Built a Nepali calendar computation engine in Python, turns out there's no formula for it
What My Project Does
Project Parva is a REST API that computes Bikram Sambat (Nepal's official calendar) dates, festival schedules, panchanga (lunar almanac), muhurta (auspicious time windows), and Vedic birth charts. It derives everything from real planetary positions using pyswisseph rather than serving hardcoded lookup tables. Takes actual lat/lon coordinates so calculations are accurate for any location, not just Kathmandu.
Target Audience
Developers building apps that need Nepali calendar data programmatically. Could be production use for something like a scheduling app, a diaspora-focused product, or an AI agent that needs grounded Nepali date data. The API is public beta so the contract is stable but not yet v1. There's also a Python SDK if you want to skip the HTTP boilerplate.
Comparison
Most existing options are either NPM packages with hardcoded month-length arrays that break outside a fixed year range (usually 2000-2090 BS), or static JSON files someone manually typed from government PDFs. Both approaches fail for future dates and neither accounts for geographic location in sunrise-dependent calculations. Hamro Patro is the dominant consumer app but has no public API, so developers end up writing scrapers that break constantly. Parva computes everything from Swiss Ephemeris, which means it works for any year and any coordinates.