I use plain text accounting for my business, and it's lovely to be able to enter bookkeeping data with a plain text editor and keep it all under version control, but the next step is using a program such as hledger or beancount to work with that data.
I'd love to work with plain text calendar software, but it would still need to do things such as provide a mechanism to work on my desktop and mobile device. It would need to handle recurring events automatically, and it would need to allow me to invite others to events and ideally to track when they've accepted or rejected my invites.
I'd need to be able to update, cancel or propose to move events in such a way that others would be updated.
I wish I knew of a good command line tool to interact with CalDav or similar servers, or that I could maintain my calendar in a file format and then handle the synchronization automatically.
Maybe calendar.txt could play a role in that, but on its own, it's not quite enough for me.
There is a task equivalent, which also supports caldav sync
I use calendar.txt on a cell phone with Markor text editor. For my desktop, I just use micro editor on terminal, the same I use for most text editing tasks.
Bookkeeping using plain text files sounds both interesting and challenging.
It has quite a bit of a following; I personally would never switch back to some more "complete" application. I believe all the most popular implementations are listed here: https://plaintextaccounting.org/
This tools is a successor to vdirsyncer, which filled a similar role but with several limitations.
I’ve working in Pimsync for many months now. The basics all work fine, but still working in some extended feature. Feedback is most welcome at this stage.
The Unix philosophy is often recited as "do one thing, and do it well". This does one thing, but doesn't do it well at all.
It's conflating a format for recording calendars with a syntax the user needs to write.
That syntax looks quite brittle and not very intuitive. One day = one line would get unwieldy fast. It doesn't localise well and there's no obvious way to implement recurring events beyond daily actions. (From what I can see at least?)
You could build a client on top of that but then, you lose the benefit.
It's a neat idea and it's good to see someone share a simple concept that works for them. But I don't see it working for most people.
> Unix philosophy. It's one day, one line. You can grep (only show lines).
Surprisingly, grep is able to output several lines, so even if you were to use a (say) more sensible format of one line per event, grep could still output all lines, and display them.
## 2025-02-27 W09 Thursday
- Team standup
- Looking up flights to Venus
- Meeting with Acme
- Discuss hydrocoptic marzlevanes
- TODO: read up on them <http://example.com/docs/hydrocoptic-marzlevanes>
- (personal) Feed the dragon
- #5934 Fix glitch in dingle arm reciprocator
The vim macro I use is:
" Macro To Do Today
nmap mtdt <esc>O<CR><esc>k"=strftime('## %F W%V %A')<CR>Pa<CR><CR>-Most of my notes are write-only for a day or so but I keep the old ones around just in case I need to grep through everything (and I've saved myself doing this a few times).
function notes {
THIS_MONTH="$(date '+%Y-%m')"
mkdir -p "$NOTES_FOLDER/$THIS_MONTH" # create folder if it doesn't exist.
cd "$NOTES_FOLDER/$THIS_MONTH"
if [ -z "$1" ]; then
return 0
fi
vim $1
cd -
}
It sounds super dumb but it works so well.
The main feature is that I can categorize the events (personal, family, work, friends, etc.) and share individual URL’s with other people. Admitedly, I didn’t try solving this problem with Google Calendar, Apple Calendar, or any other calendar service, mostly because I wanted to own my data and also learn a bit more about CalDav itself.
https://www.neilvandyke.org/todotxt/
In some ways it worked well, but there were a few drawbacks, and eventually I switched to native calendar programs on desktop and mobile.
Drawbacks I personally felt:
* In the text file, recurring tasks didn't show up when I looked into the future, such as to schedule an appointment.
* Calendar invites over email weren't integrated, so I had to enter and update those manually anyway. (Though one advantage over the native calendar programs I use now is that todo.txt doesn't force the appointment headline someone else wrote into my calendar view, and refuse to let me edit it in my local copy.)
* I had to keep editing dates on tasks manually, every day, for my "current day view" of top of the file to work with priorities.
* No visual calendar views with the tools I was using.
* No device sync with the tools I was using (though possible).
* There are only so many ways in which I was willing to be a weirdo at once, and this one didn't make the cut.
I don't discourage anyone from trying todo.txt or calendar.txt. Just a heads-up of some things you might want to find solutions/workarounds for.
Use calendar.txt format and method with the following changes:
1) Use markdown, with a top level heading of Calendar (so inclusion is easier) and the portion
2) Use :tag: instead of +tag. Tags can be run together (:tag:tag2:). This helps with Org mode compatibility
3) Third level heading for each event in day, following same format as calendar.txt
4) text under heading is for notes about the event
5) Searching and seeing info on event in day, or summary about day is no longer easy with grep. This is the biggest drawback from not using calendar.txt. Overcome by writing a tool mgrep that is specifically designed to search markdown files in a Markdown aware way (search headings or specific level of headings, show all headings under matching heading or just one level under, show all content under matching headings, search text and show either lines or section text is in optionally along with ancestry of headings).
6) Create CalendarMDMode, minor mode designed to facilitate calendar.md use and editing within Emacs, requires OrgMode, things like shortcuts for new date, new event, in-editor use of mgrep, etc.
7) Attempt to add CalendarMD support to Helix, which is my daily notes editor, using the as-yet unlanded Scheme based plugin system (see https://github.com/helix-editor/helix/pull/8675 )
* [ ] YYYY-MM-DD
* [ ] 1800: Dinner with parents
* [x] Walk the dog
* [ ] YYYY-MM-DD
* [ ] 0900: Interview new recruit
* [ ] Prepare interview questions
* [ ] Upload result to HR system
These days I have a little A6 lined notebook and manually list tasks there. Each page is a new day and the tasks are listed similarly. The only modification is that sometimes I put some letters to theme a task, i.e.:
* [ ] YYYY-MM-DD
* [x] Home: Walk the dogI think my approach would be to generate a file in Markdown, then import that into a good Markdown editor. You could generate it each week or month from a template, making it easier to add repeating tasks like exercise and dog walking.
For me the best parts are:
1. You could write a parser very quickly.
2. It's very easy to edit and add to as a human.
3. It can easily be tracked in git or via a diff-based tool.
I did already think about the repetitive tasks, a long time ago I used to have a tool that would look at the past tasks and recommend future tasks (with appropriate distributions). One example was booking a dentist appointment every 6 months, even if I forgot to schedule something it would remind me to book one in, dismiss it or push it back.
Periodically my task system fails (the Taskwarrior 3 disaster being the most recent) and this is pretty much what I end up using. But then I forget a bill or something important because there are no bells or buzzers keeping me as a useful working unit. Then I erect the previous system, or some variant, and go with that until some inevitable breakage sends me back to paper. So it goes...
Although, TBH, the OP's suggestion of one-line-per-day puts too many items on the same ling. I would have gone with one line per event. Yes, there's more repetition, but you need no out-of-line context, you have to do a lot less parsing, and you can look at a fixed number of _columns_ and get the beginning of the description of each event, which is nicer for manual searching.
I think that it's far more important that it is human readable, if it becomes too tricky to edit manually, then just go with a database.
Also: claims to be "one thing per line", yet allows and encourages multiple events on one line (as long as they're on the same day). This is a calendar - is an event not the main "thing" we're dealing with?!
In my work, similar events happen on the same week numbers in different years. The importance of week numbers probably depends on your area of work.
For me, one thing is a day. That's also the context I need when reviewing and planning. But if I remember correctly, previous HN thread on calendar.txt had a suggestion where someone had an event-per-line format, if you prefer that.
[1] https://terokarvinen.com/2021/calendar-txt/calendar-txt-unti...
https://www.gnu.org/software/emacs/manual/html_node/emacs/Fo...
There are a few more structured formats for calendaring that share the virtues of their workflows: if we used JSON, would jq be a UNIXy tool? What about sqllite and commandline queries? Both would be much more easier for my overloaded mind - especially when parsing records - without adding more inherent complexity beyond a sufficiently overloaded raw text calendar.
Anyone who knows me will tell you I am not very organized. Possibly this is why.
Android support is definitely substandard, even with Termux.
It's not foolproof. On one occasion I typed in the month wrong, though in the right place in the file. When I noticed that the line was out of order, I moved it to where the date said it should be. Arriving a month late, I discovered that the studio space I'd paid for no longer existed.
My text calendar management script is still available here: https://code.up8.edu/pablo/myutils/-/blob/master/kal
There might be value in checking that out.
Personally I haven't used it in years, but the latest release is from this year so it seems active.
The details of how I had it all wired up are now lost to memory, but it seemed to accomplish a similar goal to calendar.txt while supporting standard calendar file formats and sync with Google Calendar.
- No extra app needed
- Keeps them quite hidden / private / secure
- Always easy access (I always have emails open)
- In sync with different devices
> Keeps them quite hidden / private / secure
Not hidden from Google obviously :) At that point, why not just use Keep at that point to get proper support for notes?
Works with all file formats, from photos and movies to text files. Cross platform: Linux, Windows, Android, probably also Mac and BSD.
Update: And it's end-to-end encrypted and free, open-source software.
I suspect the experience is better on Android.
https://github.com/syncthing/syncthing-android --- "Discontinued This app is discontinued. The last release on Github and F-Droid will happen with the December 2024 Syncthing version."
It would be cool if there were a crash course on this stuff, but even that wouldn't work well, because the first time you use a unixy system, it would be too much information to retain, and subsequent times you're likely to just gloss over all this stuff.
Perhaps the only real solution is asking about what you want to do on messages boards, and hoping some weird old curmudgeon who is familiar with the small program you want to use sees your question.
I installed it just to read the man page: """
LANG=C
Easter=Ostern
#include <calendar.usholiday>
#include <calendar.birthday>
6/15\tJune 15 (if ambiguous, will default to month/day).
Jun. 15\tJune 15.
15 June\tJune 15.
Thursday\tEvery Thursday.
June\tEvery June 1st.
15 *\t15th of every month.
May Sun+2\tsecond Sunday in May (Muttertag)
04/SunLast\tlast Sunday in April,
\tsummer time in Europe
Easter\tEaster
Ostern-2\tGood Friday (2 days before Easter)
Paskha\tOrthodox Easter
It worked far better than expected. The only thing missed was age calculations for birthdays. I never figured that out. Using the Emacs Diary provided that sort of thing though.
I've since moved to KDE Kontact for mail/calendaring. It works more smoothly if you do a lot of calendar sharing with others, but I could see going back to nail(1)/calendar(1) if Kontact disappoints.
I'm an AI curmudgeon in general but this is a place where LLMs really excel. You ask "how do I do x thing I want to do" and it either tells you, from the morass of docs it knows about, or it hallucinates and you find out ten seconds later when there's no man page for the command -- and then you fall back to traditional methods.
Either the LLM gives you a discoverability shortcut, or you're back where you started, anyway.
For example, I recently scheduled a dentist appointment 6 months from now. Unless I scroll through the calendar, or specifically search for it, there is no easy way to find that I added that event.
One main benefit from git is also to work as an insurance against (user) errors, and make the whole process much more transparent. When I have used calendars with automatic synchronization, I would have enjoyed a "change log" to make sure that my timezones and meetings are not mistakenly modified by software.
For your dentist example, I would probably just use 'grep' or find in my text editor. After all, six months of days is very little text.
Using a full stop as a separator seems rather limiting, something less likely to appear in an event description such as a vertical pipe would make more sense. Now you'd need some kind of weird logic to write an event titled "read top 10 news.ycombinator.com articles". Using @ as a special character also means you can't store "email support@localhost.com" as an event title.
And, of course, everything is hard coded in English, using English style time notation.
This seems like a fine solution for a personal file format but everyone will probably have to modify it to fit their own needs. If I were to use it, I'd violate the "spec" all over the place by time and date notation alone. This could be fixed by adding some kind of header, but I doubt any full application will ever support a format like this so it's hardly a problem.
If I were to use this as a file format, I'd add headers to store things like language, default time zone, ltr vs rtl, and alter the separator characters. Adding something like a title, an author, and the moment of last edit might also be useful.
I'd personally also probably store events as separate, duplicate lines. That way, you can easily add an event to the bottom of the file without having to find/replace an existing date (or generate an entirely new line). Using basic POSIX tools you can easily get the events back to a single line without making scripts too difficult to read. Assuming culture and other headers match, you'd be able to import another calendar file by simply appending the event lines.
Calendar.txt is indeed a personal calendar. So feel free to violate the spec as much as you need or want to. My main use for calendar.txt is editing with text editor, and thus, I have not given emphasis to automatic modification.
Time notation is ISO-8601 date and week number. In my view, ISO-8601 is an international standard and not tied to a specific country. I find it convenient to read and sort.
I use local time for physical events. For international calls, I just write down the timezone "13:00Z" or "11:00EET" (update: or mark it in my local time).
At-sign "@" for context was chosen to match todo.txt, as I also use that. As the calendar is personal, it does not need to be fully machine readble. But for your example on email addresses, you could still do it: @WORK email bob@example.com. The context starts with an at "@", email does not.
Full stop "." is easy to type on a cell phone. It's true that a rare char would be more suitable for automatic parsing.
Thanks for the ideas!
If you want to follow UNIX philosophy, why don't you write an augmenter/converter tool `caug` that adds "computed" information such as week number, weekday or even relative date?
> cat calendar-src.txt
2025
====
03-01 9-12 project groups
> cat calendar-src.txt | caug
2025-03-01 w09 09:00-12:00 project groups +tomorrow
+thisweek
> cat calendar-src.txt | caug | grep "thisweek"
2025-03-01 w09 09:00-12:00 project groups +tomorrow
+thisweekWith some traditional GUI calendar software, I was often hunting and miscopying week numbers. Some software also had a weird (non ISO-8601) idea of week numbers.
In case you need calendar.txt after 2033, I wrote a small tool [2] to generate more templates.
[1] https://terokarvinen.com/2021/calendar-txt/calendar-txt-unti...
[2] https://terokarvinen.com/2021/calendar-txt/calendartxt-gener...
usage: weeks YYYY-MM-DD YYYY-MM-DD
weeks () {
one_day=$((60 * 60 * 24))
unix_from=$(date +%s --date="$1")
unix_to=$(date +%s --date="$2")
while [ $unix_from -lt $unix_to ]
do
echo @$unix_from
unix_from=$((unix_from + one_day))
done | date +'%F w%V %a' -f -
unset -v one_day unix_from unix_to
}
- one line per event, so good luck finding multi-day events like “Grandma is visiting”;
- rigid metadata (dates, week numbers, weekdays) stored right next to the editable data (events), so copy-pasting errors are inevitable;
- the most important feature of the real calendar software (reminders) is thrown out;
- grepping is really not how most people interact with a calendar.
If you’re ready to ditch reminders, attachments, locations, use the paper diary planner. At least it won’t let you screw the dates with botched copy-paste.
Update: also, sorting by date must be done manually, my god.
The format allows for variable granularity and ranges. If Grandma were visiting for a week, it would be fine:
2021-02-20 w07
2012-02-20 w07 Mon-Fri Grandma is visiting
I don't think the creator ever suggested for one minute that this is a calendar for "most people"! Most people don't use Linux, macOS, or a command line.
> sorting by date must be done manually, my god.
| sort
I use +plustags for multiday and recurring events. So for each line +grandma is visiting, I would add the tag +grandma.
I take similar approach with my courses, +tt for pentesting (from the word in Finnish). I found that for me, creating and validating recurring and multiday events was easier for me. Of course, your mileage may vary.
Smikhanov, you found copy pasting challenging. For me, copy pasting from some dedicated calendar software was a challenge. Copy-pasting with calendar .txt makes it easier for me to keep date, week number, weekday and the event together. And your comment on paper planners was on the spot, I wanted to catch some of their benefits, transparency and reliability with calendar.txt.
I believe software is a form of literacy, not engineering. And I believe everyone should be literate it brings great benefits socially and individually
And if this works for him/her it’s a calendar on a piece of paper stuck to the fridge. Great, it works for them and some people might find it good for them too
But yeah.
“One day I will get organisssseed”
This is what I do for todos and reminders, with a few index cards binder-clipped together with a tiny pen. I use [0]; its size is right but it’s just a ballpoint refill that isn’t particularly great. Using it makes me miss my typical fine-tip gel pens. Anybody else use this kind of system and have a tiny pen to recommend?
It also works nicely together with calendar.txt for me. I can 'grep' trough both to see all todos and events related to a project or a +tag.
His response was WOAH, I've always wanted this! He then send the whole thing to the printer and put it on the wall in his office. Then he added arrows to the days he forgot to pay using a ballpoint pen. He talked a bit about periods in the year and used his finger as a pointing device.
3 days ago, 7 points, 0 comments https://news.ycombinator.com/item?id=43169019
1004 days ago, 202 points, 93 comments https://news.ycombinator.com/item?id=31574125
With that in mind I don't see how this is a replacement for caldav. Sure looking at the plain text of a caldav file is worse, especially one generated by a computer, but at least all expected calendar functionality is included. Though the sprawling RFC is hardly simple to follow or implement.
I just create files in a folder with the `yyyy-MM-dd-hh:mm` format. I use `XX` for recurring events.
I use `at` for reminders/notifications.
The point of calendars is to align with other people’s lives
It's like this, but better. I actually get notifications from my calendar text file. I can set some of them as alarms.
https://web.archive.org/web/20250216110151/https://terokarvi...
`YY-MM-DD:HH:MMa (Optional repeat cron definition) "Event string"`
Editing this on mobile sounds very annoying.
[1] https://terokarvinen.com/2021/calendar-txt/calendartxt-gener...
[2] https://terokarvinen.com/2024/format-date-calendar-txt/dateg...
[2] https://terokarvinen.com/2024/format-date-calendar-txt/
Update: Added the template until 2400.