If a project of yours still runs on version 3, now is a good time to migrate to Serverless Framework v4, sooner rather than later. Version 3 has not received security updates or bug fixes since early 2025. Even so, many teams keep postponing the switch because they expect trouble with licensing, sign-in and build plugins. That worry is understandable, but mostly overblown.

The Serverless Framework has been my favorite tool for Lambda-heavy backends for years. That is why I use a small example from a fictional city library to show you how the move from v3 to v4 works: from the license question and the new sign-in all the way to the CI pipeline. You also get the typical pitfalls, including the error messages, so you recognize them before they cost you a Friday afternoon.

In short

For AWS projects, switching to Serverless Framework v4 is manageable: update the CLI, sign in, replace build plugins with the built-in esbuild and give your pipeline an access key or license key.…