Hey Product Hunt! I'm a designer, full-stack developer, and entrepreneur who loves making and launching all sorts of products. Over the past few years I've built a real-time collaborative map tool, one of the most popular flowcharting libraries

I think the question is a very straightforward but a tricky one! You are given the ability learn and master ANY skill in the span of day. The logistics don't matter, it will be done. Which skill do you choose?