The R&B slow-burners and bouncy pop jams on 19-year-old Canadian singer Alessia Cara’s debut EP feel more like a personal manifesto than a party playlist. On her excellent single “Here,” she’s an “anti-social pessimist” brooding over a Portishead sample; on the joyous “Seventeen,” she provides a savvy update on Janis Ian’s “At Seventeen” and Fleetwood Mac’s “Landslide.” Later on, Four Pink Walls takes a turn toward retro soul, successfully channeling the conversational style of Cara’s hero Amy Winehouse. “Went from ‘when boredom strikes’ to ‘Ms. Star on the Rise,'” Cara sings. She’s unapologetically young, and only going up from here.