Hugo Giraudel shares his journey of building SassyLists. SassyLists is a toolbox providing almost 40 functions to help working with Sass lists. The Sass default list API is very light therefore you might need some extra functions, especially if you are building a Sass framework or a robust grid system.
Mixins are one of the most powerful features of Sass. Mixins allow for efficient and clean code repetitions as well as an easy way to adjust your code with ease. If you are using Sass in your development workflow, no doubt you are using some of the mixins that I have covered below but some might also be new and helpful.