Command-line and Emacs Calendar Client
1- [x] list/search events
2- [x] add/remove events
3- [x] edit events
4- [x] timezones
5- [ ] allow editting recurrence-ids
6- [ ] really stress test the timezone handling -- this is full of gotcha's
7- [ ] don't load all calendars into memory to show only one event
8- [ ] support specifying duration
9- [ ] diagnose events failing to parse
10 - [[https://github.com/robur-coop/icalendar/issues/14]]
11- [ ] [[https://github.com/robur-coop/icalendar/pull/13][handle RECURRENCE-ID]]
12- [ ] [[https://github.com/robur-coop/icalendar/issues/15][RRULE with local datetime]]
13- [ ] CalDAV syncing
14 - Currently, you can use [[https://github.com/pimutils/vdirsyncer][vdirsyncer]]
15- [ ] support querying times as well as dates
16- [ ] custom date/time formatting
17- [ ] support querying regex
18- [ ] support VTIMEZONE
19- [ ] support VALARMS
20- [ ] support VOTODS
21- [ ] support VCARDS
22- [ ] server mode
23 - and maybe hold =Event='s in-memory in a =Collection= instead of parsing them for every =Query=
24- [ ] implement TUI front end with something like [[https://github.com/leostera/minttea][minttea]]
25- [ ] implement an emacs client like mu4e
26- [ ] parallel queries
27- [ ] remove collection module
28 - ref [[https://github.com/ocaml-ppx/ppxlib/issues/481]] cc patrick