He is known for The Epic Tales of Captain Underpants, Kung Fu Panda: Legends of Awesomeness, Animaniacs, Teenage Mutant Ninja Turtles and Pinky and the Brain.

[2] Hastings had originally intended to be a musician, but after graduating from Berklee College of Music in 1984, he joined the L.A. improv comedy troupe The Groundlings.

Hastings also wrote two 1995 spin-off TV movies "A Pinky & the Brain Christmas Special" and "Tiny Toons' Night Ghoulery."

In 2010, Hastings began developing the cartoon series Kung Fu Panda: Legends of Awesomeness, based on the film, for Nickelodeon.

DreamWorks Animation announced a film adaptation of Dog Man in December 2020,[4][5] with Hastings directing after his experience with Pilkey's works from The Epic Tales of Captain Underpants (2018–20).