4 description: Learn about some of the best practices we've gathered from years of working on and using Bootstrap.
8 We've designed and developed Bootstrap to work in a number of environments. Here are some of the best practices we've gathered from years of working on and using it ourselves.
11 **Heads up!** This copy is a work in progress.
16 - Working with Sass files
17 - Building new CSS components
18 - Working with flexbox
19 - Ask in [Slack](https://bootstrap-slack.herokuapp.com/)