Renato Ferreira

Founder & Lead Engineer

Mar 2024 - Present • 2 yrs 2 mos

Founder and lead engineer of Ousianic, a technology studio designing and shipping vertical SaaS products for underserved markets in Brazil. End-to-end responsibility from product strategy and architecture to backend, frontend, DevOps, AI integrations and growth. Active product portfolio: - Chrema (chrema.app) — Multi-tenant SaaS managing the full debt collection and billing lifecycle for Brazilian SMBs and financial services. 5 .NET 8 microservices, MySQL, ActiveMQ event bus, native Boleto and PIX, dunning automation. 837 automated tests across the suite. - Pyrgos (pyrgos.app) — Multi-tenant SaaS for real-estate lead capture, combining tenant websites, CRM with kanban and round-robin routing, and a 24/7 AI assistant on WhatsApp (Twilio + Anthropic Claude) with per-turn lead scoring and sentiment analysis. - NETimobi — Real-estate SaaS focused on agency operations. Engineering scope I own personally across the stack: domain modeling (DDD, Clean Architecture), CQRS with MediatR, EF Core 8 migrations, ActiveMQ event-driven communication, Twilio Business API and Meta-approved template flows, multi-tenant data isolation, Kong Ingress, cert-manager, New Relic observability, GitLab CI per-service pipelines and Hangfire background workers. Frontends in Vue 3 + Vuetify (admin SPAs) and Nuxt 3 SSR (public tenant sites). Growth scope: Google Ads campaigns and conversion tracking, cold outreach automation (Postmark + SQLite pipelines), content programs across LinkedIn and Instagram, brand systems and landing pages in Astro 5. Bringing this end-to-end SaaS-building capacity to Fiverr — from greenfield product builds to fractional CTO engagements for technical and non-technical founders.

Software Engineer

Jan 2021 - Dec 2025 • 4 yrs 11 mos

Senior Software Engineer at IAUDIT Tecnologia, building and maintaining background check, appeals portal and whistleblower hotline platforms with 99.95% uptime and 250ms average response time. Key contributions: - Owned high-throughput data processing of large MongoDB collections fed by web crawlers, optimizing queries for up to 40% latency reduction. - Designed and maintained .NET microservices powering critical compliance and audit flows. - Full ownership across architecture, implementation, monitoring and production support — including incident response under tight SLAs. - Worked across the stack with .NET 6/7/8, EF Core, MongoDB and TypeScript front-ends.

Senior Software Engineer

Jan 2018 - Dec 2021 • 3 yrs 11 mos

Senior Full-Stack Engineer at Banco Digio across two engagements (2018-2019 and 2020-2021), spanning both team leadership and solo delivery. First tenure (2018-2019) — Technical lead of the Operations Portal team. Defined .NET Core + Vue.js architecture and engineering standards that drove a 40% reduction in production incidents and a 25% improvement in query response times. Partnered with infrastructure and security teams to sustain 99.9%+ system availability. Second tenure (2020-2021) — Sole architect and developer of Banco Digio's Open Data Portal, a regulatory disclosure platform integrated directly with the Central Bank of Brazil (BACEN). The technical proposal was selected through a competitive bidding process. Delivered on time and fully compliant with Open Finance standards, using .NET Core REST APIs and end-to-end ownership across architecture, security and production deployment.