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I'm Luiz Carlos de Castro Júnior, a results-driven Full-Stack Developer and AI Engineer with hands-on experience designing and delivering scalable web applications, modernizing legacy architectures, optimizing databases, and integrating Large Language Models (LLMs) and Vector Databases to solve complex business challenges. I have a strong track record of remote collaboration and delivering impactful solutions, including an enterprise logistics simulator that reduced planning time for Petrobras. I'm passionate about clean code, test-driven development (TDD), and leveraging AI to drive operational efficiency.…I'm Luiz Carlos de Castro Júnior, a results-driven Full-Stack Developer and AI Engineer with hands-on experience designing and delivering scalable web applications, modernizing legacy architectures, optimizing databases, and integrating Large Language Models (LLMs) and Vector Databases to solve complex business challenges. I have a strong track record of remote collaboration and delivering impactful solutions, including an enterprise logistics simulator that reduced planning time for Petrobras. I'm passionate about clean code, test-driven development (TDD), and leveraging AI to drive operational efficiency.

Luiz Carlos de Castro Júnior

Full Stack Developer, Web Developer, Programmer, +5

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I'm Luiz Carlos de Castro Júnior, a results-driven Full-Stack Developer and AI Engineer with hands-on experience designing and delivering scalable web applications, modernizing legacy architectures, optimizing databases, and integrating Large Language Models (LLMs) and Vector Databases to solve complex business challenges. I have a strong track record of remote collaboration and delivering impactful solutions, including an enterprise logistics simulator that reduced planning time for Petrobras. I'm passionate about clean code, test-driven development (TDD), and leveraging AI to drive operational efficiency.…I'm Luiz Carlos de Castro Júnior, a results-driven Full-Stack Developer and AI Engineer with hands-on experience designing and delivering scalable web applications, modernizing legacy architectures, optimizing databases, and integrating Large Language Models (LLMs) and Vector Databases to solve complex business challenges. I have a strong track record of remote collaboration and delivering impactful solutions, including an enterprise logistics simulator that reduced planning time for Petrobras. I'm passionate about clean code, test-driven development (TDD), and leveraging AI to drive operational efficiency.

Available to hire

I’m Luiz Carlos de Castro Júnior, a results-driven Full-Stack Developer and AI Engineer with hands-on experience designing and delivering scalable web applications, modernizing legacy architectures, optimizing databases, and integrating Large Language Models (LLMs) and Vector Databases to solve complex business challenges. I have a strong track record of remote collaboration and delivering impactful solutions, including an enterprise logistics simulator that reduced planning time for Petrobras.

I’m passionate about clean code, test-driven development (TDD), and leveraging AI to drive operational efficiency.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Language

Portuguese

Fluent

English

Advanced

Spanish; Castilian

Intermediate

Work Experience

Full-Stack Engineer & AI Consultant at ARS MACHINA CONSULTANCY

September 1, 2025 - Present

Leading architecture and development across enterprise-grade applications, delivering scalable full-stack solutions and AI-enabled features. Tasks include system design, hands-on development, and strategic technology guidance to transform complex ideas into high-impact technology products.

Full Stack Developer at EY

December 1, 2022 - September 1, 2025

Helped develop a mission-critical enterprise logistics simulator for Petrobras, enabling complex fleet planning scenarios and improving operational efficiency. Implemented a high-performance bidirectional CSV processing engine (Ngx-PapaParse) to offload heavy data transformations to the client side, reducing server overhead. Modernized core modules of a legacy Java/JSF ecosystem by migrating to a decoupled Angular/Spring Boot architecture while maintaining 100% uptime; optimized PostgreSQL queries and backend logic to reduce latency and improve data accuracy for decision-makers.

Software Engineer at VarejOnline - Sistema de Gestão Empresarial

August 1, 2021 - October 1, 2021

Accelerated digital transformation of a legacy ERP, migrating from ActionScript/Java EE to a high-performance Angular 9 and Spring Boot architecture for large-scale retail and wholesale operations. Refactored service order management modules, applying SOLID principles and design patterns to enhance extensibility and reduce bottlenecks.