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// software developer · paraguay

Marcelo González, software developer

Computer engineer. I design and build web applications, APIs and custom systems.

5+ years taking platforms end to end — from the first commit to the production deploy.

Get in touchSee experienceWhatsApp

// about me

Fullstack developer, from the database to the deploy

Marcelo González, software developer

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.

  1. 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.

  2. Dec 2022 — Sep 2023

    Full Stack 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.

  3. 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.

01

Web development

Custom websites and web applications: fast, accessible and built to rank in search engines.

02

Systems development

Internal platforms, back-office tools and management systems that carry a business's daily operation.

03

APIs & backend

REST services, workers, message queues and an architecture that holds up when volume grows.

04

Integrations & payments

Payment methods, interbank transfers, electronic invoicing and third-party services.

05

Databases & performance

Modelling, query optimisation and caching strategies so the application stops dragging.

06

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.

Backend

JavaSpring BootPythonFastAPINode.jsExpressGoC#.NET

Frontend

ReactTypeScriptZustandAstroTailwind CSSJavaScript

Data

PostgreSQLOracleRedisMongoDBRabbitMQ

Infrastructure

DockerKubernetesAWSCloudflareAzureJenkinsGitLinux

Observability

GrafanaPrometheusElastic Stack

// how i work

Four steps, no mystery

Direct communication, written scope and progress you can actually see.

1

step · 01

I understand the problem

Before proposing any technology, I ask what has to happen in the business for this to count as a success. I map constraints, deadlines and what already exists. Sometimes the conclusion is that nothing needs to be built.

2

step · 02

We agree on scope

You get it in writing: what's in, what's out, how long it takes and the assumptions behind it. If something can't be estimated yet, I say so instead of inventing a date.

3

step · 03

I build in pieces

Partial deliveries you can open and try, not status reports. Versioned, reviewed code deployed to an environment you have access to from day one.

4

step · 04

I hand off and stay around

Documentation of how it works and how it deploys, so any team can pick it up. After wrap-up I'm still around for questions and adjustments.

// education

Academic background

2019 — February 2026

Computer Engineering

Universidad Columbia· Asunción

Full undergraduate degree, with a thesis defended in February 2026: a system implementing Mirai for the early detection of breast cancer.

Certifications

// faq

What people usually ask me

If your question isn't here, write to me below.

Got something in mind?

Tell me what you need and I'll say frankly whether I can help, how long it would take and what it would involve.

Write to me

// let's talk

Tell me what you're building

I reply within 24 business hours.

Location

San Lorenzo, Paraguay

Social

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