Rodrigo Santos

Backend Engineer

TOTVS

Feb 2022 - Present • 4 yrs 9 mos

I work in a 10-person product squad on Linx OMS, an omnichannel platform used by large retailers. I am the primary technical reference in the squad for the Freight Quotation and Freight Quotation Configuration APIs, which provide delivery options during checkout based on carrier contracts, ZIP ranges, package data, and configurable freight rules. - Led the technical investigation for a new customer requirement of freight quotation responses under 400 ms. Used CPU profiling, load tests, and Grafana data to identify bottlenecks and propose the modernization path. Linx later reported 64.7% lower average response time and 76.3% lower P99 after the 2025 Freight Quotation Engine refactor. - Proposed splitting configuration writes from the read-heavy quotation path, then designed the initial Configuration API structure and implemented about half of the migrated endpoints. Preserved existing API contracts and gradually rerouted validated endpoints through AKS ingress as the new service was rolled out. - Argued for improving the existing Node.js service instead of rewriting it in Go, based on profiling results, team experience, delivery risk, domain complexity, and the customer deadline. The team kept Node.js, separated the workloads, moved from Restify to Express, and continued optimizing the service incrementally. - Modernized the freight services by replacing legacy dependencies, improving behavior-focused tests, upgrading MySQL from 5.7 to 8.4 across the application and Azure database, and resolving the remaining 255 SonarQube findings in the Freight Quotation repository. - Participate directly in production work through PR reviews, critical incident response, AKS/FluxCD deployments, rollback planning, database migrations, and Grafana/Prometheus monitoring. I also help onboard newer engineers and contribute to Inventory, Packages, Freight Cost (Go), and Catalog (Go) services.

Backend Engineer

Screen

Nov 2020 - Feb 2022 • 1 yr 3 mos

Worked on a corporate communications platform (Screencorp) with corporate TV, CMS, and internal employee communication features. While another backend group focused on rebuilding the platform in Laravel, I was mainly responsible for keeping the Yii production API stable while continuing to ship fixes and features. - Owned the Trello/Kanban workload for the production backend, reproducing issues from bug reports, tracing root causes, shipping fixes and features, and coordinating validation with QA, frontend, and mobile developers. - Built the Node.js push-notification microservice after the PHP implementation developed delivery problems, integrating queued processing with Firebase and improving notification stability and maintainability.

Full Stack Developer

Fiat

Sep 2019 - May 2020 • 8 mos

Served as the sole developer in the Brazilian FIAT of the State of Piauí (Jelta Veículos) IT department, maintaining and expanding an internal BI/reporting system used by managers across dealership sales and service operations. - Worked directly with managers to turn reporting requests into ETL flows and dashboards. Traced data in sales, service, and financial systems, transformed it from SQL Server into a MySQL reporting database, and built dashboards with filters, charts, and operational views. - Maintained the application end-to-end, including deployments, backups, support, scheduled data processing, and SQL performance work. Managers reported being able to identify and address operational issues faster with the dashboards.