How I built a Python Flask POS system with a mechanical discount lock slider 🔐

Hey everyone!

I wanted to share a micro-SaaS architecture I've been working on to solve a real retail problem: cashiers burning store profit margins by giving unauthorized discounts.

I built Reativa Zap Pro, a lightweight web POS register using Python Flask and SQLite.

The Solution: Mechanical Slider Lock

Instead of a complex backend permission system, the core feature is a dynamic UI discount slider that mechanically locks and limits input based on customized price ranges defined by the shop manager.

Technical Stack:

• Backend: Python 3.x / Flask Framework
• Database: SQLite (zero configuration, standalone .db)
• Frontend: Premium Dark Mode UI with high-contrast Neon Green elements.

I have packaged the entire source code clean, modular, and with an automated .bat initializer script so anyone can deploy it instantly or use it as a robust boilerplate to build their own software business.

If you want to check out the clean code structure or grab a commercial license for your own projects, the deployment is live on Gumroad:

👉 Get the Full Source Code on Gumroad

Let me know what you think about this UI approach!