Fintech B2C Project (11/2025)

How I built the first sales-financing audit layer for a platform used across 1,597 stores after a real fraud incident

Client : A global leader in telecommunications and mobile devices

Role

UX/UI Designer

Duraction

9 days

Responsibilities

Information Architecture
UX Strategy

Design decisions
high-fidelity prototype

Context

The product is a financing platform that allows partner stores to sell mobile phones to end customers through installment plans.

Problem

Salespeople were altering the final price of a product below the allowed minimum, closing the sale, and then registering the transaction under a different salesperson’s national ID (CPF) erasing any trace of who had actually made the unauthorized change.

Business/security layer

Without reliable authorship tracking, prices could be manipulated and the action hidden behind another employee’s identity active fraud with direct financial impact.

Process

Arquitetura de Informação

Mapped out the current usage flow and identified the exact weak point: the total dependency of the administrator to enter each salesperson's password and password recovery email address into the system.

See FigJam

Design Decision

On first login (Flow 1) , the salesperson is guided through a flow to create their own password in the Flow 2 , removing the need for admins to create and distribute individual passwords for every employee and password recovery in the Flow 3.

To enhance security and ensure the user’s identity during the audit, I decided that the password should be requested at three points in the process:
1- upon initial access, 2- when editing the product price, and 3- when signing the contract.

Strategy to implement as soon as possible

the project was triggered by an active fraud attempt the solution had to be designed and shipped quickly to contain the risk.

The implementation strategy that would be rolled out in phases and on a set schedule, so as not to disrupt sales and to allow users to complete the process at their own pace, recognizing that users need time to adapt.

Prototype

I built the full flow as a high-fidelity prototype in Figma, covering first-time login and self-service password creation.

See Figma

Solution

Each salesperson to have a unique, verifiable identity in the system (ID number + self-created password)

1- Initial access

2 - Editing the product price

3- Signing the contract.

Results & Impact

Eliminating the manual creation of passwords saved approximately 800 hours of administrative work
(nearly 100 business days)

100% of sales registered in the system became traceable back to the salesperson who executed.

The business stakeholder validated the outcome directly in a presentation meeting:

Captura de Tela 2026-07-21 às 23.23.54.png

Results at a glance

Captura de Tela 2026-07-21 às 23.21.33.png

Key Learnings

This project taught me how to design under real pressure: with an active fraud case in progress, response time mattered as much as solution quality.

Delivering in 9 days meant making fast decisions with the business stakeholder as the primary validation point, rather than the fuller end-user research process I’d typically pursue.

How I identified that an exposed financing value on the interface revealed the profile of 76,800 customers & how I brought the product into data protection compliance

GravacaodeTela2025-01-06as02.21.31-ezgif.com-video-to-gif-converter (1).gif

How I built the first sales-financing audit layer for a platform used across 1,597 stores after a real fraud incident

Role

Duraction

Responsibilities

Information Architecture

UX Strategy

Design decisions

high-fidelity prototype

Context

The product is a financing platform that allows partner stores to sell mobile phones to end customers through installment plans.

Problem

Salespeople were altering the final price of a product below the allowed minimum, closing the sale, and then registering the transaction under a different salesperson’s national ID (CPF) erasing any trace of who had actually made the unauthorized change.

Business/security layer

Without reliable authorship tracking, prices could be manipulated and the action hidden behind another employee’s identity active fraud with direct financial impact.

Process

Arquitetura de Informação

Mapped out the current usage flow and identified the exact weak point: the total dependency of the administrator to enter each salesperson's password and password recovery email address into the system.

Design Decision

On first login (Flow 1) , the salesperson is guided through a flow to create their own password in the Flow 2 , removing the need for admins to create and distribute individual passwords for every employee and password recovery in the Flow 3.

To enhance security and ensure the user’s identity during the audit, I decided that the password should be requested at three points in the process: 1- upon initial access, 2- when editing the product price, and 3- when signing the contract.

Strategy to implement as soon as possible

the project was triggered by an active fraud attempt the solution had to be designed and shipped quickly to contain the risk.

The implementation strategy that would be rolled out in phases and on a set schedule, so as not to disrupt sales and to allow users to complete the process at their own pace, recognizing that users need time to adapt.

Prototype

I built the full flow as a high-fidelity prototype in Figma, covering first-time login and self-service password creation.

Solution

Each salesperson to have a unique, verifiable identity in the system (ID number + self-created password)

1- Initial access

2 - Editing the product price

3- Signing the contract.

Results & Impact

Eliminating the manual creation of passwords saved approximately 800 hours of administrative work (nearly 100 business days)

100% of sales registered in the system became traceable back to the salesperson who executed.

The business stakeholder validated the outcome directly in a presentation meeting:

Results at a glance

Key Learnings

How I identified that an exposed financing value on the interface revealed the profile of 76,800 customers & how I brought the product into data protection compliance

To enhance security and ensure the user’s identity during the audit, I decided that the password should be requested at three points in the process:
1- upon initial access, 2- when editing the product price, and 3- when signing the contract.

Eliminating the manual creation of passwords saved approximately 800 hours of administrative work
(nearly 100 business days)