Rafard, São Paulo, Brazil
I don't split systems into frontend or backend in my head. I think about the whole system: business model, architecture, data flow, infrastructure, security and cost. At IBBX, I led the migration from scattered microservices to a modular TypeScript monorepo, introduced DDD/Clean Architecture across services, and migrated performance-critical workloads from Node.js to Go. I also investigated a $3,500/month Aurora PostgreSQL cost spike caused by 421 million sequential scans reading 48 trillion rows, reducing critical queries to 0.056ms and confirming ~$9,600/year in savings. Outside work, I built BatAudit, a self-hosted audit logging platform in Go with SDKs, CLI, dashboard and distributed architecture. My current focus is distributed systems, observability and infrastructure engineering.
Led the migration from scattered microservices to a modular TypeScript monorepo using Turborepo + pnpm workspaces, introducing DDD and Clean Architecture across all services. Migrated performance-critical workloads from Node.js to Go, leveraging goroutines for concurrent processing and reducing AWS Lambda cold start times. Investigated a $3,500/month Aurora PostgreSQL cost spike caused by 421M sequential scans reading 48T rows, reducing critical queries to 0.056ms and confirming ~$9,600/year in savings. Built distributed event-driven workflows on AWS using Lambda, SQS, SNS and DynamoDB for industrial IoT processing pipelines. Designed and operated industrial IoT data pipelines using MQTT, TimescaleDB and downstream ML-based analysis services. Implemented distributed tracing and observability workflows with OpenTelemetry, Jaeger, Datadog and Grafana. Replaced manual AWS operations with Pulumi Infrastructure as Code and migrated CI/CD from AWS CodePipeline to GitHub Actions. Built a typed database layer with Kysely + kysely-codegen, automatically regenerated in CI and published through AWS CodeArtifact. Developed internal frameworks and SDKs in TypeScript, including feature flag tooling and automated OpenAPI/codegen workflows.
Full-stack developer in an industrial environment, built and maintained web applications with React.js, REST APIs with Node.js, and mobile apps with React Native. Managed relational databases across SQL Server, Oracle, and PostgreSQL, including procedures, views, and triggers. Also built internal desktop tooling with Electron and contributed to the company's Design System. Worked with monorepo structure and automated testing with Jest and Testing Library.