MVP Hackathon

QR Carrot


Project lead & Design in team of

1 UX & 1 UI


2.5 days


Figma, Miro, Notion

abstract project cover


Marco manages two coffee shops in Berlin. As a small business owner, he doesn’t have a marketing budget to acquire new customers. Therefore, he relies on returning customers to keep his business healthy. Currently, Marco manages his community on social media, where he likes to reward customers that posts about his coffee shop, by offering them a free drink on their next visit. However, the process is messy for Marco and is employees, and not trustworthy for the customers.

The coffee shops in Berlin Prenzlauer Berg and Pankow. Pictures from @KiezKaffeeKraft


Before starting the hackathon, Marco shared with me his idea to digitalize the process of issuing rewards through QR codes, in order to increase the convenience and efficiency. The technical requirement were tested prior with a developer.


How to issue single use QR codes that allow customers to easily redeem a free drink on their next visit, without affecting the businesses’ current workflow?


Our goal as a team for the hackathon was to launch an MVP that has limited functionalities, in order to test Marco’s idea with early adopters later on. Therefore, we focused on one specific use case for one target audience: “A small coffee shop owner manages his business by himself and employs short term contract waiters. He needs a quick and easy way to send individual QR codes coupons to his customer base on Instagram, once or twice a week.”

We created a complete solution based on the individual user journeys of the three audiences: business owner, customers and employees.

1 . The coffee shop owner issues a QR code on the app to send to the customer

2 . The customer receives an image to show to the coffee shop employees

3 . The coffee shop employees scan the image with an iPad and get redirected to a confirmation screen

MVP development


To start, based on assumptions and Marco’s experience, we defined the target market, the audience and its current pain points.

Then, we laid down the user journey of our three target audiences, and listed the potential features at every step of the journeys. We filtered down the features and kept only the “must haves” for the MVP.

Finally, I split up the execution: one person did the UI elements and two designed two main flows. We regularly checked in order to make sure the flows were connected to each other. Finally, we each designed a set of specific screens collaboratively in Figma.

User journey for each audience and "must have" features

Screenshot of the handover file in Figma

Next steps

This MVP is due to be developed as it is, and tested with a set of potential users in Berlin. If the primary response to the product is positive, the next step will be to rework the product offering and its pricing strategy, and add features.


I enjoyed working on this start-up idea, especially as the idea answers the founder’s personal needs. Here is what I learned :

  • Organize and lead a hackathon for 2.5 days

  • Time management for team members which whom I haven't worked with before

  • Strict prioritization of features for MVP launch

  • Designing based on assumptions

  • Make decision fast

  • Handed over the concept and design to business owner and developper

Thank you for reading 👌🏼

© 2023 by Julia Marten-Deflache in Framer Sites
© 2023 by Julia Marten-Deflache in Framer Sites
© 2023 by Julia Marten-Deflache in Framer Sites