Hello! My name is Kat, and
I’m a Product Designer.

Hello! My name is Kat, and I’m a Product Designer.

Hello! My name is Kat,
and I’m a
Product Designer.

Currently crafting innovative retail experiences @ shopreme

Currently crafting innovative
retail experiences @ shopreme

design systems

interfaces

strategy

usability

design systems

interfaces

strategy

usability

Recent projects

shopreme

Creating one-stop self checkout solutions that help bridge the gap between physical and digital shopping experience.

shopreme is a company providing software and hardware solutions for the retail sector - from traditional self-checkout machines, exit solution, mobile scan & go app and more. All to help shoppers and stores coexist more efficiently.

I've worked on designing all parts of the product, ensuring consistency and ease of use for our B2B customers and a good shopping experience for end users.

Deliverables

Product design, visual design, UX strategy, UX research

Visit Site

Product promo Video

packup

Get out the door faster and safer with packup’s trip generator and inventory management tools.

packUp is a web and mobile platform for backpackers and travelers to manage their gear inventory and plan trips. I've been approached by their team to conduct the audit of their product to find and improve user conversion. We've tested the product to find the pain points in their onboarding and general user flow. The plan was not to only redesign, but build and improve on the already existing product

In the end the product got a small branding refresh, improved features and UX, and a design system to let the team easily create and maintain the future screens.

Set to re-release Q2 of 2025 :)

Deliverables

UX audit, UX research, branding, product design

About

Heya, my name is Katja Sostar.
I'm a product designer with 5 years
of experience.

Heya, my name is Katja Sostar.
I'm a product designer with 5 years of experience.

All about mixing design with empathy, and transforming challenges into solutions to make people’s lives easier and this world better.

Currently based in Graz, Austria. Working @ shopreme, where I'm helping bridge the gap between physical and digital shopping experience, and building products that are used by 50+ million people.

Originally studied computer science and worked as a front-end developer before finding my passion in solving gnarly UX problems as well as designing delightful interfaces.

Over the years I've worked in agencies and in-house, where I've been a part of developing multiple products from scratch, as well as refining existing solutions.

I've participated in and lead design sprints and workshops to help companies define their business goals, conducted user testing to understand users needs and behaviours, and built design systems to help teams streamline their development processes.

When I'm not designing you can find me outside cycling, running, or on bad weather days inside playing video games and reorganising my spotify playlists.

Skills & Toolkit

Skills & Toolkit

Skills & Toolkit

Interaction design

Interaction design

Interaction design

Creating interfaces, focusing on content structure, intuitive UI patterns and simple interactions

Figma

Adobe CC

Framer

Rive

User experience & research

User experience & research

User experience & research

Conducting research, interviews and testing to understand user behaviours and needs

Figjam

Miro

Maze

Userbrain

Design systems

Design systems

Design systems

Setting up and maintaining scalable and reusable designs systems.

Figma

Zeroheight

Playbook

Product strategy

Identifying product goals and ensuring that designs fit into business objectives

Notion

Jira