Senior Product Designer

GusCarneiro

I build paths for others to follow.
Product designer for regulated, high-volume products and the systems underneath them. Most recently, payments, acquisition and a multi-brand design system at KTO.

6+
Years designing
6
Design systems built
33
Engineers using a design system I rebuilt
83%
Faster deposits with Pix Biometrics
View case studies →About me

Selected work

Six projects that follow the player's money

At KTO, I followed it from the first visit to the last deposit. I designed the first thing visitors saw, gave players one place to manage their account, made deposits faster, designed a way to recover the deposits players abandoned and pushed for protections for players at their most vulnerable, with the design system I rebuilt underneath all of it.

01Pix Biometrics

Turning a two-minute deposit into a twenty-second glance

A biometric Pix deposit for KTO's players. An A/B test showed where not to offer it, and that rule spread beyond Payments.

83%
faster deposit completion

Scope

Fitting a new payment method into a habit without breaking itTurning a failed test into a rule other teams followed
A/B TestingOpen FinancePayment Flows

02ACE Design System

Building KTO's design system to scale across brands and themes

I rebuilt KTO's design system from a design-only Figma library into 55 components in production, with a four-layer, multi-brand and multi-theme token architecture on web and Flutter.

6 squads, 33 engineers
on web and Flutter

Scope

Separating brand and theme from component logicScaling component production from one designer to three
Token ArchitectureTokens StudioDesignOps

03Responsible Gambling Limits Hub

Limits should be invisible when things are fine and firm when they aren't

One hub where players see every limit, what's left and when it resets, with warnings before a player reaches a limit and a 24-hour cooling-off period to loosen one.

−66%
limit-related support per player

Scope

Balancing player protection against conversionDesigning for players who are fine today and at risk tomorrow
User ResearchBenchmarkingJobs to Be Done

04Payment Link + Pix Multichannel

Recovering unfinished deposits

A payment link project that data and a regulatory risk turned into a plan to recover abandoned Pix deposits.

83.75%
of failed deposits were abandoned, not rejected

Scope

Running a cross-team risk workshop before engineering committedMoving the project to where the data showed deposits were lost
Funnel AnalysisRisk AnalysisLifecycle Messaging

05Logged Out Environment & CMS

Landing page changes shouldn't wait for the next product sprint

KTO's logged-out site, rebuilt as a standalone product that Marketing and SEO could run on their own.

15.9% → 24.2%
organic click-through rate

Scope

Splitting the logged-out site from the product so Marketing could run itDesigning components that hold any content Marketing puts in them
CMS DesignSEOLanding Page Optimization

06My Account Redesign

A page every team added to and nobody had designed

A catch-all menu turned into a place to manage money and identity, with pending items surfaced before a withdrawal fails. Six weeks of planned validation, compressed into two.

Shipped
September 2026

Scope

Redefining My Account as account management, not product discoveryChoosing what to validate when the World Cup cut six planned weeks to two
Information ArchitectureHypothesis MappingScope Prioritization

Personal project

Product Gears

A roadmap tool that shows customers what happened to their feedback. Co-founded in 2021, launched, and used by Agenda Edu with its teams and customers.

User InterviewsUsability TestingB2B SaaS

I design beyond the screen.Most of my projects carry a piece of how I work: a framework, a component or a pattern other teams kept using.

Design system sandbox

An example of how I build design systems

Switch themes and brands and interact with real components backed by a live token system. Hover (on desktop) or tap (on mobile) any component to see its full token chain.

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Essays

I write on what I'm passionate about in product design

Essays on design systems, product thinking and the ideas behind how we work.

A tomato with a paper tag tied to its stem that reads 'NOT A VEGETABLE,' against a mustard-yellow background.

September 1, 2026

Component Is a Vegetable Word

Design and engineering use 'component' to mean different things. That imprecision has a real cost, and naming it changes how you build.

A Fibonacci spiral diagram overlaid on a plate of breaded fried food, with the text 'this is not science' traced along the spiral curve.

August 10, 2026

The Design Principle You Defended Last Week Probably Wasn't Science. Neither Was Mine.

Design conventions like the three-click rule and the golden ratio feel scientific, but the evidence rarely holds up. Here's what that costs you.

Side-by-side comparison of a green circular loading spinner labeled 'This is an elevator button' and a dark skeleton screen card labeled 'This is a Minecraft world.'

May 25, 2026

Skeletons and Loadings Have Everything to Do With Elevators and Minecraft

A convention that the design community adopted without ever testing it.

View all essays→
Gustavo Carneiro

About me

Carneiro/ kɐɾˈnejɾu /  ·  n.  ·  Portuguese for ram, which originated as an occupational name for a shepherd, the one that guides the flock.

I'm a product designer based in Fortaleza, Brazil, and I've worked remotely for my whole career. Until KTO closed in October 2026, I was the only designer in its Payments & Compliance squad and owned the design side of ACE, the multi-brand design system used by six product squads.

Before that, I designed products at a legal tech and an HR tech startup, and at an iGaming media company, from research to interface. Working on both sides, the product and the system under it, is what makes my work hold up in the field.

LinkedInResume

Hiring?I'm open to remote Staff and Senior IC product design roles.

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