GRIDSERVE - Designing Fraud Prevention at Scale

/Role

Lead Product Designer — risk-informed UX, authentication flows, validation patterns, user messaging, and delivery handover.

/Context

Fraud prevention across a live charging journey, balancing business protection with a low-friction experience for genuine users.

/Impact

Reduced fraudulent charging activity while protecting legitimate user completion and improving trust in a risk-sensitive journey.

Redesigned charging flow

Redesigned charging flow introducing pre authentication and card holds, directly reducing fraudulent transactions.

/The challenge

Fraudulent charging activity was increasing among GRIDSERVE app users, impacting revenue, operational cost, and customer trust. The challenge was to introduce stronger authentication without increasing friction or negatively affecting legitimate users.

/Team

Set the UX strategy and authentication design direction, working directly with iOS and Android engineers through iterative delivery and into QA. Partnered with product management and client stakeholders to align on scope, escalate business policy decisions, and maintain design integrity through to release.

Revenue loss trend analysis

Revenue loss trend analysis identifying fraud patterns and shaping the authentication strategy.

/The approach
  • Risk Analysis — Analysed fraud patterns and behavioural data to identify weaknesses in the existing charging flow, pinpointing where abuse was occurring.
  • Pre Authentication Strategy — Designed a pre authentication layer within the charging journey, validating intent before high risk actions could occur.
  • Behavioural UX Refinement — Redesigned hold logic to align with real user behaviour, reducing unnecessary repetition while maintaining security controls.
/Project challenges
  • Balancing Security and Usability — Strengthened authentication without introducing unnecessary friction or abandonment.
  • Stakeholder Sensitivity Around Risk — Aligned product, engineering, and business stakeholders around a solution that protected revenue without harming conversion.
  • Behavioural Edge Cases — Designed flows that accounted for misuse patterns while preserving clarity for legitimate users.
Measurable decline in fraudulent revenue

Measurable decline in fraudulent revenue after introducing pre authentication.

/How did I have an impact?

Working from a brief grounded in engineering and product data, I set the design direction for a pre-authentication strategy — defining where in the charging journey intervention should sit to reduce risk without affecting legitimate users.

Led the end-to-end design of the authentication flows in close partnership with iOS and Android engineers, ensuring the solution was technically grounded and behaviourally sound.

In stakeholder discussions around hold amount, I advocated for a user-controlled input to reduce friction. Through structured deliberation, we established that implementation complexity and UX clarity favoured a fixed amount — the right call, made collaboratively and documented clearly.

Payment flow redesigned

Payment flow redesigned to introduce pre authentication and reduce risk.

/Outcomes

Near-eliminated in-app credit and debit card fraud, closing a vulnerability that had allowed users to charge without valid payment and directly impacting revenue recovery.

Session completion rates held stable following the introduction of pre-authentication, confirming the added friction was proportionate and well-positioned within the journey.

Established as a major internal win, with the authentication approach becoming a foundational part of GRIDSERVE's payment security strategy.

Surfaced a clear business policy decision around hold amount — user feedback indicated the fixed value felt high. Design's role was to identify and escalate the tradeoff. The decision on amount was correctly returned to the business to own.