I'm a Senior Full-Stack Engineer based in Brazil, with 6+ years in software development and a broader technology background since 2010. I build backend-heavy products with Python/FastAPI and Node.js, and close the loop with React/Next.js and TypeScript.
My recent work spans applied AI and evaluation, reliable event delivery, realtime collaboration and self-hosted infrastructure. I care about measurable behavior, explicit trade-offs and owning systems from requirements through deployment.
🟢 Open to an exclusive, long-term full-time remote role through an international contractor agreement.
- rag-evals — Python/FastAPI RAG system with hybrid pgvector + FTS retrieval, a labeled golden set, answer-quality evaluation, cost/latency tracking and a CI regression gate.
- webhook-relay — reliable webhook delivery in Go with a Postgres ledger, Redis Streams, retries, DLQ, circuit breaker and OpenTelemetry; its chaos test delivered 14,399/14,399 events with zero lost.
- realtime-board — offline-first collaborative kanban with Next.js, TypeScript and Yjs CRDT, backed by convergence, offline-merge, multiplayer E2E and accessibility tests.
- Bruce open-source contribution — merged upstream C++ fix for a reproducible ESP32 heap-corruption crash, root-caused from device logs and validated on M5Stack Cardputer + CC1101 hardware.
- Backend: Python · FastAPI · Node.js · PostgreSQL · Redis · WebSockets
- Frontend: React · Next.js · TypeScript · Vue/Nuxt · Tailwind CSS
- AI / LLM: RAG / retrieval · evaluation · multimodal workflows · multi-provider integrations
- Infra: Docker · Ansible · Proxmox · CI/CD · OpenTelemetry
More product work — including traderOS, Books and my homelab — is documented at leonidasamaro.com.