> hello_world
Moises Costa
Senior Full Stack Engineer
13+ years modernizing legacy systems into modern, AI-powered platforms. React, TypeScript, Node.js, Python — and currently adopting Golang.
Building bridges between legacy and modern
I started my career at 19, passing one of Brazil's competitive public service exams to join DETRAN-RJ — the state's Department of Motor Vehicles, serving millions of citizens. That exam taught me something fundamental: I can learn anything fast.
Over 13 years, I evolved from IT support to Senior Full Stack Engineer. I specialize in a very specific challenge: modernizing decades-old legacy systems without causing downtime. I build API layers with Node.js that connect old relational databases to modern React frontends — using the Strangler Pattern to ensure zero risk.
Today, AI is central to my workflow. I use Claude Code and Copilot for productivity, and I integrate LLM APIs into my applications. I've created 35 AI Spaces and 22 datasets on HuggingFace. I'm currently adopting Golang for high-performance microservices.
Quick Facts
Tools I build with
From frontend interfaces to backend APIs, databases, and AI integrations — a full-stack toolkit refined over years of real-world problem solving.
Frontend Architecture
React with TypeScript, Zustand for client state, React Query for server state. Lazy loading and virtualization for performance. Tailwind CSS for rapid, consistent styling.
Backend & APIs
Node.js + Express for REST APIs. Python + FastAPI for AI services. Currently adopting Golang for concurrent, high-throughput microservices with goroutines.
Data & Infrastructure
PostgreSQL as primary database. JSONB for flexible schemas. Docker for containerization. Event-driven architecture with message queues for decoupled services.
AI Integration
Full LLM pipeline: prompt engineering, token management, JSON response parsing. Claude API, OpenAI API, HuggingFace. 35 AI Spaces, 22 datasets published.
A 13-year journey
IT Technician
Santa Mônica Centro Educacional — Bento Ribeiro
First professional experience in IT. Hardware maintenance, network support, and technical assistance for educational institution. Built the foundation for a career in technology.
IT Support Specialist
DETRAN-RJ
Passed one of Brazil's competitive public service exams at age 19. Hardware support, Windows administration, and first exposure to large-scale government IT infrastructure.
Multi-Department IT Analyst
DETRAN-RJ
Rotated through Ombudsman, Education, and Internal Affairs departments. Gained deep understanding of cross-departmental workflows and legacy system pain points.
Bachelor's in Marketing
Universidade Estácio de Sá
Developed strategic thinking, communication skills, and data-driven decision making. The marketing background provides a unique perspective on user experience and product design.
Full Stack Developer
DETRAN-RJ
Transitioned to software development. Built first React applications and Python automation scripts to overcome limitations of legacy interfaces.
Senior Developer
DETRAN-RJ
Adopted Node.js for backend APIs. Implemented the Strangler Pattern to modernize legacy databases without downtime. Built the Asset Management Dashboard.
Senior Full Stack Engineer
DETRAN-RJ
Focus on API integration and system modernization. Connected legacy relational databases to modern React frontends through RESTful API layers.
AI-Augmented Developer + Post-grad Student
DETRAN-RJ & Estácio de Sá
Deep AI integration: Claude Code, Manus AI, GitHub Copilot. Created 35 AI Spaces and 22 datasets on HuggingFace. Currently pursuing Post-grad in Big Data & Data Analytics (Mar/2025 – Dec/2026) and adopting Golang.
Things I've built
Asset Management Dashboard
Interactive dashboard for DETRAN-RJ asset inventory with KPI cards, filterable tables, and data visualizations. Built with React, TypeScript, and Tailwind CSS.
Agente DETRAN-RJ
AI-powered assistant for DETRAN-RJ processes. Integrates with SEI (Electronic Information System) for automated document processing and workflow optimization.
SEI Document Extractor
Batch automation tool for extracting processes from SEI-RJ. Downloads PDFs, extracts metadata, and manages download queues for government documents.
MSC Consultoria Platform
Full-stack consulting platform with client management, project tracking, and automated reporting. Built for a consulting firm serving public sector clients.
AI is not a buzzword for me
I integrate AI at two levels: as a productivity multiplier in my daily workflow (Claude Code, Copilot) and as a feature layer in my applications (LLM APIs, prompt engineering, token management).
35
AI Spaces
22
Datasets
Let's connect
I'm actively looking for new opportunities in fast-paced, AI-centric environments. Whether you have a position, a project, or just want to chat about tech — reach out.