I have a very big experience in working with self service systems: https://www.dropbox.com/s/x6r6mnn6i2edmkl/self-kiosk.pdf?dl=0 I am the developer of the server software under Unix and embedded systems. I fully developed the system of payments for the company , the software for the payment terminal, the server processing and gateway to the outside of the company. Excellent knowledge of C++ (STL, Boost), libuv (async networking), C, Assembler. Excellent understanding of the principles of operation of network. I have experience in development of network software (client, server). Worked with hardware: POS printer, billacceptor, barcode scanner. Developed the system of drawing for GUI over Linux framebuffer. Before I started to work on this project I used to work in a bank in the Electronic Payment department as a developer of software and technologies. Please contact me so we can discuss your needs. Then i can show you the most relevant examples of my work and also provide you with references.