Juan Fernando Lozoya Valdez

Full Stack Developer

Computer Systems Engineer experienced in building scalable web solutions (Angular, React & Node.js). Passionate about automation, performant UIs, and user-friendly tools.

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Profile

Computer Systems Engineer with 7+ years of experience delivering scalable web solutions for Silicon Valley companies. Specialized in fullstack JavaScript (Angular, Node.js), with a proven record of improving product performance, usability, and reliability. Experienced in leading distributed teams and driving innovation in test automation and user interaction technologies.

Experience

Functionize

Full Stack Developer · SEP 2019 - SEP 2025
  • Migrated legacy code from PHP/Smarty to a modern stack using Angular with TypeScript on the frontend and Node.js on the backend.
  • Developed and maintained core features of an AI-driven testing platform using Angular with TypeScript, enhancing state management through Redux to improve performance, scalability, and responsive design.
  • Collaborated with globally distributed teams to enhance UI/UX, improve frontend responsiveness, and align with product goals.
  • Maintained and optimized backend architecture using Node.js and Flask, refactoring legacy APIs, improving data handling efficiency, and implementing caching and monitoring solutions to enhance overall system performance.
  • Implemented seamless data delivery from AWS S3 and PostgreSQL databases for core platform features.
  • Built Architect, a powerful Chrome extension that automatically records user interactions across websites for test automation.
  • Dockerized and implemented Git Flow across multiple repositories to automate the delivery of key system components, significantly improving deployment speed and reliability.
  • Built and maintained RESTful APIs using Node.js, enabling full lifecycle external management (create, read, update, delete) of AWS Lambda functions.
  • Developed and integrated automated solutions for file management operations on AWS S3, and for managing Google Cloud Functions operations.
  • Administered and maintained development infrastructure on AWS EC2 and IAM.

Ventus Technology

Tech Lead · DEC 2018 - SEP 2019
  • Led a small team delivering a React Native application.
  • Owned solution design and served as the primary contact for technical decision-making across stakeholders.

Freelancer

Full Stack Developer · JUN 2018 - DEC 2018
  • Built tailored web portfolios and landing pages using frameworks like React and Django.
  • Implemented secure payment gateways and customized solutions to meet each client’s unique requirements.
  • Architected and maintained cloud-based infrastructures on AWS EC2 and Lightsail to support multiple projects.

CIMAV

Resident Engineer · JUN 2017 - DEC 2017
  • Developed a cross-platform, semi-multitenant application for conducting field sampling of environmental pollutants using React Native, TypeScript, and Django.

Education

2013 - 2017 · Computer Systems Engineering (mobile specialization)
ITD | Durango Institute of Technology — Bachelor of Engineering (B.E.)
GPA: 9.5 / 10.0

Projects

AI Test Platform UI

AI Test Platform UI

Functionize

Frontend for an AI-driven test automation platform, focusing on performance and large datasets.

ReactNext.jsReduxNode.jsTailwindPythonPHPDockerPerformanceAWSGCloud
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Architect

Architect

Functionize

Chrome extension that records user interactions (clicks, typing, drags, navigation, downloads, uploads, custom js injections, etc...) into a structured list for automation.

Chrome ExtensionJavaScriptReduxAutomationTailwind
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L-Ticket

L-Ticket

Personal Project

A marketplace app that connects event organizers with attendees. It provides a streamlined onboarding flow for organizers using Stripe, enables revenue splitting with platform commissions, and offers tools to manage event listings, ticket sales, and on-site ticket validation.

React NativeReactRESTful APIHybrid AppMongoDBNode.jsOnline PaymentsStripe
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Rave

Rave

Personal Project

This application is an evolving social network featuring integrated payment gateways, infinite scrolling, role-based user access, user analytics, and a dedicated blog page.

IonicMySQLRESTful APIHibridLaravelOAuth2Online Payments
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Insurance Wallet

Insurance Wallet

Ventus Technology

Built a reliable interface for distributing insurance policies, integrating SQL procedures with an API deployed on Azure’s server infrastructure.

SQLAzureMiddlewaresAPIsBackend
Field Sampling App

Field Sampling App

CIMAV

Cross-platform React Native app to record environmental pollutant samples and sync to server.

React NativeTypeScriptSQLiteRESTful APIMobile
Dockerized Chat

Dockerized Chat

Personal Project

This project is a CI/CD pipeline automation exercise for a React-based chat application and an Nginx reverse proxy. Both the client and server applications are automatically deployed and updated through the pipeline.

ReactSocket.ioNode.jsDockerCI/CD
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This Portfolio

This Portfolio

Personal Project

It is built with React, Next.js, and TypeScript, with a CI/CD pipeline for integration into AWS.

ReactNext.jsTypeScriptCI/CDAWS
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Notes App

Notes App

Personal Project

A modern, collaborative note-taking app built with React Native (Expo). Create, edit, and organize your notes in real time, instantly synced across devices. Includes secure authentication, offline access, and cloud backups for reliability and privacy.

ReactNext.jsTypeScriptCI/CDAWS
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