Improve error messages in hooks

**Feature request**
It would be great to have serialization for middleware.

**Use case**
Many users need this functionality for production deployments.

**Implementation idea**
Add a new config option `enable_serialization` with default `false`.

No files or tests are named in the issue. Start by locating the middleware configuration and the existing hook or serialization entry points, then trace how production configuration is loaded. Done means an `enable_serialization` option exists, defaults to `false`, and middleware serialization is covered by an appropriate test.

Written by the indexing model from the issue text.