1. The Planet has stopped updating because I moved the cron entry from /etc/cron.daily/ to /etc/cron.d/. The latter doesn't work for some reason, and with systemd and all these cron directories, I can't figure out how to read the logs from the cronjobs. (We are running stock Debian with the cron and systemd configuration that comes with it.)
If any Linux wizard wants to take a look via ssh, that would be appreciated.
2. Our aggregator software, Planet Venus, is once again showing its age. It does indeed get the right feed URL for Chicken Gazette, but on the Planet's sidebar, clicking on "Chicken Gazette" tries to take you to the URL "tag:gazette.call-cc.org,2010-08-29:/". The aggregator gets this URL from the Atom feed's <id>...</id> tag.
3. For some reason, Planet Venus turns spritely.institute's URL into "https://spritely.institute/spritely.institute", i.e. it duplicates the hostname. I suspect this may have something to do with it not recognizing that ".institute" is a top-level domain, but I don't know for sure. The feed URL is correct in planet.ini.