Optimus Transfer

The task

Client invoices arrive as PDFs and somebody has to retype them into the accounting software. The work is monotonous, and a typo in an amount or a tax number is expensive and hard to spot — nothing breaks, the books are simply wrong. Off-the-shelf tools either charge per document or require other people's data to sit on somebody else's server, and a practice this size can accept neither.

Approach

1. 01

   The invoices are text PDFs with a consistent layout, so the data is extracted by rules over text coordinates rather than by shipping the document to an external service. As a result the application never touches the internet, and the cost per invoice is zero.

2. 02

   Amounts in the XML are computed from the line items and tax rates, never copied off the paper. The program then checks that total against the one printed on the invoice; if they disagree, no XML is produced and the interface says why. That check is the only thing standing between a misread invoice and a wrong set of books.

3. 03

   Every invoice in the list carries a plain status — ready, check this, needs input, totals do not match — so the accountant opens the exceptions instead of reviewing every document.

4. 04

   The program remembers customer tax numbers, so next month they fill themselves in for the same customer. Invoices made out to buildings and owner associations carry no customer tax number at all, and the program treats that as normal rather than as an error.

5. 05

   A single general profile handles fiscal receipts from any software and at any tax rate, including several rates on one invoice. A VAT-exempt invoice under article 90(2) is a special case of the same model, not a separate branch of code.