DAVID RANGEL GOMES / PRODUCT ENGINEER / CAMPINAS, BRAZIL

SIGNAL / STRUCTURE
PORTFOLIO 2026

I make complexsignals legible.

I build digital products for finance, security, and learning, connecting front-end architecture, real-time data, and interfaces that help people make decisions.

See the work View résumé — PDF

DECISION STUDY / 01Synthetic study / no live data

Latency28

Anomaly22

Confidence74

Raw input

Three readings arrive without a shared hierarchy.

SELECTED SYSTEMS / 2024—PRESENT

Selected work.
Built for decisions.

Four systems across finance, security, learning, and multi-platform architecture—each presented through the decision it had to make clearer.

01 / MANSA S.A. / 2025—PRESENT2025—present

Mansa S.A.

FRONT-END ARCHITECTURE / FINANCIAL PRODUCTS

One foundation. Three platforms.

At Mansa S.A., I work on the architecture of a multi-platform digital ecosystem across web, desktop, and mobile. The goal is a shared foundation without erasing the needs of each surface.

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DG / SYSTEM MAPWEB · DESKTOP · MOBILE

SHARED RULEStokens · interaction contracts · quality

WEBrealtime surface

DESKTOPdense workflows

MOBILEfocused actions

CONCEPTUAL MAP / NOT A PRODUCT SCREEN

02 / FINANCE · MACHINE LEARNING / 2024—20252024—2025

B3Forecast

RESEARCH INTERFACE / FORECASTING

Forecasts with context.

B3Forecast is a research interface for exploring Brazilian market history and turning LSTM experiments into an inspectable forecasting workflow.

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60%less analysis time50+ active users · <100 ms ingestion latency

B3FORECAST / MODEL VIEW CONCEPT

CONCEPTUAL VIEW / NO LIVE DATA

03 / SECURITY · REAL-TIME VISUALIZATION / 20242024

ThreatSense

NETWORK ANALYSIS / INVESTIGATION

From traffic to investigation.

ThreatSense is a real-time network analysis dashboard that turns changing traffic signals into a focused surface for observation and investigation.

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35%fewer false positivesversus rule-based systems · 5k+ labeled samples

THREATSENSE / ANALYSIS FLOW CONCEPT

THREAT STATEOBSERVEinspectable state

CONCEPTUAL FLOW / NO LIVE DATA

04 / LEARNING · ADAPTIVE PRODUCT / 20242024

StudySpark

PRODUCT DESIGN / FRONT-END / AI INTEGRATION

One study decision at a time.

StudySpark is a personalized quiz experience designed to make the next study action clear, focused, and achievable.

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STUDYSPARK / NEXT ACTION01 / 03

CHOOSE A SUBJECTWhat would you like to explore?

MathematicsHistoryPhysics

ADAPTIVE LOOP

one decision at a time

CONCEPTUAL FLOW / NO LIVE DATA

EXPERIENCE / FROM BRIEF TO OPERATION

The system continues after deploy.

I work across product definition, engineering, delivery, and the operational details that keep digital platforms useful over time.

EIXU / DIGITAL OPERATIONS

Briefing → Provisioning → Implementation → QA → Deployment → Maintenance → Improvement

CURRENT ROLEAug 2026—present

EIXU

Product Engineer & Digital Operations Lead

Leading end-to-end development and operation of the digital platform and client websites, bridging product strategy, engineering, design, and delivery.

BriefingProvisioningImplementationQADeploymentMaintenanceProcess improvement

022025—present

Mansa S.A.

Front-End Architect

Defining technical standards for a Web, Desktop, and Mobile ecosystem with React, React Native, Flutter, APIs, WebSockets, testing, and CI/CD.

React + React NativeFlutter desktopPlatform-agnostic Design SystemReal-time market dataClean ArchitectureMentorship

032022—2024

Helbass

Marketing Analyst

Worked across SEO, digital marketing strategy, PR, promotional events, and campaign production in Campinas.

+45% organic traffic+30% search rankings+25% revenue in 18 months15+ campaigns+20% team productivity

APPROACH / HOW I WORK

The interface is part of the architecture.

A technical system is only as useful as the mental model it gives the person using it. I design the model and the implementation together.

Clarity under complexity

Clarity is not removing information. It is giving each signal a position, a priority, and a next step.

Evidence before theatre

A stack is not an outcome. I show decisions, constraints, trade-offs, and contextualized metrics.

Motion with a job

Motion should explain a relationship, preserve context, or respond to an action. Otherwise, it does not ship.

PROFILE / A SHORT VERSION

Product engineer by practice.
Designer by attention.

I am David Rangel Gomes, a Product Engineer and Full-Stack Developer working where product strategy, front-end architecture, design, and delivery meet. I currently lead end-to-end digital platform and client website work at EIXU while shaping multi-platform architecture at Mansa S.A.

My independent work spans financial forecasting, security analysis, and adaptive learning. Earlier, at Helbass, I worked across SEO, campaigns, PR, and digital content, contributing to +45% organic traffic, +30% search-ranking growth, and +25% revenue growth over 18 months.

View résumé — PDF GitHub LinkedIn

CONTACT / THE NEXT SIGNAL

If the system is dense,
let's make it legible.

Talk to me about product architecture, data-rich interfaces, and creative implementation where the experience has to remain clear.

david.gomes@programmer.net

I make complexsignals legible.

Selected work.Built for decisions.

One foundation. Three platforms.

Forecasts with context.

From traffic to investigation.

One study decision at a time.

The system continues after deploy.

EIXU

Mansa S.A.

Helbass

The interface is part of the architecture.

Clarity under complexity

Evidence before theatre

Motion with a job

Product engineer by practice.Designer by attention.

If the system is dense,let's make it legible.

Selected work.
Built for decisions.

Product engineer by practice.
Designer by attention.

If the system is dense,
let's make it legible.