Getting "* server can't find pinboard.in: NXDOMAIN" via multiple networks and https://dnschecker.org/#A/pinboard.in is currently showing that it's not resolving anywhere in the world. Did Maciej forget to renew it?
I use it on a tiny cloud instance and refresh the feeds at regular intervals with cron. This lets me tune out from the news cycle for days or even weeks at a time. When I have to appear like I've not been living under a rock, I can catch up fairly quickly.
A useful tool and great UI work. A handy extension would be the ability to extract text of specific colour, e.g. the highlights in Kindle's Cloud Reader, to get around the 10% highlight export cap that Amazon puts on most books. I did this previously by running the screenshot through ImageMagick's colour filling and thresholding options before passing the output to Tesseract. A colour picker tool might be a nice addition.