First ever paid lines of code: in pascal, for pharmacy. Albeit, i did stock ordering portion. Stock only had 300baud demodulator so all verifications had to done by eavesdropping the line with phone and if one didn't hear the correct signal, you had to press keyboard to retrigger the batch again. I had to code all this blind too because there was no test environment :)
Nice! You are one better than me though, because I didn't have any connectivity with another system - it was all running standalone on their LAN. The stock room had to key in goods receipts manually after downloading info from their Vax PDP-8 stock management system. If I had more time (and they had more money) I might have worked out a way to automate that. :)