Core Architecture
My calendar app is a static, multi-page application with a fixed release cycle (annual deployment). It features a hard-coded UI with immutable data — the dates and layout cannot be modified without manual intervention. It’s essentially a read-only interface optimized for offline-first functionality.
Key Features
Data Structure - 12-month dataset rendered as a grid-based layout with pre-populated date objects
State Management - Completely stateless; no persistent storage or sync capabilities
User Interaction - Supports reads and writes; compatible with any pen/pencil (similar to a POST request, but non-reversible)
Rendering - Raster-based output; responsive design (fits on my wall)
Accessibility - Physical accessibility for all members of my cohort
Portability - Take a picture once a month, refer to that on your phone
Performance - O(1) lookup time for any date; zero latency, zero network overhead
Technical Advantages
Zero dependencies, requires only wall space and a pen.
No API to support / learn, no loading times / lag, no version conflicts.
Guaranteed uptime. It’s also compliant with most privacy standards, though it does require physical access.
Limitations
The calendar has no real-time sync, no cross-device functionality, and no undo. Annotations are permanent with an ink pen. It cannot adjust for time zones or integrate with other calendar systems. No ICS compatible export of appointment data. And unfortunately, the application will need to be replaced after just one year.
If you’re interested in implementing a similar app, I can point you in the right direction…
Is this subscription model: daily, monthly, or yearly?
If I pay more for the “pro-lite” subscription will it include AI integration?
I’m so confused by this products pricing model - it seems so foreign. Without AI, I don’t see how you’ll be able to IPO and buy up all the other calendar companies. /s
no persistent storage
Doesn’t it have one-time copy-on-write persistent storage?
Performance - O(1) lookup time for any date
Going to need to see the math here. It’s March, explain the O(1) transition to view October 12th.
Yeah, this should be equivalent to interpolation search, which has an average performance of O(log(log(n))).
It helps that the months are separately indexed, so instead of a search on 365 input elements, you can do two searches with much lower input size, i.e. 12 and 31.
But yeah, you’re still in the larger O(log(log(n))) category with that.
Oh damn, I was afraid someone would ask about that. I just thought it sounded good.
If you have tabs for each month, it could be O(1) since it requires only one flip.
Constant: 12 months. Beyond this year? Error 404
Nice humble brag there: “paid”
Sorry I can’t read your README.md since its lacking any emojis. I’m sure its a nice project but I can’t tell if its blazing fast or not
Not only is it blazing fast, it’s also opinionated.
Oh wow, what’s the opine API?
Is this self-hosted?
If you have a magnet you can deploy it on any bare-metal.
It does work better on some, than on others though.
Due to the omission of the year number on the grid, it’s somewhat reusable too. 2037 is the next time all the dates and days of the week will match.
Ah, another oppurtunity to bring up international fixed calendar that could reuse the calendar every year!
I feel like proponents of that calendar might be better off giving all the months completely different names. It would avoid some of the potential confusion during the changeover. Sol could keep its name, I guess, but the rest, no.
On the other hand, that still wouldn’t disambiguate numeric YYYY-MM-DD and the like.
That’s a good point, months would need new names. And dates should have some other format, maybe a F prefix: FYYYY-MM-DD
Continue waving that around if you want to get murdered by every programmer in the world simultaneously.
And renters. That extra month rent gonna be real unpopular.
It would be the same annual amount but spread over 13 months, right?
Right?
If the landlord isn’t the scummy type…
Does anyone know what that painting with the little sailboat is called? Or was it made for the calendar? I like it.
Plug the pic into reverse image search, it’s returning a bunch of results for me. Although it’s mostly greeting cards, and cropped compared to the OP image.
E.g. ‘Boat on Lake at Night’.
The calendar is generic Japanese style art, they don’t give any credits.
But since you asked, the sailboat painting reminds me a little Henri Rousseau.
I can’t believe I forgot to say:
My calendar app will make the world a better place through decentralized uncompressed data parsing and sharing.
I may have just watched all six seasons of Silicon Valley.
Dang, these e-ink displays are getting really good these days
Do you plan on adding any + subscription features?
Don’t forget about AI. We need AI in every part of our lives /s
Reasonable yearly fee that helps the developer keep maintenance
I like the size of the display
Have you tried unpinning it, and then pinning it back in?
And if that doesn’t work, try folding and unfolding.
Bug report: shows April when it’s March.
Why is the text all blurry?
… no undo…
Have you thought about adding the erasable pen libraries?
But can it run Doom?
