CASE STUDY - UX / interaction design
Scaling Mejuri Membership
dcbel builds a smart home energy system that manages solar, electric vehicle battery, backup energy storage, and grid power from a single wall-mounted unit. Its interface failed during real internal field testing during a blackout. I led the redesign, and it shipped on time.
Design strategy
Usability testing
Mobile interaction design
Design systems
Stakeholder presentation
01 -
Context & challenge
With over 2 million shoppers, the loyalty program had fewer than 1 million members, even though it was free. Most high spenders still checked out as guests.
The guest checkouts left Mejuri's highest-value customers invisible to its retargeting and loyalty infrastructure. The business wanted to close the gap with a time-limited summer promotion. A free piece of jewellery for joining Mejuri+ at the point of highest purchase intent.
My mandate was to design that intervention and ensure it brought in new memberships.
how might we
How might we convert high-spending guest shoppers into Mejuri+ members at checkout without disrupting the checkout flow?
70% of testers converted
The winning concept, validated with 20 screened participants, overturned my own hypothesis.
1M+ members
Mejuri+ surpassed 1 million active members during the one-month promotional period.
02 -
Strategy: designing to test, not to be right
I built three architecturally distinct concepts so that testing would resolve the hypothesis rather than individual preferences.
No matter the company or the team, we usually fall into our biases. I had to push back on the opinions of my seniors and colleagues. The only way to do it was to back it up with data.
CONCEPT 1
Progressive upselling
A step-by-step guide breaking the offer into stages, reducing overwhelm through incremental accomplishment at each threshold.
CONCEPT 2
Free jewellery card
The offer placed directly below cart items, previewing the reward next to the price. My personal prediction for the winner.
CONCEPT 3
Membership bar
A persistent bar pinned to the top of the cart, separating the membership goal from transactional detail, with persuasive copy and one unambiguous CTA.
03 -
Interaction design: the membership bar
One component, four states, each with distinct copy and treatment across the guest-to-member journey.
Some of the components weren't designed from scratch. I reused existing components from the design library and extended it with a line of copy but no structural change. That saved prototyping time and kept the cart consistent with the current look.
Mejuri's design system was built on WCAG AA foundations. I audited my design additions with Lighthouse and a contrast checker. All components met AA contrast and touch-target sizing requirements.
04 -
Validation: usability testing
Users felt the Free Jewellery and Free Shipping messages competed for attention, diluting each's value.
I ran unmoderated tests with 20 participants, with participants screened to match the target profile of high-spending guest shoppers not currently enrolled in Mejuri+.
The results overturned my assumption. I designed Concept 2 believing users wanted the reward beside the price, while my colleagues favoured Concept 1.
Concept 3, however, converted 70% of participants. Separating the membership goal from the transactional cart detail removed the message competition and made the CTA unambiguous.
05 -
Systems thinking: designing for scale
The most consequential decision wasn't just the copy or the placement, it was building a system component.
Using the newly launched Figma feature, I created variants for each user state and journey stage so a future designer or marketer could deploy a new offer without a developer or a redesign.
08 -
Lessons learned
LESSON 01
Be wrong fast
I was convinced Concept 2 was right, while my colleagues were convinced Concept 1 was right. Building three distinct concepts and testing them before committing meant the data made the call, not assumptions.
LESSON 02
Campaign thinking vs. system thinking
The immediate instinct is to design for the moment. The better decision is to design for what comes after. Scaling the component library and keeping it up to date with industry standards helped the business gain velocity.
LESSON 03
Separation reduces cognitive load