No offense to Jingle Ball but there is no better measuring stick for success than a Saturday Night Live musical guest spot. A night after performing to tens of thousands at Z100’s annual pop radio celebration at Madison Square Garden, Charli XCX had an appointment in front of millions thanks to SNL, who named the 22-year-old British hitmaker as their musical guest days before she releases her breakthrough album Sucker.

SNL marked the culmination of a huge year for Charli, with the singer performing two tracks off Sucker, one of Rolling Stone‘s Best 50 Albums of 2014. First up, her smash hit “Boom Clap,” a single that’s been around for over six months now, but Charli updated the track with a new wave gleam. “Boom Clap” has always been a lighters-in-the-air moment, but the SNL performance made it worthy of a prom in a John Hughes movie.

“Charli XCX is the pop star 2014 was waiting for: a badass songwriting savant who’s the most fun girl in any room she steps into,” Rolling Stone writes in their Best 50 Albums blurb for Sucker. “It’s a dance party, a mosh pit and a feminist rally – Charli’s definitely in charge.” That sort of dexterity was on full display when Charli performed her second song of the night, the punk anthem “Break the Rules.”

If her SNL “Boom Clap” was a nod to the Eighties, then “Break the Rules” was her ode to the Nineties, and Charli dressed the part. (The song’s music video also pays homage to Nineties dark comedies like The Craft and Jawbreaker.) This “Break The Rules” wasn’t as dynamic as the lollipop-smashing teenage riot rendition that Charli brought to the American Music Awards – the Christmas-lighted SNL stage disrupts the mood – but both performances were enough to let people know that Charli XCX is a force to be reckoned with in 2015.