Data Engineering
Pipelines, reconciliation, PostgreSQL models, data-quality checks and operational reporting.
Building better systems
Vinicius
Santana
Software & Data Engineer
I build reliable systems where software, data and infrastructure meet.
- Data Systems
- Distributed Infrastructure
- Backend Engineering
- Public Health
Brazil, UTC-3 · Software, data & operations
Three systems. A conceptual map of the work, not a live network.
Resume & contact
A quick path to the practical details.
I’m open to remote Software Engineering, Data Engineering and platform-focused conversations.
About
I build backend systems for data-heavy, operational work.
I’m Vinicius Santana, a Python backend engineer in Brazil. I build FastAPI and PostgreSQL services, validation workflows and automation for municipal public-health operations—work that validates 21,000+ records each month and reduced a municipality-wide reconciliation cycle from 240+ person-hours to about four.
Software Engineering
Backend APIs, automation tooling, testable workflows and maintainable service boundaries.
Experience
Software, data, infrastructure and operations in practice.
Software Engineer experienced in building Python/FastAPI services, maintaining Java/Spring systems, debugging production failures, measuring performance, and operating reliable PostgreSQL-backed platforms. Built validation, integration, and automation workflows for municipal healthcare, processing 21,000+ monthly records, reducing a 240+ person-hour reconciliation cycle to about 4 hours, and sustaining claim rejection rates below 1% for 8 consecutive cycles.
Prefeitura de Presidente Epitácio
Software Engineering & Health Data Systems
Oct 2023 — Present
- Built Python/FastAPI validation services and maintained Java/Spring/PostgreSQL systems, modeling longitudinal patient identity across historical names, missing or changed CPF identifiers, and CNS changes for 21,000+ monthly records.
- Diagnosed Java/Spring performance degradation caused by an unset optional identifier that prolonged object lifetime and increased garbage-collection pressure; fixed identifier assignment and cleanup behavior to restore stable execution.
- Built performance instrumentation to detect N+1 patterns, repeated execution paths, and latency regressions, validating changes through baseline/diff comparisons, shadow runs, and night/chaos tests.
- Debugged an edge agent across installation, discovery, and execution using isolated VMs, MITM traffic inspection, and runtime diagnostics; traced repeat-install failures to stale Windows Registry and machine state, then updated uninstall cleanup and forced discovery during installation.
- Reduced healthcare claim rejection rates from 12%+ to below 1% across 8 consecutive billing cycles by engineering 11 auditable Python/SQL validation and reconciliation rules across legacy and government systems.
- Cut municipality-wide workforce reconciliation from 240+ person-hours to about 4 per cycle by building Python extraction, Parquet processing, provenance controls, and centralized APIs.
- Built an S3/Parquet analytical path cataloged by AWS Glue and queried through Athena, and worked on SQS, Lambda, and SES workflows for cross-application audit events and transactional email.
- Authored installation, operations, troubleshooting, and handoff guides, and trained 5 staff members plus 3+ physicians and nurses on production workflows, auditing, and issue resolution.
IT Infrastructure & Systems Support · Internship
Nov 2021 — Oct 2023
- Designed and shipped a domain-specific plugin that reduced a mandatory dengue-reporting workflow from 7 manual steps to one checkbox.
- Operated health-check-driven failover for Nginx and application replicas across distributed municipal nodes, shifting traffic from unhealthy nodes within approximately 1–3 minutes with no reported user-visible outages.
- Improved release and recovery reliability with Ansible/Jenkins automation, health checks, backup checkpoints, certificate and credential rotation, and rollback procedures; restored a 9 GB PostgreSQL-backed application within 1 hour after a failed update.
Irmãos Santana
Business Analyst & Operations Manager
Feb 2021 — Jan 2026 · Part-time
- Increased profitability by 26% and reduced feed waste by 11% for a 20-ton/month aquaculture operation by redesigning pricing, purchasing, inventory, cost-control, and production workflows.
- Built Python decision-support tools, spreadsheet and ERP automations, and MQTT telemetry prototypes to measure production KPIs, inventory, water quality, and operating costs.
Stack
Tools used across backend, data, reliability and frontend work.
Backend
- Python
- Java
- FastAPI
- Spring
- Pydantic
- SQLAlchemy
- REST/OpenAPI
Data
- SQL
- PostgreSQL
- Redis
- DynamoDB
- InfluxDB
- Parquet
- MinIO/S3
Testing & Quality
- Pytest
- Hypothesis
- Testcontainers
- Ruff
- Pyright
Platform & Reliability
- AWS
- Docker
- Linux
- Ansible
- Prometheus
- Grafana
Frontend
- TypeScript
- React