Open to opportunities

Lucas Oliveira User

@lucasoliveirauser

Message

I build production AI agents and full-stack SaaS products that ship end-to-end.

Brazil

Message

What I'm looking for

I’m looking for freelance/contract or full-time AI & SaaS engineering work where I can ship production systems—owning cost control, logging, fallbacks, usage limits, and real-path testing—so LLM ideas turn into paying users.

I’m a founder and full-stack / AI engineer based in São Paulo, shipping AI that goes from prompt to paying users. I build and run live, multi-tenant SaaS end to end—multiple apps, a 443-endpoint REST API, and 14 AI features—with an AI agent that operates the entire product over WhatsApp.

I engineer agents for production reliability, not demos: function-calling across 12+ tool domains, vision, memory, RAG, multi-LLM routing, provider fallback, and per-call cost logging with usage limits. I also create voice AI for realtime speech-to-text and meeting bots for Google Meet / Teams / Zoom, turning meeting and audio into structured, human-reviewed reports.

Experience

Work history, roles, and key accomplishments

Current

Full Stack & AI Developer

Current

Freelancer

Jan 2024 - Present (2 years 6 months)

Provided end-to-end development for full-stack and AI projects using React, TypeScript, and FastAPI, integrating multiple AI models. Built LLM API orchestration for data extraction and contextual automation workflows, delivering MVPs such as WhatsApp systems and ERP/academic assistant solutions.

React TypeScript fastAPI API Orchestration Data Extraction Automation RAG Prompt Engineering AI Agents Machine Learning React Native

Current

Freelancer — Full Stack & AI Developer

Current

Freelancer

Jan 2024 - Present (2 years 6 months)

• End-to-end development with React, TypeScript, Pthon (FastAPI) and multiple AI models
• Intelligent rocess automation: LLM API orchestration, data extration, contextual decision flows
• Functional MVPs deivered: WhatsApp systems, ERP platforms, academic asistants, AI video generation
• Cognition SP Hackatho — 2nd place (Agora AI track) and 3rd place (Oracle rack), invited to pitch at Oracle

Retrieval Augmented Generation (RAG)React Native Prompt Engineering Agentes De IA Aprendizado De Máquina

Automation Developer

Loja NaPassarela

Jan 2023 - Dec 2023 (11 months)

• Identified a bottleneck in product registration nd built LojaSync (FastAPI + React/TS) — an end-to-ed automation system integrated with ByteEmpresa ERP
Reduced registration time through intelligent PDF dta extraction and desktop automation with PyAutoGUI nd WebSockets
• Batch editing, product grid handling and native ByteEmpresa ERP integration