Open to remote roles & freelance with US and European teams

Vagner Bessa

Senior Developer & AI Engineer

I design and ship production-grade AI products and web platforms — Python & TypeScript.

Portrait of Vagner Bessa

I build smart, fast solutions end to end — from AI agents and APIs to the interfaces people use.

Remote · overlapping US & EU business hours · based in Brazil (UTC−3)

Stack & toolbox

Languages

  • Python
  • TypeScript
  • JavaScript
  • C++
  • Bash

Backend & AI

  • FastAPI
  • Django
  • aiohttp
  • Fastify
  • Mastra (AI agents)
  • LLM/RAG
  • XGBoost / ML

Frontend

  • React
  • Svelte
  • Tailwind CSS
  • DaisyUI
  • Vite

Data & Infra

  • PostgreSQL
  • Prisma
  • Docker
  • Google Cloud Run
  • Prometheus/Grafana
  • Linux
production
Agente Clínicas screenshot

Architect & lead developer

Agente Clínicas

AI-powered WhatsApp service for medical clinics

A production-grade monolith that automates patient communication for clinics over WhatsApp: scheduling, triage, emergency detection and clinic management, with full LGPD (Brazilian GDPR) compliance.

  • Multiple specialized AI agents (assistant, triage, scheduler, emergency)
  • Full WhatsApp Business integration with multi-instance support
  • LGPD compliance with audit logging and PII redaction
  • Resilience: retry with backoff, circuit breakers, rate-limit bypass for emergencies
  • Full observability stack and multi-clinic data isolation
  • Role-based React admin dashboard (clinics, patients, doctors, appointments)
  • TypeScript
  • Fastify
  • Prisma
  • Mastra AI agents
  • Baileys / WhatsApp
  • React (SPA)
  • Redis
  • Prometheus
  • Grafana
  • Sentry
active
Public-Sector AI R&D · IFCE Innovation Hub screenshot

Lead developer / ML & AI engineer

Public-Sector AI R&D · IFCE Innovation Hub

Applied ML & LLM research on public-sector financial data

An applied AI/ML research-and-development engagement at IFCE's Innovation Hub, supported by EMBRAPII, building machine-learning and LLM-based tooling for public-sector financial data. Project specifics are covered by a confidentiality agreement and are not disclosed here.

  • Applied machine learning and LLM techniques to public-sector financial data
  • Data engineering and analytical tooling on a Python / Django stack
  • Conducted within IFCE's EMBRAPII-supported Innovation Hub
  • Methods, components and results withheld under a confidentiality agreement
  • Python
  • Django
  • Machine learning
  • LLM-based tooling
  • RESTful APIs
  • uv
Project details →Private / under NDA
active
Expense Tracker AI screenshot

Solo full-stack developer

Expense Tracker AI

Conversational bookkeeping from voice notes and receipt photos

A production Django app for household finance with a PydanticAI assistant that turns plain language, voice notes and photographed receipts into categorized ledger entries — installed on Android and used daily.

  • Conversational bookkeeping — describe a purchase in plain Portuguese and the assistant resolves category, payment method and billing month before saving
  • Receipt OCR — photograph a receipt; a vision model extracts line items and Python prorates discounts deterministically so the split always reconciles
  • Voice notes — record a memo; it is transcribed and routed through the same registration flow, with media processed then discarded
  • Semantic memory — per-user rules stored as pgvector embeddings and recalled across sessions
  • Hybrid architecture — HTMX for CRUD pages, React islands for the dashboard and chat, shipped as an installable Android PWA/TWA
  • Python 3.12
  • Django 6
  • Django REST Framework
  • HTMX
  • React 18
  • Tailwind CSS v4
  • PydanticAI
  • OpenAI
  • PostgreSQL + pgvector
  • Docker
  • Google Cloud Run

Get in touch

Let's build something together

Whether you want to start a new project or need help with an existing one — for hire or for a role — I'd love to hear from you.