Engineering case
A seller on a platform with no API
The bot runs a seller storefront: answers buyers, delivers goods, watches neighbouring prices. The platform has no machine interface, so everything goes through the same channel a visitor uses.
The platform defends itself against automation, and that shaped the client: it signs on the wire exactly as a real browser does, an external service solves the «I am not a robot» challenge, and some requests leave through a relay of our own because the platform keeps an address allowlist.
A seller session is short-lived and dies silently, so refresh runs on a schedule with retries on disconnect rather than on error: by the time an error appears the order is already lost.
Python · Telegram Bot API · Docker