How to Build a Node.js Service That Prints POS Receipts via a REST API

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A developer tutorial on DEV Community walks through building a small Node.js service that sends point-of-sale orders to a thermal receipt printer. The setup uses Node 18 or newer, TypeScript, and Express, with no need to install any software directly on the printer. Orders are formatted as HTML and submitted via a POST request to the Receiptful API, which handles the conversion to ESC/POS printer commands. Credentials such as the API key and printer ID are stored as environment variables to keep them out of source code. The guide covers order data modeling, receipt HTML rendering, and wiring the print function to an Express route endpoint.

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ProgrammingDEV Community ·

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