About

Welcome to my portfolio! My name is Tereza Marková, but in the creative world, I craft under the name Undie. While my professional journey began in the structured world of corporate finance, I always felt a yearning for something more tangible—something that allowed me to work with my hands and bring ideas to life in the real world. So, in 2023, I took the leap to reconnect with my passion for craftsmanship, and that's how Undie was born.
It all started with a single design: the Biggie Bag. From the beginning, my focus has been on creating unisex designs that resonate with an outdoor spirit—because that’s a reflection of who I am. I love versatility and multifunctionality, and I strive to weave those values into every piece I create. My designs aren’t just accessories; they’re tools meant to adapt to your lifestyle and stand the test of time.
I primarily work with durable, high-quality outdoor materials sourced from local suppliers, but sustainability is a cornerstone of what I do. That’s why I also incorporate secondhand and deadstock fabrics wherever possible, giving new life to materials that might otherwise go unused. Every bag is thoughtfully designed and lovingly handcrafted by me, with an emphasis on quality and individuality. While my core designs are customizable to suit your needs, I’m always excited to collaborate on fully custom creations from scratch—those projects ignite my creativity the most.
At Undie, I believe in a philosophy of repair and sustainability. Instead of replacing your belongings when they wear out, why not fix them? If your Undie bag ever needs a little bit of love, just let me know, and I’ll be happy to repair it for you. It’s my small way of encouraging a world that values durability, mindfulness, and conscious consumption.
Thank you for stopping by—let’s create something meaningful together!

Biggie

Biggie - Also known as the design my friends wouldn’t let me keep to myself, this bag holds a special place in my journey—it’s where it all began. The inspiration struck during a frustratingly familiar moment: a quick trip to the grocery store, only to realize I’d forgotten my trusty tote bag. With nothing to carry my groceries in, the idea for a smarter, more versatile bag was born. I wanted something that wasn’t just functional but seamlessly fit into everyday life—perfect for city strolls with a spontaneous stop at the market.
And so, the Expansible Bag came to life. Designed to adapt to your needs, this bag expands both horizontally and vertically, offering flexibility for whatever your day holds. Whether you’re carrying a few essentials or loading up with fresh produce, it adjusts effortlessly. The secure zip closure keeps everything safe, while a handy interior pocket provides the perfect spot for your smaller must-haves—keys, wallet, or phone. The adjustable straps ensure a comfortable fit, tailored just for you, no matter your height or how you prefer to wear it.
It’s more than just a bag—it’s a problem solver, a daily companion, and a reflection of my love for thoughtful, functional design.

Ocean

With this design, I wanted to bring my favorite creative technique to life—a unique, stretchy thread style I call freestyle. It’s an organic process that adds texture and personality to every piece, making each bag one-of-a-kind. No two are exactly the same, and that’s what I love most about it—the individuality stitched into every thread.
Versatility is at the heart of this bag. Thanks to its adjustable straps, you can wear it in whatever way suits your vibe or needs: as a fun and functional fanny pack, a stylish crossbody, or effortlessly slung over your shoulder. The original design features a sleek magnetic closure for easy access, but if you prefer something more secure, I can swap it out for a zipper—customization is always an option.
What’s more, the size is completely up to you! Whether you need something compact for your essentials or a roomier version to fit your on-the-go lifestyle, we can tailor it to fit your world. It’s a bag that’s as flexible and unique as you are, blending style, function, and just the right touch of individuality.

Reverse

Dreaming of packing light for your vacation but worried about finding a bag that matches all your outfits? Or you just can not decide which color of bag you need? Let me introduce The Reverse Bag—your ultimate style chameleon. With this clever design, you’re essentially getting two bags in one. Whether you want to match your look, suit your mood, or switch things up mid-day, this bag makes it effortless. Simply flip the body of the bag, and voilà—a whole new vibe.
The adjustable strap ensures a perfect fit, so you can wear it comfortably all day long, no matter where your adventures take you. Plus, the colors, fabrics, and details are fully customizable, allowing you to create a bag that reflects your personal style. The magnetic closure is a thoughtful touch, designed specifically to maintain the bag’s reversibility while keeping your belongings secure.
It’s more than a bag—it’s a versatile, stylish problem-solver that’s ready to adapt to your life, your wardrobe, and your travels.