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01 · SELECTED WORK · CHAPTER 01

Problems owned
end to end,

with evidence.

A selection of systems, modernizations, and products shaped from architecture through delivery.

An engineering workbench with architecture diagrams, a laptop, server hardware, and measurement tools.

ENGINEERING · SYSTEMS · DELIVERYEST. 2008

01

G2i
JAN 2026-PRESENT · Senior Software Engineer / AI Engineer

Accountable AI-native delivery

Building AI
training environments

Full-stack delivery for AI training environments, delegating code creation to AI agents while personally ensuring security, accuracy, and final delivery quality.

CHALLENGE
Deliver dependable training environments for a frontier AI lab while working across unfamiliar codebases and customer-facing workstreams.
ROLE
Senior Software Engineer / AI Engineer
APPROACH
  • Turn issue reports into complete changes across frontend, backend, APIs, and databases, then carry them through review and delivery.
  • Use repeatable benchmarks, indexing, query improvements, and regression tests to solve application and database bottlenecks.
  • Delegate code creation to AI agents in focused workstreams, then personally review and validate the result for security, accuracy, quality, and release readiness.
IMPACT
Personally owned the final quality gate for incidents, fixes, features, and customer delivery using code review, exploratory checks, automated tests, end-to-end validation, and CI.
LESSON
AI-assisted implementation accelerates delivery when the engineer remains accountable for the context, verification, and final result.
02

Aiah
2023-2026 · Senior Full-Stack Developer / AI Engineer

End-to-end AI product

Engineering with AI
LLM customer care

Resilient AI customer service on the Meta WhatsApp API, with guarded LLM replies, human handoff, and outage recovery.

CHALLENGE
Integrate Meta's WhatsApp API into customer service while preventing invented products, services, and contact numbers. The system also needed high availability and failure recovery across AWS, WhatsApp, and LLM provider outages.
ROLE
Senior Full-Stack Developer / AI Engineer
APPROACH
  • Integrated Meta's WhatsApp API with the customer-service workflow, connecting messages to LLM responses, tool calls, and human handoff.
  • Built validation and response guardrails to keep product, service, and contact information tied to real business data instead of fabricated model output.
  • Used GraphQL, asynchronous message processing, RAG with pgvector, and AWS infrastructure to support the product and its recovery paths.
  • Owned application architecture and production delivery, designing recovery behavior for AWS and external API interruptions so conversations could resume safely.
IMPACT
Delivered WhatsApp-connected AI customer service with guarded replies, validated workflows, and human handoff. During an AWS outage, no messages were lost; after AWS recovered, the system resumed and answered every message.
LESSON
Customer-facing AI needs both factual guardrails and failure recovery: a fluent reply is not enough if the information is invented or a message is lost.
03

Wolf Pro Link
2024-2026 · Senior Full-Stack Developer & AI Engineer

60% fewer runtime errors · 3× concurrent users

Modernizing an
athlete network

Wolf Pro Link connects athletes with sports professionals and managers. I prepared its application for cloud compute, built the AWS environment, and automated delivery with infrastructure as code and CI/CD.

CHALLENGE
Prepare an athlete-focused social network for cloud compute and reliable growth, while preserving availability, cost control, and the pace of product delivery.
ROLE
Senior Full-Stack Developer & AI Engineer
APPROACH
  • Migrated JavaScript to TypeScript and prepared the application and GraphQL API to run on containerized cloud compute.
  • Built the AWS environment with Docker workloads on ECS Fargate, autoscaling, Nginx and CloudFront caching, and CloudWatch monitoring.
  • Provisioned infrastructure as code with AWS CDK, created the CI/CD pipeline with GitHub Actions, and migrated AWS accounts without downtime.
IMPACT
Reduced runtime errors by 60% and supported 3× more concurrent users without increasing AWS cost, creating more capacity for athletes and professionals to connect reliably.
LESSON
A platform built around opportunity needs reliable, affordable scale as much as new features.
04

Redestina
2023-2026 · Senior Full-Stack Developer

Secure, recoverable workflows

Container transfer
coordination

Redestina coordinates container transfers between port terminals. I worked on arrival monitoring, ordered handoffs, and failure recovery while mentoring junior developers through implementation and review.

CHALLENGE
Coordinate container transfers between port terminals when arrivals, documentation, and stakeholder notifications must follow a reliable sequence with secure certificate-based access.
ROLE
Senior Full-Stack Developer
APPROACH
  • Monitored container arrivals in an external system and initiated the transfer workflow when action was needed.
  • Coordinated checks, documentation, and notifications in the required order while safeguarding certificate-based access.
  • Used DynamoDB Streams and SQS to drive downstream work and reprocess failed tasks.
  • Supported delivery through code review, engineering guidance, and junior-developer mentoring.
IMPACT
Improved container handoff reliability through ordered steps and retryable tasks, while strengthening team delivery through code reviews and mentoring junior developers.
LESSON
In logistics, reliability is a workflow property: secure access, ordered steps, and failure recovery matter as much as the happy path.
05

Rocketicons
2025-PRESENT · Co-creator & Maintainer

Selected icons, local source

Building an icon
toolkit

An open-source icon toolkit I co-created and co-maintain with a friend. Together, we built a CLI that adds selected React or React Native components as local source, with Tailwind-compatible styling and a static catalog.

CHALLENGE
Make large icon collections practical for web and native apps without forcing entire libraries into application bundles, while keeping the public catalog affordable to operate.
ROLE
Co-creator & Maintainer
APPROACH
  • Together, we built a CLI that initializes TypeScript projects and writes selected icon components into local source for review and version control.
  • We developed shared rendering utilities and Tailwind-compatible styling for React and React Native.
  • When Vercel and later AWS Amplify became too expensive for the project, we moved the localized explorer and versioned catalog to a static site on Cloudflare Pages.
IMPACT
Developers can keep only the icons they choose in their own codebase, with a consistent component API across web and native projects; the public catalog is delivered as a static site.
LESSON
For open source, architecture includes hosting economics: simplifying delivery can keep a useful project sustainable.
06

Freedom
2020-PRESENT · Senior Full-Stack Developer

Auditable paper trading

Evidence-first
paper trading

Freedom is a B3 research and paper-trading system I built around reproducible evidence. Its active momentum strategy uses completed daily data, risk controls, and a persistent simulated broker; experimental ML has no trade authority.

CHALLENGE
Turn B3 market data and trading research into reproducible paper decisions without look-ahead leakage, invented fills, or unsupported performance claims.
ROLE
Senior Full-Stack Developer
APPROACH
  • Built canonical market-data ingestion and immutable snapshots with point-in-time identity, correction history, and reproducible feature inputs.
  • Implemented a deterministic B3 momentum strategy with completed-D1 setup confirmation and backtests that separate signal quality from trade outcomes.
  • Connected approved decisions to paper-only risk controls, a persistent simulated broker, reconciliation, and idempotent replay after interruptions.
  • Kept experimental ML behind qualification gates; the current unqualified models and sealed holdout cannot drive the paper strategy.
IMPACT
Delivered an operator-runnable paper-trading path whose decisions, simulated fills, and outcomes can be traced and replayed, without claiming proven profitability or real-money execution.
LESSON
In financial systems, reproducibility, failure recovery, and an honest 'not qualified' result are product features, not obstacles to shipping.
07

Apolo Live
MAY 2023-NOV 2023 · Full-Stack Developer

Audience-led, search-visible platform

Connecting musicians
to opportunities

Built a platform where musicians could find gigs, connect, and showcase their work, shaping the web experience for slower connections and starting a shared web/mobile direction.

CHALLENGE
Help musicians find gigs, connect, and showcase their work on slower connections and modest devices, while making public content discoverable and the web/mobile experience maintainable.
ROLE
Full-Stack Developer
APPROACH
  • Owned full-stack web development using Google Cloud Platform (GCP), researched the audience's connectivity and device constraints, and used the findings to guide a responsive interface without a dedicated UI/UX specialist.
  • Improved loading and perceived responsiveness with lazy loading, BlurHash image placeholders, and loading skeletons.
  • Implemented server-side rendering for search-visible public content while retaining interactive application behavior and supporting the advertising model.
  • Initiated a migration from Flutter to React Native to share code across web and mobile and address functionality drifting between platforms.
IMPACT
Delivered a musician platform shaped by real audience constraints, with faster-feeling loading, search-visible public content, and a path toward more consistent cross-platform delivery.
LESSON
Audience research should shape engineering decisions: performance, discoverability, usability, and maintenance capacity are connected product concerns.
08

Ceros
JUL 2019-APR 2023 · Senior Full Stack Developer / Senior Software Engineer

More accessible, maintainable platform

Modernizing a
creative platform

Modernized Ceros’s creative SaaS platform across API architecture, React interfaces, accessibility, testing, and delivery tooling.

CHALLENGE
Modernize an enterprise creative SaaS platform while improving accessibility, platform reliability, and the maintainability of a large existing system.
ROLE
Senior Full Stack Developer / Senior Software Engineer
APPROACH
  • Co-owned analysis and trade-offs for a message-driven NestJS API architecture; made API documentation enforceable with TypeScript decorators and ESLint.
  • Migrated legacy Backbone.js components to React and improved keyboard and screen-reader access across customer-created interactive content.
  • Standardized Docker development environments, optimized Jenkins and container builds, and supported the Fastly-to-Cloudflare migration with Terraform.
  • Expanded unit, integration, and end-to-end testing, researched scalable collaboration, and mentored engineers through platform changes.
IMPACT
Strengthened the platform's foundations with clearer API contracts, more accessible interfaces, broader test coverage, and more repeatable development and delivery workflows.
LESSON
Enterprise modernization works when architecture, accessibility, delivery tooling, and team practice evolve together.
09

Crossover
FEB 2016-JUN 2019 · Front End Developer / Software Architect

Modernized systems and delivery

Modernizing enterprise
applications

Modernized a legacy HR platform, integrated IBM Watson into education, and made delivery more repeatable through CI/CD, containers, and Azure infrastructure research.

CHALLENGE
Keep enterprise applications moving while replacing aging technology foundations and making delivery and infrastructure more repeatable.
ROLE
Front End Developer / Software Architect
APPROACH
  • Led an Adobe Flex-to-AngularJS migration for a legacy HR platform and integrated IBM Watson into an educational application.
  • Implemented CI/CD workflows and Docker-based environments for applications and databases.
  • Validated IIS and Microsoft SQL Server workloads in Windows containers, creating evidence for a lower-cost shared Azure infrastructure approach.
IMPACT
Modernized foundations and delivery practice across internal and client-facing systems while improving maintainability and infrastructure utilization.
LESSON
A proof of concept is most useful when it turns a disputed infrastructure direction into an informed decision.
10

Level Up Games
FEB 2008-FEB 2016 · Lead Developer

High-traffic platform and team growth

Building game-publishing
platforms

At Brazil’s then-largest online-game publisher, I led a six-person team and made dedicated servers more efficient under thousands of simultaneous requests.

CHALLENGE
At what was then Brazil's largest online-game publisher, keep a site on self-managed dedicated servers responsive under thousands of simultaneous requests while leading a six-person engineering team.
ROLE
Lead Developer
APPROACH
  • Delivered and modernized web, e-commerce, billing, payment, and large-file delivery systems using PHP, .NET, AngularJS, and Yii.
  • Built the CMS that gave editors access to site content, worked closely with marketing to launch campaigns, and delivered an early banner-serving system for the game websites.
  • Owned web architecture across SEO, accessibility, responsive and mobile-first development, and performance measurement with Google Analytics, Tag Manager, PageSpeed Insights, and Core Web Vitals.
  • When I arrived, the web farm ran only Apache. I put Tux in front of it, then later moved to Varnish with Nginx to serve heavy traffic more efficiently; I also tuned the backend and added monitoring and incident-response integrations.
  • Introduced Jenkins CI and blue-green deployment practices; mentored engineers through reviews, training, SOLID principles, and testing.
IMPACT
Made self-managed servers more efficient under thousands of simultaneous requests while sustaining editorial publishing, campaign delivery, reliable releases, and the growth of a six-person team.
LESSON
Leadership is holding the product, the operating system, and the growth of the team in view at the same time.
11

Consoft
Infrastructure Support / Web Development

Infrastructure-to-software foundation

Infrastructure
and software

At Consoft, supported São Paulo State Department of Finance infrastructure and built a PHP/MySQL process-status tool across a mixed server and network environment.

CHALLENGE
Keep public-sector IT services running across mixed server and network environments while modernizing systems and building internal tools for operational needs.
ROLE
Infrastructure Support / Web Development
APPROACH
  • Supported the Windows NT-to-Windows 2000 Server migration and administered Windows domains and Active Directory.
  • Implemented and maintained Linux DNS services, supported Solaris email systems, and troubleshot TCP/IP connectivity, network security, and user issues.
  • Built a PHP and MySQL application for tracking process status, linking software delivery to day-to-day business and infrastructure requirements.
IMPACT
Supported essential infrastructure and delivered an internal process-tracking tool while gaining practical experience across servers, networks, operating systems, and applications.
LESSON
Understanding deployment environments and failures across system boundaries became the foundation for my later work in software architecture, DevOps, infrastructure as code, and CI/CD.

END OF THE CASE STUDIES

The rest of the story lives in the journey.

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