Your-Deployments-Are-Stuck-in-the-Past-The-Lost-Art-of-the-Hot-Restart

The author of the article recounts a past experience where a simple version update turned into a disaster, highlighting the need for a better way to handle deployments. The author notes that the term "maintenance window" was a fact of life in the past, where services had to be paused, files replaced, and everything hoped to go smoothly. The author describes this approach as a "high-stakes gamble" where the outcome was uncertain. As technology evolved, tools like Shell scripts, process managers, and containerization were introduced to improve deployment, but they still fell short of achieving seamless, zero-downtime updates. The author discusses the limitations of using external tools like PM2 and systemd, which, although powerful, are not perfect solutions due to their external dependency, language or ecosystem lock-in, and "black box" operation. The author then introduces the concept of internalizing service management as part of the application, using a Rust library called server-manager, which allows the application to manage itself. This approach brings several benefits, including code as configuration, lifecycle hooks, and cross-platform compatibility. The author highlights the importance of achieving zero-downtime hot restarts, which can be accomplished by internalizing the update logic into the application. This involves receiving a restart signal, executing a pre-restart hook, compiling a new version, and handing over sovereignty to the new process. The author concludes that deployment should be a confident declaration, not a prayer, and that the Rust ecosystem has provided a new, more reliable philosophy of building and maintaining software. The author emphasizes the need for better tools and a more composed development experience, marking a shift away from the "wild west" of the past and towards a new era of deployment. The article ultimately advocates for a more elegant and reliable approach to deployment, one that is integrated into the application itself.