César Augusto Méndez Vargas, Developer in Santiago De Los Caballeros, Santiago Province, Dominican Republic
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César Augusto Méndez Vargas

Verified Expert  in Engineering

Software Developer

Santiago De Los Caballeros, Santiago Province, Dominican Republic

Toptal member since April 8, 2019

Bio

César is a systems engineer with in-depth and far-ranging experience managing and creating projects from the very beginning. He particularly loves the research and collaboration aspects of projects. Technically, what César cares about the most is the performance, database structure, algorithms, and simplicity of the system as a whole. He's curious, collaborative, holistic, and a team player.

Portfolio

Freelance Work
Jenkins, Pusher, PHP, jQuery, PhalconPHP, Laravel, WordPress, JavaScript, MySQL...
Scoopt, Inc t/a InPress
PHP, Laravel, Amazon Web Services (AWS), React Native, Python, TypeScript...
Virtual Guest Services, LLC
PHP, HTML, Mobile Development, CodeIgniter, MVC Frameworks, HTML5, Full-stack...

Experience

  • MySQL - 7 years
  • PHP - 6 years
  • JavaScript - 6 years
  • WordPress - 5 years
  • Unit Testing - 4 years
  • Amazon Web Services (AWS) - 3 years
  • Laravel - 3 years
  • Go - 1 year

Availability

Part-time

Preferred Environment

Visual Studio Code (VS Code), CentOS, Windows 10

The most amazing...

...thing I’ve done was reduce the time for a crucial process on a fantasy sports app from several minutes to only two seconds on average.

Work Experience

Systems Engineer

2013 - PRESENT
Freelance Work
  • Built an online grade reporting tool for a public school.
  • Developed a makeup artists' video tutorial platform based on WordPress and Vue.js with features such as channels, likes, and products (specifically those listed on the platform's makeup videos).
  • Performed several software features implementation analyses for companies in terms of viability and the best approach for implementation.
  • Automated the booking system for a small hotel in Brazil.
  • Created a system for a company that rented audiovisuals to universities to manage device availability, have a list where all the devices where rented, easily see who was responsible for each rental, and manage the daily operation of incomes and expenses.
Technologies: Jenkins, Pusher, PHP, jQuery, PhalconPHP, Laravel, WordPress, JavaScript, MySQL, APIs, Linux, Apache, Bootstrap, MVC Frameworks, HTML5, Full-stack, Python, React, AI-enabled Applications, Vanilla JS, Programming, eCommerce, Full-stack Development, Shopify, Shopify API, FastAPI, Unit Testing, REST APIs

Back-end PHP and Laravel Developer

2024 - 2025
Scoopt, Inc t/a InPress
  • Refactored API responses using standardized Laravel resources for consistency, faster development, and improved response handling.
  • Moved user images from the back-end server to S3 for faster delivery and reduced server load. Integrated with CloudFront to serve images closer to users, improving performance and scalability across regions.
  • Collaborated closely with the team, including mobile developers and designers, to ensure seamless integration of key functionalities.
Technologies: PHP, Laravel, Amazon Web Services (AWS), React Native, Python, TypeScript, MySQL, Twilio API, Programming, Optimization, Full-stack Development, Unit Testing, REST APIs

Back-end Mobile Developer

2024 - 2024
Virtual Guest Services, LLC
  • Created a Swagger documentation for the API, which was intended to be used by iOS and Android developers.
  • Fixed several bugs, allowing access from several browsers, and secured the website with a proper SSL configuration.
  • Re-added lost functionality by using several versions of the project, then used Git for version control and GitHub as the online repository to prevent this issue from happening again.
Technologies: PHP, HTML, Mobile Development, CodeIgniter, MVC Frameworks, HTML5, Full-stack, Vanilla JS, Programming, Full-stack Development, REST APIs

Lead Software Engineer (via Toptal)

2019 - 2024
SellHound
  • Led a team of five developers with different stacks: AI, mobile, and full stack.
  • Reduced the loading time of the main platform component from an average of 15 seconds to just 1.5 seconds.
  • Created a business intelligence ecosystem allowing company directors to access unprecedented reports and key metrics.
Technologies: Laravel, Amazon Web Services (AWS), Redis, Chrome Plugins, Microsoft Power BI, HTML, JavaScript, Git, Node.js, Chrome Extensions, APIs, Linux, Bootstrap, MVC Frameworks, HTML5, Full-stack, React, Technical Leadership, OAuth, React Native, AI-enabled Applications, Vanilla JS, Programming, Optimization, Full-stack Development, PostgreSQL, Unit Testing, REST APIs

Senior Software Engineer

2022 - 2023
Hearst
  • Created a video platform by integrating several in-house microservices, AWS services, and 3rd-party APIs.
  • Fixed a slow query from 50% CPU utilization and six seconds execution time to drop CPU usage to less than 0.5% and execute in milliseconds.
  • Resolved a component that became non-functional due to its core database table being over 60 million records.
  • Exported 1,000,000 users from production to a marketing service without compromising performance.
  • Collaborated with several teams, including Product, Legal, visual designers, and front-end engineers, to shape, develop, and deploy core features.
Technologies: JavaScript, PHP, WordPress, Python, Amazon S3 (AWS S3), Amazon Simple Notification Service (SNS), Amazon Simple Queue Service (SQS), WordPress VIP, Apple News API, Unit Testing, REST APIs

Systems Engineer

2015 - 2021
Nexo Global
  • Supervised a small team of developers, helping them to deliver high-quality and useful features.
  • Automated code deployments to staging and production.
  • Created the guidelines for development and communication.
  • Oversaw the analysis and development of complex and/or big features.
  • Reduced infrastructure costs by 75% and increased performance.
Technologies: PHP, Amazon Web Services (AWS), Jenkins, WordPress, JavaScript, CSS, MySQL, API Integration, Web Scraping, Gamification, APIs, Linux, WordPress Multisite, Apache, Bootstrap, MVC Frameworks, HTML5, Technical Leadership, Vanilla JS, Programming, Full-stack Development, Unit Testing, REST APIs, Fantasy & Daily Fantasy Sports Platforms

Full-stack Engineer

2017 - 2019
BrightIO
  • Built a Laravel platform that allowed the clients to track every aspect of their business in an easy but powerful way.
  • Created a Whatsapp and telegram bot capable of interacting with user requests.
  • Constructed an OCR system that takes financial statements and highlights critical information.
  • Developed a web platform capable of communicating with physical devices on the user's endpoint.
  • Crafted a web scrapper to collect data from several endpoints to automate data entry.
Technologies: Jenkins, WordPress, PHP, Amazon Web Services (AWS), Optical Character Recognition (OCR), Cordova, Python, MariaDB, Redis, Vue, Laravel, JavaScript, CSS, MySQL, Node.js, APIs, Linux, Laravel Livewire, Apache, Bootstrap, MVC Frameworks, HTML5, Full-stack, Chrome Extensions, Twilio API, Vanilla JS, Programming, Optimization, Full-stack Development, Bots, Unit Testing, REST APIs

Experience

MillonarIO

https://www.millonar.io/
This online lottery platform allows clients to manage every aspect of their business, from user operations to day-to-day business tracking and management.

Basically, it is an ecosystem of numerous devices (such as Android POS, Web POS, thermal printers, Bluetooth printers, etc.) that communicate via a network to conduct the operational part of the business.

Furthermore, it relies on arbitrary decimal precision computations, extensive reporting, data analysis, security, and a wide variety of settings. All of this enables business owners to manage their business operations parameters, especially to control their risk of monetary loss.

Bantasy

Bantasy is a fantasy sports league where you create a team based on real players in a given sport. You collect points according to the real-life players' stats (e.g., when they make a home run, you earn four points for your team, and so on). In the end, you win if your team of selected players scores the highest amount of points.

Servidores Activos

https://www.servidoresactivos.com
This is a web hosting, domain, and email provider that emphasizes reliability and speed. It's made with PhalconPHP and WordPress and supports multiple languages.

The platform is tied with many automation and user tracking tools to make improvements based on user data and ease the workflow process.

Forfin Intranet

An intranet to manage the employee database in a single place and automates many tasks such as permissions, notifications, vacations days, and payments.

Capital Project

https://capitalprestamos.com/
Capital Project consists of a loan management system where the business owner and managers can work with many aspects, such as loan management and historical data, clients, asset tasks automation, and powerful and dynamic reporting.

Sentiment Analysis Applied to Dominican Tweets

On this research project, we worked on how to detect sentiment based on tweets made from the Dominican Republic.

For this task, we built a multi-step pipeline and we employed human annotators with a strong background in linguistics working on a small number of texts from microblogs to compare the results.

The pipeline consisted of steps such as cleaning the text by removing URLs, hashtags, and mentions. This also included tokenizing and normalizing the tweets and then doing some calculations to analyze the tweet.

Business Bridge

This is an online real estate platform that allows people to find properties in its early development stages. Using this platform enables interested buyers to purchase at a lower rate or make a profit by selling it when finished.

Education

2019 - 2019

Flutter Developer in Software Development

Universidad Abierta Para Adultos (UAPA) - Santiago, Dominican Republic

2013 - 2017

Bachelor's Degree in Systems and Computing Engineering

Pontificia Universidad Católica Madre y Maestra - Santiago, Dominican Republic

2009 - 2011

IT Technologist Diploma in Information Technology

La Centenaria - Santiago, Dominican Republic

Certifications

JANUARY 2025 - PRESENT

React Native App Developer

Udemy

Skills

Libraries/APIs

REST APIs, Vuex, Vue, Node.js, jQuery, Pusher, Redis Queue, Socket.IO, React, Twilio API, Shopify API, Apple News API

Tools

Apache, Microsoft Visual Studio, Jenkins, Git, Apache Qpid, NGINX, Jira, Trello, Slack, Microsoft Power BI, Amazon Simple Notification Service (SNS), Amazon Simple Queue Service (SQS)

Languages

Python, PHP, JavaScript, CSS, HTML, HTML5, SQL, Sass, Ruby, C++, Go, TypeScript

Frameworks

Laravel, Laravel Livewire, Vanilla JS, Tailwind CSS, Divi, PhalconPHP, Bootstrap, Electron, Cypress, PHPUnit, Flutter, CodeIgniter, React Native, Filament PHP

Paradigms

Unit Testing, Agile, Search Engine Optimization (SEO), App Development, REST, Gamification, Mobile Development

Platforms

WordPress, Linux, Windows, cPanel, Visual Studio Code (VS Code), Amazon Web Services (AWS), AWS Lambda, CentOS, Ubuntu, MacOS, Android, Shopify, WordPress VIP, WooCommerce

Storage

MySQL, MariaDB, PostgreSQL, Redis, Redis Cache, Amazon S3 (AWS S3)

Other

APIs, MVC Frameworks, Programming, Full-stack Development, Bots, Cordova, Full-stack, API Integration, Web Scraping, Chrome Extensions, Technical Leadership, OAuth, eCommerce, Optimization, Fantasy & Daily Fantasy Sports Platforms, Windows 10, Yoast SEO, Galera Cluster, Elementor, Optical Character Recognition (OCR), Text Mining, Image Processing, Chrome Plugins, WordPress Multisite, AI-enabled Applications, FastAPI, Symphony, Web Hosting

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