So how does this extension stack up in my list of things that make a good extension?
- Clear use case? Check.
- Sound technical approach? We believe so.
- A commitment to implementation by multiple implementers? In progress...
If this experiment is successful, it proves both the technical approach and the commitment to implementation. At that point, the SWG will be ready to adopt the new extension.
 The ongoing work is available at: https://github.com/opengeospatial/geopackage-elevation
 As with any other extension, if a client does not conform with it, it will not see the elevation data but it will be able to see the features and tiles as it always has.
 See the Activity Plan