There is nothing more satisfying than refactoring code to something nice and condensed, but still very readable. A lot of my personal favorite experiences come

There is nothing more satisfying than refactoring code to something nice and condensed, but still very readable. A lot of my personal favorite experiences come from working with trees, since recursive code can be so lean and beautiful. I write a 5ish line function to generate a graphviz file to render by AST once and I still look back on that as beautiful code.