https://guptasanjay.com.np/blog Engineering write-ups by Sanjay Gupta on decisions behind FLITO, Duleko and other projects. en Mon, 19 Oct 2026 14:55:23 GMT https://guptasanjay.com.np/blog/duleko-who-can-call-me-phone-numbers https://guptasanjay.com.np/blog/duleko-who-can-call-me-phone-numbers Mon, 19 Oct 2026 00:00:00 GMT How Duleko keeps phone numbers private: their own table, one can_call() check behind every Call button, and a chat that refuses messages with a number in them. https://guptasanjay.com.np/blog/flito-road-distances-free-osrm https://guptasanjay.com.np/blog/flito-road-distances-free-osrm Mon, 19 Oct 2026 00:00:00 GMT How FLITO gets road distances and route lines from a free OSRM server: queued, batched, cached for a week, thinned to 5 m, and never fatal when it fails. https://guptasanjay.com.np/blog/duleko-verified-badge-id-checks https://guptasanjay.com.np/blog/duleko-verified-badge-id-checks Tue, 13 Oct 2026 00:00:00 GMT How Duleko made its verified badge mean an ID was checked: photos in a private bucket, 10-minute links, and a badge only one Postgres function can grant. https://guptasanjay.com.np/blog/duleko-map-without-revealing-where-people-live https://guptasanjay.com.np/blog/duleko-map-without-revealing-where-people-live Sun, 11 Oct 2026 00:00:00 GMT How Duleko's map shows skilled people nearby without revealing where anyone lives: a work area picked once, ~1 km squares and counts for guests, in Postgres. https://guptasanjay.com.np/blog/flito-invoices-fees-nepali-calendar https://guptasanjay.com.np/blog/flito-invoices-fees-nepali-calendar Tue, 06 Oct 2026 00:00:00 GMT How FLITO records payments it never holds, bills truck owners by Nepali month, and numbers PDF invoices per Nepali fiscal year, with dates in Bikram Sambat. https://guptasanjay.com.np/blog/duleko-android-notifications-without-firebase https://guptasanjay.com.np/blog/duleko-android-notifications-without-firebase Tue, 06 Oct 2026 00:00:00 GMT Duleko's Android app shows chats and work requests in the notification bar with no push service, and keeps email inside Brevo's free 300 a day. Here's how. https://guptasanjay.com.np/blog/epam-interview-experience-ai-native-intern https://guptasanjay.com.np/blog/epam-interview-experience-ai-native-intern Mon, 28 Sep 2026 00:00:00 GMT My EPAM campus placement experience (August 2026): eligibility, the LRU cache coding round, the GD topic, technical interview questions and tips that worked. https://guptasanjay.com.np/blog/study-engineering-in-india-from-nepal https://guptasanjay.com.np/blog/study-engineering-in-india-from-nepal Sun, 27 Sep 2026 00:00:00 GMT Why I chose to study engineering in India instead of Nepal: the IOE entrance, Chitkara fees and Nepali student concessions, placements, and the honest trade-offs. https://guptasanjay.com.np/blog/building-duleko-as-tech-lead https://guptasanjay.com.np/blog/building-duleko-as-tech-lead Fri, 25 Sep 2026 00:00:00 GMT As Tech Lead of Duleko, a bilingual local skills marketplace for Nepal, I own the platform end to end. Here's what's live today - guest browsing, typo-tolerant distance search, price negotiation, per-person call privacy and a native Android build - the one rule every screen is held to, and what we're building next. https://guptasanjay.com.np/blog/flito-freight-matching-which-truck-fits https://guptasanjay.com.np/blog/flito-freight-matching-which-truck-fits Fri, 25 Sep 2026 00:00:00 GMT FLITO filters out every truck that can't do a job, scores the rest out of 100 on fit, proximity, reputation, price and readiness, and reserves a truck's days with one conditional write so two bookings can never land on the same truck. Here's how the matching works and why. https://guptasanjay.com.np/blog/making-a-react-portfolio-crawlable https://guptasanjay.com.np/blog/making-a-react-portfolio-crawlable Thu, 24 Sep 2026 00:00:00 GMT This site is a Vite + React single-page app, which by default hands crawlers an almost empty page. Here's how one metadata table now drives both the live React head and a prerendered HTML file per route, why the sitemap dates come from git, and what Google's Rich Results Test still caught. https://guptasanjay.com.np/blog/postgres-row-level-security-business-rules https://guptasanjay.com.np/blog/postgres-row-level-security-business-rules Tue, 22 Sep 2026 00:00:00 GMT Duleko's work lifecycle - pending, accepted, confirmed, completed - is modelled as Postgres triggers with Row Level Security on every table, so a modified client can't skip a step. Here's why that decision, plus the outbox pattern behind its notifications. https://guptasanjay.com.np/blog/hash-email-verification-codes-like-passwords https://guptasanjay.com.np/blog/hash-email-verification-codes-like-passwords Tue, 22 Sep 2026 00:00:00 GMT A 6-digit email code is a password with worse UX expectations and a shorter lifespan - so FLITO stores only its hash, expires it in 15 minutes, burns it after one use, and locks out after 5 wrong tries. Here's the reasoning and what it protects against.