A quick search for an ATtiny85 programmer will yield a variety of ATtiny85 programmers. Some slick, some that don’t work, and a variety of other possibilities. After downloading some Eagle board files for one of them and after ordering and soldering the necessary components myself, they didn’t work. It was either my soldering, the PCB manufacturer, or the boards themselves were defective. I was about to order another design I found until I realized I had all I needed on hand.