Macer is a 1993 graduate of Vassar College. She began her career in theater arts in New York City.
She co-produced an independent feature film, Park Day and won the Audience Award at the Urban World Film Festival for that movie.
She then focused on television. She worked as an assistant at Nickelodeon Movies and a creative executive for the Walt Disney Company. She was then selected by the Fox Writers Program. She was a producers' assistant for the second and third seasons of 24. She went on to become a writers' assistant for the first season of Lost in 2004. Macer and the Lost writing staff won the Writers Guild of America (WGA) Award for Best Dramatic Series at the February 2006 ceremony for their work on the first and second seasons. She became a story editor and writer on Prison Break. She was an executive story editor for the short-lived Knight Rider remake.
Prison Break episodes
- 1.08 - "The Old Head" (written)
- 2.06 - "Subdivision" (written)
- 2.11 - "Bolshoi Booze" (co-written with Seth Hoffman)