Built an open-source Nepali calendar API that computes dates astronomically

Natural-Sympathy-195 · 2026-04-05T01:52:50+00:00

Makes sense. I’ll keep an eye on it as you push further into calendar systems.

Natural-Sympathy-195 · 2026-04-05T01:39:02+00:00

the problem is real. ephemeral chat decisions are genuinely one of the failure modes nobody talks about with AI-assisted development. you end up with a codebase that works and a chat history nobody will ever read again, and the gap between them is where bugs live six months later.

the role separation is interesting. my question is where you've found the overhead actually worth it vs. where it creates more friction than the undocumented decisions it prevents. an Architect-to-Manager-to-Developer handoff works well for large teams or async work, but on a solo project or a fast prototype it feels like it could slow you down faster than the problem it solves. curious if you've run this on projects of different scales and where the crossover is.

one thing i'd push on: "A Developer works solely from files, without chat context or inherited assumptions" is a strong constraint. sometimes the chat context IS the decision, especially when the reasoning behind a constraint is nuanced. files that capture the WHAT without the WHY are just a different version of the original problem.

the license split makes sense technically. practically, most people won't distinguish between methodology and scaffold in daily use, so i'd make sure the docs are very explicit about what falls under which license at the point where someone would actually care.

minor note: the opener about "not as a growth strategy, that's simply the right thing to do" is going to read as performative to a lot of engineers here. you don't need to justify releasing open source. just release it.

Natural-Sympathy-195 · 2026-04-05T01:30:12+00:00

the ML loss function analogy actually maps pretty well, same situation where you're hoping for a clean closed-form and end up humbled by something that's been empirically refined over millennia

on optimization, the interesting thing is the performance profile is probably the opposite of what you'd expect. a single ephemeris call for planetary position is microseconds. computing an entire year of festival dates is maybe 50-100ms total on a single thread, which is already fast enough that caching is the main lever worth pulling, not parallelism. i do precompute festival dates on first request per year and cache them, so repeat calls are essentially free.

the batch case is real though. if someone hits `/calendar/range?start=2080&end=2200` you want multiprocessing there, and python's embarrassingly parallel story is fine for that since each date is fully independent. standard ProcessPoolExecutor handles it cleanly.

the GPU clustering angle is interesting for your image augmentation case but would be fighting the wrong bottleneck here. the nutation series (1365 lunisolar terms) is dense polynomial evaluation that maps well onto SSE/AVX on a single CPU core, not GPU parallelism. numpy already vectorizes most of it. the actual constraint for a calendar API is network I/O and cold start latency, not compute. throwing a GPU cluster at it would be like renting a cargo ship to deliver a letter.

what was the niche ML problem if you don't mind sharing? curious what the loss function was approximating

Natural-Sympathy-195 · 2026-04-05T01:23:53+00:00

Checked it out properly, and the reduction pipeline is genuinely impressive. A pure-Python stack built around DE441 plus explicit IAU 2000A/2006 reductions is, architecturally, a much more auditable approach than treating Swiss Ephemeris as a black box. For my use case, the real constraint is deployment economics more than mathematical taste. A multi-GB kernel footprint is a hard sell for a public API running on low-cost/free-tier infrastructure, whereas pyswisseph gives me a much lighter operational profile for the calendar range I actually need.

So yeah, the MIT route is definitely attractive, but I’d have to solve the infra tradeoff before it becomes a realistic foundation for Parva.

Still, this is absolutely the kind of project I want on my radar, and I can see it being very useful as a validation/reference engine even before it’s a direct backend candidate. If you push further into Vedic calendar systems, I’d be especially interested. Do you have BS sankranti computation on the roadmap?

Natural-Sympathy-195 · 2026-04-05T01:13:31+00:00

Natural-Sympathy-195 · 2026-04-04T09:10:48+00:00

clean scope. the fact that it does exactly one thing and you resisted the urge to add sync, a browser extension, tags, search, AI suggestions, and a premium tier means you actually understand the problem you were solving. and hmm JSON in appdata with no integrity check means one corrupt write and the user loses everything silently. worth adding a backup file that gets written before every save. second, 60% of your repo is HTML and 33% is TeX which tells me the actual Python is pretty thin, which is fine for a utility, but if PyQt is doing most of the heavy lifting you might want to understand the parts you didn't write before someone files a bug you can't debug.

good ship though. you built it because you needed it, you released it. most people stop before that second part.

Natural-Sympathy-195 · 2026-04-04T08:38:32+00:00

Computing a non-formulaic lunisolar calendar from first principles using ephemeris data

The Bikram Sambat calendar presents an interesting problem: month boundaries have no algebraic formula, only observable ones. You can derive them by computing sankranti (solar transit into each zodiac sign) and applying the traditional rule that a month begins the day after the Sun enters a new sign, conditioned on whether the crossing occurs before or after local sunrise.

Implemented this using Swiss Ephemeris with a fallback to lookup tables for the officially published range.

https://github.com/dantwoashim/Project_Parva

Natural-Sympathy-195 · 2026-04-04T08:37:44+00:00

honestly same, i did not sign up to learn this much about lunar angular distances when i started. dates are miserable enough in regular programming, adding "but which calendar system and also where is the sun right now" makes it a special kind of painful.

Natural-Sympathy-195 · 2026-04-04T08:35:02+00:00

Computing a non-formulaic lunisolar calendar from first principles using ephemeris data

The Bikram Sambat calendar presents an interesting problem: month boundaries have no algebraic formula, only observable ones. You can derive them by computing sankranti (solar transit into each zodiac sign) and applying the traditional rule that a month begins the day after the Sun enters a new sign, conditioned on whether the crossing occurs before or after local sunrise.

Implemented this using Swiss Ephemeris with a fallback to lookup tables for the officially published range.

https://github.com/dantwoashim/Project_Parva

Natural-Sympathy-195 · 2026-04-04T08:33:24+00:00

check now

Natural-Sympathy-195 · 2026-04-04T08:30:33+00:00

The API itself is something I’m building to keep stable long term, but the current public instance is still tied to hosted infrastructure limits, so if that host expires, sleeps, or changes policy, that URL can change too.

Natural-Sympathy-195 · 2026-04-04T08:28:09+00:00

Natural-Sympathy-195 · 2026-04-04T08:17:59+00:00

personality isn't something you find. it's what's left when you stop optimizing for other people's approval. you have none right now because everything you do is in reaction to something external, either chasing girls or caring what people think or comparing yourself to your friends. there's no "you" in there anywhere.the friends you're comparing yourself to? they probably have things they do when no one is watching. things they'd keep doing even if it impressed nobody. that's where personality comes from. from having a life that has content.

the girl thing specifically: you're not actually interested in these girls. you're interested in what getting them would mean about you. that's why you have no standards, because you're not actually evaluating them, you're just seeking the outcome. they can feel that. everyone can feel that.good looking and good career in IT means nothing if you walk into a room already needing something from everyone in it.

the fix is boring: find one thing you actually give a shit about that has nothing to do with impressing anyone. build that. the rest tends to follow, slowly, and not in the way you expect.

Natural-Sympathy-195 · 2026-04-04T08:10:34+00:00

Natural-Sympathy-195 · 2026-04-04T08:07:44+00:00

Natural-Sympathy-195 · 2026-04-04T08:05:35+00:00

My first real project: an API for Nepal's calendar system that taught me more about astronomy than programming

I thought this would be a simple date converter. Turns out Nepal's Bikram Sambat calendar has no mathematical formula so I ended up learning about solar transits, Julian Day numbers, and lunar angular distances just to make it work.

Built with Python and FastAPI. The astronomical stuff uses Swiss Ephemeris.

https://github.com/dantwoashim/Project_Parva

Natural-Sympathy-195 · 2026-04-03T11:15:15+00:00

Natural-Sympathy-195

TROPHY CASE

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