Yay! David Spivak and Brendan Fong are teaching a course on applied category theory based on their book, and the lectures are on YouTube!
Their book is free here:
* Brendan Fong and David Spivak, _[Seven Sketches in Compositionality: An Invitation to Applied Category Theory](http://math.mit.edu/~dspivak/teaching/sp18/7Sketches.pdf)_.
If you're in Boston you can actually go to the course. It's at MIT January 14 - Feb 1, Monday-Friday, 14:00-15:00 in room 4-237.
They taught it last year too, and last year's YouTube videos are on the [same YouTube channel](https://www.youtube.com/user/youdsp).