IF ONE WISHES TO DEVELOP A POINT OF SALE APPLICATION WITH NIM, WHAT TOOL TO USE AND THAT ALSO ALLOWS GENERATING PDF REPORTS, AND HANDLING TICKET PRINTERS?
NimPDF, or if you're using Gtk you can pull it WebKit and then generate the report as HTML and print that as a PDF.
For ticket printers you likely either have a DLL/so/dylib file or just a serial connection. So either wrap the interface from the dynamic library, or just interact with the serial port.
Dunno about UI, but Ninja is incredibly good for templating HTML printable pages (CSS has rules for that). Then you feed it either to Gotenberg (https://gotenberg.dev/), or I believe Chromium on CLI has a flag to pass in HTML pages and output PDF.