Granat antique house

The shop on Birzhan Sal has been open for more than ten years: porcelain and crystal, figurines, clocks, imperial and Soviet coins, banknotes, gold and silver. It has 7,500 followers on Instagram, but sales happened in private messages. Buyers from other cities asked for photos of every item in WhatsApp, and prices were negotiated one by one.

We moved the showcase onto the website and added the shop's own auctions. The owner lists a lot and sets the bid step and a reserve price, and buyers bid online from any city. Everyone sees the price change without reloading the page, and a bid in the last minutes extends the auction, so nobody wins with a bid one second before the end.

The first auction got 23 bids from 9 people, and the lot sold for 3.4 times its starting price. Every item in the catalog is one of a kind, so sold items don't disappear: they stay in the catalog marked "sold", which works as the shop's portfolio.

How it's built

The site runs on its own Rust server with a PostgreSQL database. Every bid is one transaction that locks the lot, so two bids in the same second can't both win: we test that with 60 simultaneous bids.

Every bidder sees the price change without reloading. Updates ship with one command, and if a new version doesn't respond, the server puts the previous one back by itself.

Who this suits

Antique and jewellery shops, galleries, collectors, and anyone selling one-of-a-kind items who wants the best price through bidding rather than long back-and-forth messages.

What's inside

• Catalog with 6 sections and filters by price and category
• Auctions with automatic bidding up to a set maximum and a hidden reserve price
• Anti-sniping: a bid in the last 3 minutes extends the auction by 2 minutes
• Bidders sign in with an SMS code, no passwords
• If the winner doesn't pay, the lot is offered to the next bidder
• Owner's panel: add an item and start an auction from a phone
• A separate phone line and WhatsApp for the antiques department
• Russian and Kazakh

Rust (axum), PostgreSQL, real-time price updates (SSE). Server updates take one command and roll back automatically if anything goes wrong.