Telegram bot and Mini App

Pereplyot: a bookshop inside Telegram

A bookshop inside Telegram: Russian classics, bought with play money and read right in the messenger.

The task

Sell digital goods where buyers already spend their time, with no separate website and no app from the store.

What we built

MTProto bot: catalogue, library and balance in the chat
Mini App with search, a wallet and a reader
The balance never goes negative, a book cannot be bought twice
The server checks the signature of the data from Telegram

A shop with no website and no app

Pereplyot sells books where the buyer already spends the day. Nothing to download: the shop opens from a button in the chat. The bot shows the catalogue and the library, and the Mini App adds search, a wallet and a reader.

The demo uses play money so anyone can go through a whole purchase. A real shop puts a payment provider in its place, and the mechanics stay the same.

What keeps a purchase from breaking

The balance never goes negative, even after two quick taps on “buy”.
A book cannot be bought twice: the server checks it instead of trusting the button.
Every request from the Mini App is signed by Telegram, and the server checks the signature. Nobody can buy on someone else’s behalf.

Who this suits

The same mechanics serve a shop inside Telegram, a cafe with delivery and a booking bot: a catalogue, a choice, a confirmation, a payment and a personal account. If you are choosing between a website and a bot, read “A website or a Telegram Mini App”.