The Calibre2opds source code has been migrated to gitHub as the Google Code site which has served us well for some time is going to be closed down later this year. As we are just about to start development for the 3.5 release now seems an appropriate time to do this migration rather then perhaps being forced to do it in the middle of the development for the 35 release.
This means that the 3.4 release is the last one hosted on Google Code. It will be available in read-mode for some time, but if you want to get the latest code you will have to go to the new gitHub repository.
There will be a short period where the online documentation has not been updated to reflect this change. It will be updated appropriately as experience is gained in working with gitHub.
EDIT: The changes to use gitHub seem to be less than anticipated, so the changes to the online documentation were minimal and should now be complete.
It is possible that it might also be appropriate to migrate the handling of issues and feature requests to gitHub to keep things in one place and to provide integration between versioning and issue resolution. However no decision has yet been made on this area.