.