Self-taught sewist here. I built an app so I could see a garment before cutting into expensive fabric

I taught myself to sew with persistence and a healthy jealousy fueled from watching TikTok videos. I mostly sew for my daughter, usually from vintage patterns, and my biggest problem was never the sewing. It was that I couldn't picture the finished thing, especially once I started changing the pattern. If I want to lower the neckline, lengthen the bodice, take the sleeve from a different pattern… I had no idea what I was about to make. I wasn't going to cut $30-a-yard fabric f