Support caching configuration

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

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

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

No file, test, or entry point is named. Start by locating the configuration parsing and route-handling entry points, then trace how route data is currently handled. Done means a new `enable_serialization` option defaults to `false` and enables route serialization when set to `true`.

Written by the indexing model from the issue text.