Thanks all for your input. It's a bit buffling that calendars are not a solved problem in 2021. Going down the path of vdirsyncer + davmail with some self written filters to only show blockers (stripped everything else out) seems to be the most sensible way.

I have to, on a regular basis actually and I'm glad gdb and FPC work well together.

Nice to hear, I have a pascal lisp project I need to revive, having gdb on my side would help

That's awesome! They taught Pascal in my CS undergrad classes.

related post on lwn: https://lwn.net/Articles/591723/