It’s hard to rattle Tristan Walker. Maybe that’s because he grew up one of three kids, kept on the straight-and-narrow by a hardworking single mother in the projects of Queens.

Or maybe that’s because he constantly worked his ass off to build a better life for himself, always beating the odds, whether it was his scholarship to attend the elite Hotchkiss boarding school, attending Stanford’s Graduate School of Business, getting an early internship at Twitter, and then jumping to Foursquare to lead business development when it was scorching hot, before then grabbing an entrepreneur-in-residence slot at top venture capital firm Andreessen Horowitz. And that level of success frequently meant being the lone African American man in the ro...