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WALTER CASTILLO — SAN SALVADOR

Software architect & UX engineer

Senior Software Engineer and UX Development Lead based in San Salvador, El Salvador. I design and implement scalable systems for eCommerce platforms, with over 6 years of experience across system integration, UX engineering, and international trade.

Contact meSee my experienceSee my projects

+6 years of experience

5 countries with deployed systems

Currently

  • Senior Web Developer at Almacenes SIMAN
  • Leading UX and web development for regional eCommerce (React, Node.js, VTEX)
  • Deepening DevOps and cloud skills through hands-on homelab work
PostgreSQLTypeScriptReactNode.jsDockerVTEXDesign systems

An engineer who aligns technology with business strategy.

As a Senior Software Engineer and UX Development Lead, I design and implement scalable systems for eCommerce platforms. With over 6 years of experience across system integration, UX engineering, and international trade, I align technology with business strategy to deliver measurable impact.

I currently lead UX and Web Development at Almacenes SIMAN, building multi-country eCommerce ecosystems across Central America, driving performance, usability, and scalability through modular frontend architectures, design systems, and API integrations.

Previously, I contributed to international cooperation and trade programs across Central America, developing digital platforms and cross-border operations. I hold a Master’s in Software Architecture, which deepens my expertise in enterprise system design, cloud-native solutions, and scalable software ecosystems that bridge technology, design, and business.

UX-led deliveryIntegration-first architectureBusiness-aligned technologyPragmatic systems
Portrait of Walter CastilloWalter Castillo

Where I have worked and what I have built.

Senior Web DeveloperAug 2024 — Present
Almacenes SIMAN — San Salvador, El Salvador

Lead front-end and UX development for SIMAN’s regional eCommerce platforms across Central America, ensuring consistent, high-quality user experiences.

  • Develop and maintain React-based, modular front-end components integrated with a headless CMS and eCommerce APIs (VTEX).
  • Implement and manage design systems to maintain cohesive brand identity and accessibility standards.
  • Optimize site performance, SEO, and analytics tracking for improved engagement and conversion rates.
  • Collaborate with multidisciplinary teams (design, marketing, CMS, and IT) to align business and technical goals.
ReactHeadless CMSVTEXDesign systemsSEO
Systems Design ConsultantFeb 2025 — Jul 2025
IESC — Improving Economies for Stronger Communities (ATraCSI Project)

Supported the design of electronic payment and integration systems for El Salvador’s Foreign Trade Facilitation Platform (SFCE).

  • Designed the API-based service architecture (Angular, Java Spring Boot) to automate import processes for the Ministry of Agriculture (MAG).
System designAPI designPaymentsArchitecture
Software Developer Analyst SupervisorNov 2020 — Aug 2024
Nathan Associates — USAID Regional Trade Facilitation Project

Led full-stack and architectural design for regional trade and customs systems across El Salvador, Guatemala, and Honduras.

  • Managed a cross-border development team building BPM and integration systems to optimize trade processes.
  • Designed and implemented modular, API-driven platforms using Angular, Laravel, C# (ASP.NET), React, Django, and PostgreSQL.
  • Coordinated directly with government tech teams, ensuring seamless adoption of new systems.
ReactDjangoLaravelC#AngularJSPostgreSQLBPMArchitecture

A look at the range of the work.

Product & UX

UX leadership · React · VTEX

Regional eCommerce UX

Redesigned purchase journeys for a platform operating across multiple Central American countries, simplifying interactions that used to cause friction and leaving a component base the team could reuse across markets.

ReactHeadless CMSVTEXDesign systems
Read case study →
Architecture & Scale

Architecture · BPM · Cross-border team

Regional trade & customs systems

Designed modular BPM platforms for trade processes across El Salvador, Guatemala, and Honduras, leading a cross-border team and coordinating with government technology teams in all three countries.

ReactDjangoPostgreSQLBPM
Read case study →
See more projects

Full-stack, UX, and infrastructure.

Frontend

ReactTypeScriptJavaScript (ES6+)HTML5CSS3GraphQLAngularJS

Backend

Node.jsPythonPHPJava

DevOps

GitDockerCI/CDNginxTerraformGoogle Cloud Platform

UX & design

FigmaAdobe XDDesign systemsAccessibilityPrototyping

Databases

PostgreSQLMySQLPostGIS

Other

API designSystem integrationAgile methodologies

Master's in Software Architecture

2023 — 2026

Universidad Don Bosco

Information Systems Engineer

2014 — 2018

Universidad de El Salvador

Google UX Design Professional Certificate

2022 — 2023

Coursera

Spanish

Native

English

Advanced

French

Basic

Open to new opportunities and collaborations.

(+503) 7728 8985

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