Greivin Arce — Backend Software Engineer

Backend Engineer focused on secure, scalable systems.

I design and deliver production-grade APIs using Java and Spring Boot, with an emphasis on security, reliability, and maintainable architecture. I’m comfortable working end-to-end: requirements → design → implementation → automated testing → deployment.

Architecture & quality

Clean architecture, consistent response contracts, validation standards, pagination/sorting patterns, and testable service boundaries.

Security mindset

OAuth2/JWT flows, role/group-based access, safe input handling, and API hardening aligned with real-world usage.

Data & integrations

Strong SQL + domain modeling, working with PostgreSQL and Oracle, and integrating with external services in regulated workflows.

Projects

Selected work that highlights API design, reliability, security, and real-world integrations.

Personal project

Transaction Processing API

Secure REST API with pagination, sorting, and integration tests, designed with clean architecture and production reliability in mind.

Focus

  • API design & consistency
  • Pagination and sorting standards
  • Integration testing
  • Validation & error contracts
  • Java
  • Spring Boot
  • PostgreSQL
  • JUnit
GitHub →

Client project

Electronic Invoicing Platform — Municipalidad de Heredia

End-to-end electronic invoicing system built from scratch, fully compliant with Costa Rica’s Hacienda v4.4 requirements.

Focus

  • Government-grade compliance
  • REST API integrations
  • Regulated financial workflows
  • Angular + backend coordination
  • Java
  • REST APIs
  • Angular
  • Hacienda FE v4.4

Private repository (client-owned).

Client project

Farm Management System — Universidad Nacional de Costa Rica

Backend refactor and cloud migration of a legacy JavaFX system to Java 21 and REST APIs, preserving the existing UI.

Focus

  • Large-scale refactor
  • JavaFX → API-based architecture
  • AWS Cognito authentication
  • Cloud deployment
  • Java 21
  • REST APIs
  • AWS Cognito
  • Cloud

Private repository (institution-owned).

Client project

Electronic Invoicing System — AyA (≈45,000 invoices/day)

Migration and maintenance of a high-volume electronic invoicing platform processing approximately 45,000 invoices per day.

Focus

  • High-throughput systems
  • Oracle-based large datasets
  • Regulatory migrations (v4.3 → v4.4)
  • Production-critical stability
  • Java EE
  • Oracle
  • PrimeFaces
  • Payara
  • Hacienda FE v4.4

Private repository (client-owned).

Experience

GBSYS — Software Engineer

2024–Present

  • Modernized legacy modules to a consistent Spring Boot architecture.
  • Built secure endpoints with validation, structured responses, and automated tests.
  • Worked with Oracle/PostgreSQL and electronic invoicing workflows.

Skills

Core tools I use regularly. Projects provide deeper context and real-world application.

Contact

If you want to collaborate or discuss opportunities, feel free to reach out.

[email protected]