Backend Engineer focused on scalable systems and complex integrations.
+3 years | Java / Spring Boot | AWS | Distributed Architecture
Featured Projects
E-commerce — Monolithic Backend
Multi-tenant Spring Boot monolith powering register_flow, backoffice, ecommerce-front and field-sales app
Central backend of the B2B ecosystem. REST API powering the onboarding app (register_flow), admin panel (backoffice), B2B web SPA (ecommerce-front) and field-sales app. Layered + DDD, partner-based multi-tenant, with event streaming via Kinesis.

E-commerce Front — Multi-Tenant B2B SPA
White-label React 18 + Vite for customers and reps
B2B SPA for customers and reps to place orders. Multi-tenant white-label per partner via the `handlerpartner` header. Product browse, cart, checkout, history, delivery dates, payment plans, recommendations and custom sectoring.

Field Sales Mobile — Offline-First App
Cross-platform Flutter sales-force app with Drift (SQLite) and background sync
Cross-platform app (Android, iOS, macOS, Windows, Linux, Web) for sales reps. Customer management, orders, delivery tracking and offline sync. Clean Architecture in 3 layers (domain / infra / presentation) with 2 Dio datasources (ecommerce + integrator).

Backoffice — Admin Panel with AI Chat
Next.js 16 + React 19 with Server Components, shadcn/ui and Vercel AI SDK
Modern admin panel replacing the legacy backoffice (CRA + Ant Design). Manages integrations, customers, orders, PIX, banners and reports, with AI chat using AWS Bedrock and OpenRouter via the Vercel AI SDK.

Register Flow — Multi-Step Onboarding
Flutter onboarding app for sellers and customers with doc upload and geocoding
Multi-step onboarding app for the B2B ecosystem. Seller and customer registration with document upload, address with map, contacts and Brazilian validations (CPF/CNPJ, phone). Feature flags switch seller vs buyer flows.

Integration Platform — Client / Middleware / Orchestrator
Bidirectional bridge between Oracle Winthor and the B2B platform via 3 Java services
Three-service Java set keeping products, customers, prices, stock, orders and notifications flowing between the Oracle Winthor ERP (on-premise at the partner) and the B2B platform. integration-client runs locally, integration-middleware is the central SQS bus, and integration-orchestrator coordinates complex workflows (credit, PIX, order release, reports).

Offline Integrator — Field Sales API
Spring Boot 3.5 that generates jobs, runs partner-DB queries and feeds the offline app
Dedicated API for the field-sales app. Generates sync jobs, runs queries on the partner SEGS database (read-only) and feeds the app local Drift DB via S3. Hexagonal/clean architecture (core → application → infra), with primary PostgreSQL and secondary SEGS read-only. Dedicated infra in a separate Terraform repo.

Infra Terraform — Ecosystem AWS IaC
Terraform versioning most of the B2B ecommerce across test/hmg/prod/shared
Comprehensive IaC for the ecommerce ecosystem on AWS. Provisions Lambdas + Layers, API Gateway, RDS, S3, VPC/Subnets/SGs, SSM Parameter Store and ECR. Multi-environment (test, hmg, prod, shared) with standardized naming, remote state in S3 and CI/CD on GitHub Actions.

What I Solve
Real problems I master and solve with engineering precision
Tech Stack
Technologies I use daily to build robust applications
Backend & APIs
Mobile & Frontend
Cloud & IaC
Data & Observability
About Me
I'm from Blumenau, SC — Brazil. I joined the tech industry in 2023 with no formal CS background, learning through practice, consistency, and a lot of curiosity.
What drives me is understanding systems end-to-end: not just making things work, but knowing why that decision and not another. That's what makes me actively take part in architecture discussions, not just execute tasks.
Outside of work I'm always studying something I haven't mastered yet — distributed systems, high scalability and software architecture. I believe the best way to grow as an engineer is to expose yourself to problems bigger than the ones you solve today.
How I work
- I deliver sustainable code, not just code that works
- I take part in technical decisions with reasoning, not just execution
- I learn proactively — what I don't know today, I master before I need it
Work Experience
IT Assistant
Segala's Alimentos
Initial role focused on technical learning and development fundamentals.
Trainee Software Developer
Segala's Alimentos
Actively participated in development tasks, strengthening software engineering fundamentals.
Junior Software Developer
Segala's Alimentos
Development of more complex features with greater autonomy.
Mid-Level Software Developer
Segala's Alimentos
I develop robust and scalable solutions, focusing on quality and performance.
Senior Software Developer
Segala's Alimentos
Next step in career - building complex architectures and technical leadership.
Recommendations
I had the opportunity to work with João for the last 2 years on developing our mobile app, and I can confidently say he was a key piece in building the backend. As a Backend Developer, working with Java and Spring, João directly participated in a large part of implementing our backend structure. Additionally, he contributed significantly to improving query performance and optimizing important parts of the application, always concerned with efficiency and quality. What I like most about working with him is his attitude: he learns fast, understands problems easily, and knows how to discuss solutions maturely, always seeking the best decision for the product. He delivers quickly, but without compromising on best practices and organization, which makes a huge difference day-to-day. I recommend João with total confidence for any team that needs a solid, responsible backend developer committed to results.
João is an excellent professional, I had the opportunity to work with him for 2 years and he has always been a dedicated professional, showing from the beginning that he learns easily and is capable of taking on responsibilities. He performed excellently in the projects he participated in. João is and will be a fundamental piece in any team he works with. Therefore, I leave my recommendation for his services.
I was lucky to start my career as a developer alongside João Paulo. From the start, his competence and curiosity in problem-solving were always evident. João was a fundamental piece in my professional growth. As a colleague and friend, he never held back from helping — whether explaining something I didn't understand or dedicating hours (sometimes all day) to solve a problem together. What always mattered to him was reaching the best solution. I recommend João with full confidence to any company. Working with him is an experience that elevates everyone around.
I had the pleasure of working with João and can state, with full conviction, that his work is exceptional. I followed his evolution closely, as well as his dedication and constant drive to learn and make things happen. His role was always fundamental, both in decision-making and solution building, thanks to his deep technical knowledge and domain mastery. Working with João is, without a doubt, a valuable opportunity that everyone should have.
Real engineering, not just slides
Four interactive experiences showing how a backend engineer thinks: live metrics, incident simulator, architecture challenges and real technical learnings.
Real metrics from this portfolio: requests, latency and event feed updating every 5 seconds.
It's 3am. Payments API at 34% error rate. Every decision you make changes the metrics.
Architecture, debug, complexity and tradeoffs. Quiz with timer, score and global leaderboard.
Real technical learnings from day-to-day work — things that surprised me or changed how I think about systems.
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