Manuel Alfaro

Software Engineer • Dublin, Ireland

About me

Backend Software Engineer with 7+ years of experience building scalable, production-grade systems in fintech and payments, with a growing focus on data engineering and applied AI.

Experienced in leading backend architecture for payment processing platforms, designing distributed resource coordination systems, async processing pipelines that reduced endpoint latency by up to 90%, and transactional data lakes for analytics at scale. More recently focused on building internal AI assistants using Model Context Protocol (MCP) with natural language-to-SQL and agentic RAG capabilities, enforcing least-privilege data access patterns across integrated sources.

Skills

Backend Development

Data Management

Version Control

AI Engineering

Cloud Computing

System Design

Data Analysis

Experience

Backend Engineer at CuboPagoLa Libertad, El Salvador · Jul 2021 – Present

Led the backend architecture of a payment processing platform from the ground up, scaling it to over 2M transactions per year across El Salvador, Guatemala, and Panama with 79% year-over-year growth, by designing the initial system architecture, database schema, and engineering workflows as Head Backend Engineer.
Eliminated 100% of concurrent transaction overlap errors across distributed terminals by designing and implementing a Redis semaphore-based rotation system, managing up to 4 simultaneous transactions per terminal.
Reduced endpoint latency by 70–90% by offloading heavy processing to asynchronous background workers and decoupling user notifications via async email delivery.
Architected a data warehouse pipeline on BigQuery using Airbyte for ingestion (~2K records/hour) and Terraform-managed Lambda schedulers to produce raw Parquet files, enabling scalable transaction analytics from day one.
Autonomously identified and resolved recurring reporting interruptions by designing and deploying an internal AI assistant via Model Context Protocol (MCP) with natural language-to-SQL capabilities over BigQuery, enabling management to self-serve operational queries.
Led API certification processes and cross-border conflict resolution with payment processors across El Salvador, Guatemala, and Panama, delivering reliable payment integrations across multiple markets.
Collaborated with Operations and Management teams through iterative design sessions to build internal tooling, including deposit-to-transaction reconciliation and automated reporting workflows, reducing manual workload by ~40% and eliminating 3 recurring manual reports.
Diagnosed a peak-traffic degradation on the transaction history endpoint by profiling query execution time and call frequency during high-load windows, resolving the issue through query optimization and indexing without requiring an RDS instance upgrade.

Software Engineer at Applaudo StudiosSan Salvador, El Salvador · Sep 2019 – Jul 2021

Designed and built a candidate screening API that automated applicant filtering via randomized technical assessments using JWT tokens, reducing manual recruiter effort.
Led backend development of an internal employee visibility platform for ~200 employees, building skill-based developer ranking endpoints used by management for staffing decisions.
Contributed to the migration of 5 Node.js/NoSQL microservices on GCP to a NestJS/PostgreSQL monolith, reverse-engineering and documenting service flows to ensure system alignment.
Implemented a Redis caching layer for third-party property valuation API calls, reducing external requests by ~70% and lowering infrastructure costs.

Education

Msc. Big Data Management & Analytics at Griffith College

Dublin, Ireland · Sep 2025 - Sep 2026

Master in Cloud Computing at Immune Institute

Madrid, Spain · Feb 2024 - Mar 2025

Bachelor of Science in Computer Science at Don Bosco University

San Salvador, El Salvador · Jan 2014 - Nov 2019

Tools

NodeJS

Ruby

Python

Java

PostgreSQL

Spark

AWS

Contact

malfaro@devman.cc

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