This one started from a very ordinary campus problem: every semester, thousands of IIT Kharagpur students either haul stuff home they'll never use again, or buy new when a senior literally has the same thing sitting unused two hostels away. There was no trusted way to buy and sell second-hand on campus, just scattered WhatsApp groups where you can't verify who you're actually dealing with.

I built ThriftKGP to fix that, a campus-only marketplace where every listing is tied to a verified institute identity, so you're never buying from a stranger off the internet, you're buying from another IITKGP student.

Beyond the basic buy/sell flow, I built out four core modules that make it actually usable at scale: request boards (post what you're looking for instead of only browsing what's listed), wishlists, a review system so reputation carries across transactions, and an admin dashboard for oversight. I also automated listing moderation and buyer-request matching with event-driven background jobs, which cut down manual moderation work substantially, important once you're serving 16,000+ potential users and can't manually vet every post.

Stack: React, Node.js, Express, MongoDB, Tailwind CSS

It's since been recognized with a SELF RISE Innovation & Prototype Grant as a campus-wide second-hand marketplace concept.

If you're building a marketplace, community platform, or anything that needs trust and verification baked into peer-to-peer transactions, that's squarely in my wheelhouse.