Curso de Introducción al Desarrollo Web: HTML y CSS (1/2)

Introducción a Laravel 5 - Primeros pasos con este framework

Learn Angular 5 from Scratch

Curso de FlexBox desde 0

CI/CD en Gitlab vía FTP: Despliegue automático de tu código

Mobile App Design: From Sketches to Interactive Prototypes

Curso de Introducción al Desarrollo Web (2/2)

Computer Science

Client: Multiple Clients in the United States

Technology Stack: HTML, JavaScript, CSS, Figma, GIT, React, Scrum Methodologies, Jira, GitHub, Design Systems, Okta Workflows Integrations, NextJS, WordPress, Python

Project Description
I developed a web application for a US-based company that offered end-to-end scholarship and grant management software, connecting sponsors with applicants. Throughout the project, I ensured that tasks were completed efficiently and tracked using JIRA.

To develop the application, I created high-quality, responsive components based on design wireframes, consuming API services to feed those components. I also ensured that the repository was clean and well-organized by creating branch-per-feature and reviewing team code.

To ensure that the application was of the highest quality, I analyzed use cases and developed a test-driven approach that allowed me to identify and address issues before they impacted the user experience.

Full Stack Engineer

Client: GTP

Technology Stack
HTML, PHP/Laravel, JavaScript, MYSQL, CSS, Photoshop, Illustrator, Figma, AdobeXD, WordPress, Ionic, Angular+2, GIT, SCSS, Docker, React, NodeJS, Python, PHP, UI / Web Design, Gitlab 

Project Description
I was responsible for the successful development of a GPS tracking system web application for a large vehicle fleet. This application, which has been used over 1,000,000 times and receives messages from more than 2000 vehicles every 15 seconds, was a critical tool for tracking the position and events of vehicles on the road.

In this project, I managed the back-end development of the application, as well as some server configuration and mail configuration using technologies such as PHP and NodeJS. I ensured that the application was scalable and could handle the large volume of data generated by the fleet.

In addition to my work on the GPS tracking system, I also created themes for WordPress from scratch. Using my design skills and expertise in web develo

Full Stack Developer

Client: Tigo Systems

Technology Stack: 
HTML, PHP, JavaScript, ORACLE, CSS, Photoshop, Illustrator

Project Description: 
As an Office Administrator at Tigo, a global telecommunications company specializing in internet, phone calls, and IT services, my role was crucial in ensuring the smooth and efficient operation of the office. Working in a fast-paced environment, I was responsible for a wide range of administrative tasks, including managing schedules, organizing meetings, and maintaining records.

In addition to my office duties, I also played a key role in maintaining Tigo's reputation for high-quality customer service. As part of this effort, I regularly visited clients to check their WiFi installations and ensure that they were receiving optimal service. Through these visits, I was able to establish strong relationships with clients and address any issues they may have had in a timely and effective manner.

Overall, my contributions as an Office Administrator at Tigo helped to e

Wireless Engineer

Client: Multiple Clients in the United States

Technology Stack: 
HTML, JavaScript, CSS, Figma, AngularJS, Angular+2, GIT, SCSS, Docker, React, Scrum Methodologies, Jira, GitHub, Design Systems, Python

Project Description:
I developed a web application for a US-based company that allowed clients to manage every aspect of their wedding planning, from guest lists to invitations. In this role, I was responsible for completing tasks tracked by JIRA and ensuring a clean repository by creating branch-per-feature and reviewing team code.

Using design wireframes as a guide, I created high-quality, responsive components for the application, consuming API services to feed those components. I also analyzed use cases to ensure a high-quality and effective solution, coding multiple projects within a single repository.

To ensure that the application was of the highest quality, I used a test-driven development approach, which allowed me to identify and address issues before they impacted the user 

Senior Software Engineer

OOma Web & Desktop Application is a cloud-based business phone service platform designed to streamline communication for business owners and their teams, providing continuity across devices. The solution includes features like virtual receptionists, voicemail-to-email, mobile and desktop apps, and call analytics.

Activities:

Led the development of new features across the React-based web and Electron desktop applications, ensuring responsive UI and seamless cross-platform functionality.

Diagnosed and resolved performance bottlenecks, improving overall application speed and reducing page load times through code-splitting, memoization, and lazy loading.

Collaborated closely with backend teams to integrate RESTful APIs, implementing features such as call logs, voicemail playback, and user preferences.

Mentored junior developers by conducting code reviews, pairing sessions, and knowledge-sharing workshops on modern frontend practices and tooling.

Implemented advanced state management 

Senior Frontend Developer

Client: Multiple Clients.

Technology Stack:
HTML, PHP, JavaScript, MYSQL, CSS, SCSS, Photoshop, Illustrator, WordPress, Ionic, Angular, Drupal, GIT, Scrum Methodologies, Gitlab, UI / Web / App Design 

Project Description:
As a collaborative team member, I played a key role in developing and maintaining a range of successful web applications and campaigns for major companies including Unilever, Miller Genuine Draft, and Tigo. My workflow was tracked using Gitlab, and I ensured that our repository remained clean and organized by creating a branch-per-feature.

In addition to my technical skills, I contributed to the team's success by bringing a positive attitude and a strong work ethic to every project. I was involved in all stages of the creative process, from conceptualization to execution, and I assisted with a variety of design projects. With my help, our team consistently met tight deadlines and delivered high-quality work.

My expertise extends beyond web development, and I have 

Design Manager

Client: Multiple Clients

Technology Stack
HTML, PHP, JavaScript, CSS, Photoshop, Illustrator, UI / Web Design, MySQL

Project Description
I played a critical role in the planning, development, testing, deployment, and maintenance of multiple web applications. I worked closely with the team members to ensure that every project was completed to the highest standards, from the initial design stage through to the final product.

One of my key responsibilities on these projects was handling much of the communication with clients. I worked closely with them to define the designer look and feel of each application, ensuring that it met their specific needs and requirements. This involved carefully listening to their feedback and incorporating their ideas into the development process.

Throughout the development process, I was dedicated to ensuring that each application was rigorously tested and that any issues were identified and resolved quickly. Once the applications were launched, I conti

Web Designer

Responsible for end-to-end development of custom web and mobile applications for clients in
the USA and Paraguay. Projects include an academic management system for Universidad del
Pacífico using React, Laravel, Node.js, and Tailwind CSS. Developed mobile apps with React
Native, integrated Firebase for push notifications, and implemented backend services with cron
jobs and a PHP-based UDP server for GPS hardware interaction. Managed continuous
integration/deployment with GitLab CI/CD and Agile project tracking with Jira.

Freelance

github

Know about Sergio Ballestero's work experience, education, bootcamps, certifications, and much more. Sergio Ballestero