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Mario Alberto Valles

@marioalbertovalles

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Full Stack Developer with 7+ years building production web apps, APIs, dashboards, and cloud platforms.

United States

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What I'm looking for

I’m looking to build scalable full-stack products end-to-end—React/Node, REST/GraphQL, data modeling, and cloud deployments—while partnering cross-functionally in Agile teams to improve performance, reliability, and developer experience.

I’m a Full Stack Developer with 7+ years building production web applications, APIs, dashboards, internal tools, and database-backed platforms. I focus on strong system design—REST API and GraphQL design, authentication/authorization, microservices, event-driven architecture—and reliable delivery through testing and CI/CD.

In my recent role as a Senior Full Stack Developer, I built scalable full-stack web applications using React, Next.js, Node.js, REST APIs, and GraphQL for internal product workflows and business dashboards. I improved page load performance by about 30% and reduced frontend errors by 35% through better rendering, API handling, database query optimization, and deployment practices across AWS, Azure, and GCP with Docker, Kubernetes, GitHub Actions, Jenkins, and Terraform.

I’ve also delivered high-quality frontend solutions in Angular, improving production support response and accessibility-aware UI while strengthening unit testing and code review quality. I collaborate across UI/UX, product, backend, and DevOps teams in Agile/Scrum, and I mentor developers to raise maintainability, consistency, and team velocity.

Experience

Work history, roles, and key accomplishments

Senior Full Stack Developer

Walmart, Inc.

Jul 2023 - Mar 2026 (2 years 8 months)

Built scalable full-stack web applications using React, Next.js, Node.js, REST APIs, and GraphQL, supporting internal workflows and business dashboards. Improved page load performance by ~30% and helped strengthen reliability through backend authentication/authorization and API integration work.

React Next.js REST APIs GraphQL Authentication Microservices Docker Kubernetes CI CD

Mid-Level Frontend Developer

Web Guru's LLC

Feb 2021 - Apr 2023 (2 years 2 months)

Developed Angular-based, reusable UI components and responsive layouts for production web platforms. Reduced application errors by ~35% through JavaScript/UI debugging, improved unit testing, and higher-quality code reviews.

Angular TypeScript JavaScript Responsive UI Unit Testing Debugging Accessibility Agile Scrum Browser compatibility

Junior Full Stack Developer

Mashup Garage

Jul 2015 - Oct 2020 (5 years 3 months)

Contributed to full-stack web application development across frontend, backend services, API integrations, and database-backed workflows. Reduced frontend issue rates by ~25% through bug fixes, improved JavaScript/CSS structure, and better implementation quality in code reviews.

JavaScript HTML CSS API Integration Backend Services Database Backed Apps Performance Optimization Responsive UI Code Review Agile Scrum

Frontend Developer

iScale Solutions

Jan 2015 - Jun 2015 (5 months)

Developed and maintained frontend components using HTML, CSS, and JavaScript to improve usability and UI consistency. Implemented features and bug fixes, including third-party API connections, and supported browser debugging and code review follow-through.

HTML CSS JavaScript Debugging Code Review Frontend Agile Collaboration