Microscopes to Materials: A Radical New Chapter in Ethical Fashion with Rachel Lee, Hydefy
From NASA to the Runway: How Hydefy is Turning Fungus into Fashion’s Next Frontier
Rachel Lee didn’t set out to reinvent the materials industry. But when a NASA-backed fungi sample from Yellowstone met her passion for global development and biotech, a new era of sustainable fashion was born. As the founding partner and general manager of Hydefy, Rachel is leading a team that's transforming extremophile fungi into a sleek, high-performance alternative to leather, one that’s already graced the runway thanks to a collaboration with Stella McCartney.
On this episode of The Wild Party Podcast, Rachel joined Stefanie LaHart to talk about Hydefy’s origin story, the science behind their groundbreaking material, and why fungi may just be the future of fashion.
A Mission-Driven Pivot from Global Philanthropy to Material Innovation
Before co-founding Hydefy, Rachel worked in global development, philanthropy, and biotech, driven by a singular question: How can we allocate the world’s natural resources more sustainably?
“I’ve always been really motivated by solving a problem I’m passionate about or building toward a North Star,” Rachel explained. “Originally, that started with hunger and food systems, which led me into biotech. But eventually I became passionate about entrepreneurship because we need scalable solutions.”
That passion led her to Nature’s Fynd, a biotech company using fungi to create vegan proteins. It was there that the idea for Hydefy was born: if this extremophile fungus could be used for food, what about fashion?
A NASA Discovery, a Yellowstone Fungus, and a Whole New Material
Hydefy’s hero ingredient is a rare fungi strain discovered in the volcanic geysers of Yellowstone National Park. Supported by NASA research into sustaining life in extreme environments, this extremophile organism thrives in hot, acidic conditions—and happens to produce a filamentous structure that mimics muscle tissue when fermented.
“When you looked at it under a microscope, it looked like muscle or protein,” Rachel shared. “And it had all the essential amino acids. Someone even tasted it. That’s how the discovery started.”
From this base, Hydefy developed a fermentation process that combines the fungi with sugarcane-derived inputs to create durable, customizable material sheets. The result? A luxury-grade, animal-free, petroleum-free leather alternative that’s grown, not harvested.
Collaboration, Customization, and the Stella McCartney Effect
Hydefy’s big reveal came in partnership with Stella McCartney: a silver handbag made from Hydefy’s fungi-based material debuted in the designer’s runway collection.
“It was a pretty special collaboration,” Rachel said. “Their values and our values lined up, and they were really interested in the storytelling piece.”
The material itself isn’t a one-size-fits-all product. Hydefy can tailor the thickness, texture, finish, and even scent of the final sheets. While still a small team, they’re moving toward a production model that balances creative collaboration with scalable offerings.
“We’re not a traditional supplier,” Rachel said. “So the relationship with each brand also needs to evolve.”
Science Meets Storytelling in the Sustainability Conversation
Creating a new material from scratch hasn’t been without its challenges. Early versions of the product were hydrophilic, absorbing too much water. Making it more durable and water-resistant introduced new problems, like how it interacted with traditional manufacturing equipment.
But Rachel and her team embraced the complexity. “Our innovation isn’t just in the formulation, it’s also in how we process the materials,” she said. “We wanted to use common equipment and retrofit it for our needs, rather than building entirely new systems.”
That systems thinking extends to Hydefy’s sustainability ethos. The company prioritizes durable design, post-industrial recyclability, and minimizing harm throughout the supply chain.
“We’re made in America now, but our production model can be adapted anywhere,” Rachel noted. “That means we can shorten the supply chain and reduce emissions as we scale.”
The Future is Fungus and It's Closer Than You Think
What excites Rachel most? The tangibility of impact.
“When I see our work on the Stella McCartney website or in the hands of consumers, it’s real,” she said. “We’re not just talking about change, we’re creating something physical, something better.”
With applications that range from fashion to footwear to automotive interiors, Hydefy is attracting interest from brands that want to do more than just hit emissions targets—they want to tell a story about innovation and ethics.
“We want to give people more options. And in the next 20 years, this won’t be ‘new material’ anymore. It’ll just be material.”
🌐 Visit Hydefy online at hydefy.com
