[vineel567]

How are those awesome illustrations created. Which tool????

[barbecue_sauce]

Looks a bit like balsamiq. But there's also this tool called "on-staff graphic designer/illustrator" that they could have used as well.

[kaycebasques]

Mariko made all of those illustrations herself. Check out her “alternative introduction to promises” [1] on her personal blog.

[1] https://kosamari.com/notes/the-promise-of-a-burger-party

[barbecue_sauce]

Self-production also always an option.