PayNex: a cloud POS and fiscalization platform for web, mobile and POS terminals

Fiscal compliance and point-of-sale software are often complicated: staff need training, settings require a developer, and every regulation change means another update.

PayNex set out to make that simple. Business owners should be able to run sales, payments and compliance themselves, on whatever device they have, and keep selling even if the internet connection drops.

We designed a cloud-first architecture that supports real-time fiscalization, works across devices and receives compliance updates automatically. The Next.js web application handles configuration, reporting and remote access, backed by Node.js and Express APIs and a PostgreSQL database.

For the point of sale, we built Flutter apps for iOS and Android from one codebase, optimized for speed and offline handling. A self-service settings area lets businesses change items, prices, payment methods, user roles, tips and workflows without writing code. Security, uptime and scalability were core priorities throughout.