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
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
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
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
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.
- Java (8–21)
- Spring Boot
- REST APIs
- PostgreSQL
- Oracle
- AWS basics (Lambda/Cognito)
- Git/GitHub
- Testing (JUnit/MockMvc)