Writing a JavaScript Fee Engine to Protect My Etsy Margins

I still remember the exact moment I made my first sale on Etsy. It was a handmade leather wallet, and I was thrilled. But a few days later, when the deposit hit my bank account, my excitement turned into confusion.

Source: [Dev.to](https://dev.to/sellermind/writing-a-javascript-fee-engine-to-protect-my-etsy-margins-53p)