Her trajectory could have followed a different course. In her Into the Gloss days, she modeled in Derek Lam’s look book and kept up her signature platinum hair. Since then, she has mostly stopped going to fashion events and no longer has a dye job that requires laborious touch-ups. We talk about the parallel universe where Weiss is an influencer instead of a CEO. “I would be at the Valentino dinner right now with [Danish stylist] Pernille Teisbaek and all those girls, who I love.” She smiles a little dreamily, or maybe in relief.

There’s a vulnerability to Weiss’s transformation away from fashion darling to a woman in her mid-30s trying to figure out her life, like so many of us. Of course she doesn’t have it all. The third part of the Glossier slogan (“Smile Always”) is the hardest one to master, especially when you’ve made it to the top. Besides, is that mandate of perpetual cheer setting the bar too gratingly high? The brand’s sheen of optimism can occasionally give off a saccharine aftertaste. But, in the right light, “Smile Always” isn’t a denial of real-life complexity (girls who tag Glossier in their moody selfies prove as much) but an upbeat allowance to fake it till you make it. It’s the wellness era’s version of dressing for the job you want. Weiss is doing her own dabbling on the self-care front. She disappears into her bedroom to fetch a gratitude journal she writes in for five minutes each day. I imagine super intern Emily would have stifled a laugh if the words gratitude journal had ever come up.

But Weiss knows where her young audience is going. She has personally invested in the Co-Star astrology app—an addictive thrill in this second age of Aquarius. She is also nurturing the next generation of Emilys, investing in Supersystem, a political-platform start-up from her former assistant, Morgan Von Steen. It seems inevitable that a Glossier book—part self-help, part success tale—could be on the way. Weiss has plowed through the genre over the years (they helped, she says, but no book can tell you how to be a CEO), and I scan the shelves of her color-coded library. (In the white section: Small Fry, Sensemaking, Grit, and The Innovator’s Dilemma: When New Technologies Cause Great Firms to Fail.) Meanwhile, she has recently whittled down the accounts she follows on Instagram to a lean 555. One that made the cut is Blue Zones, which rounds up “happiness secrets from the most extraordinary populations on earth.” Like all good tech CEOs, Weiss is interested in longevity.

The Glossier flagship on a Saturday afternoon is a real scene. Since the permanent location in SoHo opened last November, some 50,000 visitors pour through its doors each month. Today, in high summer, the line to get in is running halfway down the block. Editors, as the store employees are called (customer-service reps are online editors), mill about on the sidewalk, dressed in light pink jumpsuits with stickers that declare their preferred pronouns. They are offering hits of Invisible Shield SPF 35 and Soothing Face Mist to help ease the wait. Weiss hugs editor after editor as we make our way inside, where a wholesome scene is playing out: tweens teaching each other how to apply mascara, a mother-daughter pair comparing swatches of eyeliner on their wrists.

The interior was designed to incite maximum Instagram engagement, with eight-foot-tall tubes of Boy Brow and an undulating banquette in the shape of red lips. At the opening party, Weiss, wearing a tuxedo with no shirt underneath, led Serena Williams and her husband, the Reddit cofounder Alexis Ohanian, on a tour of the space. The next morning, Williams posted a snapshot of the night with the caption “Bossed up with @emilyweiss.” (Ohanian, meanwhile, was a prime candidate for @glossierboyfriends, among the several meme accounts on Instagram. This one—showing supportive, often bored partners at the stores—is run by 29-year-old Dani Barrett. “I get a lot of DMs asking, ‘How do I find a Glossier boyfriend?’ ” she says. Her response: “You don’t just find them. You have to work to shape them.”)