I love this story. I can intensely relate as I too have made the pivot from being a UX professional to software engineering a few years back. Sure I hadn't achieved anything close to being the director of design for a known tech firm; My design career was just starting to flourish when I'd made the move. But so much of the sentiment regarding confidence and self-doubt were the exact emotions that I had experienced . It felt as if there was this huge gap in knowledge that I'd never be able to fill. It took a lot of effort from me to overcome that fear of inadequacy and make the jump, so I know it must've not been easy for the author either. It's also funny how the activities she chose to express her desire to code - tinkering with Arduino, participating in Ludum Dare - were the exact stuff I was doing too!
Huge congrats to Kristina, and I hope her engineering career brings her as much joy and fulfillment as it has brought me.