LOS ANGELES—Working at a clip only slightly faster than usual, a team of professional songwriters spent a half hour banging out a new song that will define local teenager Destiny Cibula’s personality for the next two years, sources reported Thursday. “All right, let’s wrap this one up and get to lunch,” a 47-year-old Swedish producer said of the future chart-topper that features a chorus written in 20 seconds and that will prove formative to Cibula’s adolescence, changing the way she sees herself and, years later, encapsulating more than anything else the nostalgia she feels for her youth. “Keep it simple—hit the root, the fourth, the fifth. There we go. ‘You’re a bird, spread your wings, blah blah blah.’ Just copy and paste the beat from whatever worked last time, as long as it’s something you can dance to at a wedding. And hurry up, I have a one o’clock reservation.” At press time, the songwriters had reportedly returned from lunch and were already putting the finishing touches on another song, this one a down-tempo number that a ninth-grade Cibula will play on repeat for hours after going through her first breakup.