Leonnardo Enes de Campos

Yolo Group – Software Engineer (Pay.io) & DevOps Engineer (Pay88 Team) Contributed to the development and operations of payment systems handling both fiat and cryptocurrency transactions. Worked on Pay.io, a platform enabling merchants to offer fiat-to-crypto payments worldwide in minutes, and Pay88, a core payments infrastructure. Key contributions: • Cryptocurrency Nodes: Implemented and maintained nodes for 10+ blockchains (Bitcoin, Ethereum, Polygon, Solana, Dogecoin, Ripple/XRP, Cardano, Tron, Base), ensuring reliable transaction processing. • Backend Development: Designed scalable, fault-tolerant payment systems using Elixir and Phoenix, focused on reliability, security, and performance. • Monorepo & CI/CD: Led migration to a monorepo with trunk-based development, building robust pipelines with GitHub Actions, CircleCI, AWS CodePipeline/Deploy, and automated preview environments via ArgoCD, Crossplane, and Kubernetes. • Cloud & Infrastructure: Managed AWS (IAM, EC2, EKS, RDS, DynamoDB, S3, CloudWatch, Secrets Manager, Lambda, Route53) and Hetzner Cloud resources. • Observability & Monitoring: Deployed and maintained Grafana, Prometheus, Alertmanager, Elastic Stack (Filebeat, Metricbeat, Logstash, Elasticsearch, Kibana) for metrics and logging. • Container & Orchestration: Extensive use of Helm, Kubernetes, Docker, Traefik, Nginx, Nomad/Consul for scalable workloads. Built reliable and highly available financial infrastructure, bridging fiat and crypto payments with global reach.

IAM, Integration and Middleware Squad Contributions: Image Vault Solution: Design and develop a robust middleware to centralize storage and retrieval of documents and images across all company products. Implemented watermarking to enhance data security and mitigate risks from leaks or hacker attacks. IAM Onboarding/Offboarding Automation: Automate user permission creation and removal, streamlining access management and improving security compliance. Key technologies & tools: • Containers & Orchestration: Helm, Kubernetes, Docker, Spinnaker, GCP Cloud Build • API & Gateway: Kong API Gateway with JWT authentication and OPA/OPAL authorization • Backend Microservices: Python (FastAPI, Flask) and Kotlin (Spring Boot, Gradle, OpenAPI, unit tests with MockK, GCP Pub/Sub, Redis, Flyway, logging) • Cloud & Infrastructure: GCP resources including IAM, API Services, Kubernetes Engine, Cloud Functions, Postgres, Memory Store, Cloud Build, Logging, Pub/Sub • Identity & Middleware: Keycloak for user federation, middleware API, and custom plugins (including face biometric authentication flow) • Observability & Monitoring: New Relic, Splunk • Testing & Performance: JMeter for load testing and functional performance measurement • Integrations: Microsoft AD and Google Workspace via GCDS Built secure, scalable, and automated solutions supporting enterprise-wide identity, middleware, and document workflows.

NYU – New York University Infrastructure Maintenance & Full Stack/DevOps Development Contributions: • Maintain and improve a secure, hybrid cloud environment for government agencies to share and access confidential information. • Redesign & Migration: Lead redesign and migration of solution architecture to AWS Outposts, enhancing security, scalability, and usability. • Isolated Environments: Provide isolated virtual environments preserving security and privacy, offering each user a preconfigured data science environment. • Containerization: Automate environment provisioning using Docker containers for each user session, ensuring consistency and isolation. • Support DevOps and Full Stack development to ensure the platform is reliable, secure, and scalable for federal, state, and local agencies. Key technologies & tools: AWS Outposts, Hybrid Cloud, Docker, Virtual Machines, Data Science Environments, DevOps Practices, Full Stack Development Built a robust, secure platform enabling government agencies to work with sensitive data safely and efficiently.

Selected Projects – Various Sectors Food Sector • Develop a solution to monitor product expiration dates on store shelves, optimize tracking, and reduce labor costs. Healthcare Segment (Home Care) • Implement a control system for the entire home care process, from patient intake to prescription management, financial rules, treatment tracking, and medical discharge. Alternative Investment Management Client • Build a control and management system for judicial credit recovery, streamlining case tracking and recovery processes.

Selected Projects – Various Clients IPIRANGA – Transportation Sector • Develop a solution to build customer loyalty at filling/service stations, allowing users to earn points redeemable for multiple consumer benefits. IES – Sports Sector • Collaborate on product development with a startup to monitor athlete performance (soccer, futsal, and society) across technical, physical, behavioral, and tactical criteria via mobile devices, reducing distance between students, guardians, and technicians.

Selected Projects – Various Clients GLOBO TV • Lead the financial approval flow control system and resource/team reporting for TV Globo production. ANBIMA / CVM • Lead the SRE system developed for CVM (Securities Commission) via partnership with ANBIMA, enabling dynamic workflows for evaluating securities-related applications from document analysis to final approval. IPIRANGA – Transportation Sector • Lead a strategic project for fleet management, designing optimal routes for light and heavy vehicles, enhancing payment security and reducing fraud typical in the sector.

• Develop and maintain TV Globo documentation system to catalog programs and enable fast video search.

• Produce and maintain a system connecting all education sectors in Rio de Janeiro. • Develop integration systems with DETRAN and Rio Card. • Create a web framework using NHibernate, Fluent Pattern, Dependency Injection, AutoMapper, NHValidation, with multi-file configuration, serialization, virtualization, and unit tests with StoryQ.

• Develop own product “Invoice Electronic System” (service and product) using MVP architecture and design patterns including Abstract Factory, Builder, Visitor, Strategy, and Observer.

• Develop a regulatory covenant system (SICONV) for the Brazilian Federal Government using MDA methodology from UFRJ.

• First experience developing enterprise back-office systems using C#.NET and Windows Forms.