// software developer · paraguay
Marcelo González, software developer
Computer engineer. I design and build custom software from warani.dev
5+ years taking platforms end to end — from the first commit to the production deploy.
// about me
Fullstack developer, from the database to the deploy
I'm Marcelo González, a computer engineer and software developer based in San Lorenzo, Paraguay. For over 5 years I've been building software that runs in production.
I've worked on platforms connecting financial institutions to the Central Bank of Paraguay's instant payment system, and also on management systems, internal dashboards and third-party integrations. I cover the full cycle: backend, frontend, database and deployment.
- Location
- San Lorenzo, Paraguay
- Role
- Fullstack Developer
- Languages
- Native Spanish · English A2-B1
- Availability
- Open to projects
// track record
Where I've been and what I built
Company names are withheld under confidentiality agreements. The work itself is described exactly as it happened.
Sep 2023 — Present
Senior Fullstack Developer
Fintech · Payment systems · Asunción
- Implemented in Java and Spring the mandatory operational flows for SPI participants set out in Circular SGGOF No. 008/2025 of the Central Bank of Paraguay, rolled out gradually per institution behind feature flags.View the BCP circular
- Led the adoption of the PY-QR standard from Circular SGGOF No. 008/2024, regulated this year, building the multi-network QR payment hub in Java and Spring integrated with the instant payment system.View the BCP circular
- Contributed to an electronic invoicing system in Python and FastAPI that automates issuing, voiding and querying electronic documents, with workers, connection pooling, RabbitMQ queues and APM monitoring.
- Rebuilt the admin panel from scratch with React, TypeScript and Zustand: members, transactions, reconciliations and reports, with granular permissions and advanced filtering.
- Contributed to a lending platform built with Python, FastAPI and React on Kubernetes, with Redis caching, dockerised services and CI/CD pipelines in Jenkins.
Dec 2022 — Sep 2023
Fullstack Developer
Enterprise software · Asunción
- Built features and improvements across enterprise applications in Java and Spring Boot, covering both business logic and web interfaces.
- Led the resolution of critical production incidents and coordinated the technical onboarding of new clients onto the platform, with no service interruption.
- Administered and configured Linux environments for integration testing and deployments, keeping development and staging stable.
Aug 2021 — Dec 2022
Developer
Higher education · San Lorenzo
- Built and maintained REST services with Java and Spring Boot, refactoring existing modules to improve maintainability and endpoint performance.
- Optimised queries and data structures in PostgreSQL, cutting response times on the platform's most frequent operations.
// services
How I can help
I work end to end. If you only need one piece, that works too.
Web development
Custom websites and web applications: fast, accessible and built to rank in search engines.
Systems development
Internal platforms, back-office tools and management systems that carry a business's daily operation.
APIs & backend
REST services, workers, message queues and an architecture that holds up when volume grows.
Integrations & payments
Payment methods, interbank transfers, electronic invoicing and third-party services.
Databases & performance
Modelling, query optimisation and caching strategies so the application stops dragging.
Deployment & DevOps
Docker, Kubernetes and CI/CD pipelines so shipping a release is routine, not an event.
// stack
Tools, not religions
I pick each piece for the problem, not for the trend.