Invoicing automation for an e-shop

The problem

Invoices were created and reconciled by hand from e-shop orders — slow, error-prone, and risky when numbers have to be exact and match the accounting system. They needed invoicing to happen automatically, correctly, and feed straight into their Czech accounting software.

What we built

A financial application that creates and tracks invoices automatically. When an order in their e-shop is fulfilled and paid, the e-shop calls our app over an API; the app generates the invoice from the order's data and hands it back, so the customer gets it without anyone lifting a finger.

Everything is stored, calculated and exportable. Money math uses exact decimal arithmetic — not floating-point, which silently rounds wrong — and the finished data exports as clean XML straight into a Czech accounting program. Where documents are parsed by OCR, an LLM re-checks the extracted data before it's trusted, so a misread doesn't become a wrong figure.

• Automatic invoice generation triggered by the e-shop over an API
• Exact, decimal-precise calculations — no floating-point rounding errors
• OCR document parsing with an LLM re-checking the extracted data
• Full storage, tracking and recalculation of invoices
• XML export straight into Czech accounting software
• Two-way flow: order in → invoice back to the e-shop → customer

Technical implementation

Status

Live for the client. Because the project is under NDA — the company, the domain and the application's internals — there are no screenshots and no real data here; this is a high-level description only.