FreeSewing is the leading open-source library for parametric sewing patterns and combines sewing patterns with code; instead of drafting patterns on paper (hardly an easy task!), you can now enter the measurements of your body into the platform to get a sewing pattern that fits YOU. In this talk, I will introduce you to FreeSewing, the sewing world as a whole and FreeSewing's role in it, and I will show a peek under the hood of a FreeSewing pattern.