He is from Brazil and speaks portuguese.
Discussion
I don't know know him personally and I didn't actually listen to the interview yet but I always thought he was American because his GitHub says he is in Massachusetts, USA.
I've never heard or met any Brazilians so I wouldn't recognize a accent from there.
I may have come across as rude, but that wasn't my intention, I just wanted to clarify why he has an accent 🤝
I don't know English fluently 😅