Sergei Garcia, Developer in Monterrey, Mexico
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Sergei Garcia

Verified Expert  in Engineering

Front End Developer

Monterrey, Mexico
Toptal Member Since
December 9, 2020

A seasoned front-end engineer, Sergei Garcia boasts a decade of impact. Notably, he orchestrated a dynamic overhaul at through a 2.5-year front end refactoring to React, revolutionizing UX for its 35+ million users. Celebrated for creating high-performance applications with exemplary UX, Sergei's empathetic leadership and zest for continual growth establish him as more than a tech maestro. He's also an exceptional mentor who elevates every team he joins to new heights.


JavaScript, Front-end Development, HTML, TypeScript, Front-end, CSS, GraphQL...
JavaScript, React, Node.js, PHP, Laravel, Tailwind CSS, Backbone.js, TypeScript...
Interviewing, Mentorship, Computer Science, English, A11Y...




Preferred Environment

Node.js, Visual Studio Code (VS Code), Windows, MacOS, JavaScript, CSS, React

The most amazing...

...achievement of mine is leading a team migrating an educational platform from Backbone.js to React.js, vastly improving its UX for its 35+ million users.

Work Experience

Senior Software Engineer

2023 - PRESENT
  • Drove technical and product strategy, operations, architecture, and execution for a new product space with a potential revenue opportunity exceeding 100 million dollars.
  • Collaborated cross-functionally with product, design, and engineering teams, utilizing front-end programming languages like JavaScript, TypeScript, or ES6, along with proficiency in frameworks such as React, Vue, Angular, and CSS.
  • Mentored junior engineers, foster a collaborative environment, and continuously learn and improve technical and non-technical skills.
Technologies: JavaScript, Front-end Development, HTML, TypeScript, Front-end, CSS, GraphQL, ECMAScript (ES6), Angular, React, REST, Vue, Polymer

Lead Front-end Engineer

2021 - 2023
  • Led two transformational React/Tailwind/Laravel migration projects at Worked on the teacher portal and the internal customer service dashboard. Substantially improved user experience for 35+ million users and internal staff.
  • Pioneered significant operational enhancements, including a robust PR process, a coherent issue triage system, and a standardized design system component library.
  • Planned, executed, and released an administrative dashboard composed of at least 50 pages originally in Backbone.js to React in four months.
  • Championed a growth-oriented team environment by mentoring colleagues and enforcing engineering best practices.
Technologies: JavaScript, React, Node.js, PHP, Laravel, Tailwind CSS, Backbone.js, TypeScript, Redux, Chakra UI, Front-end Development, ECMAScript (ES6), REST, APIs, Web Performance Optimization (WPO), Front-end, CSS, Mentorship & Coaching, Mentorship, MacOS, GitHub, Full-stack, Redux Toolkit, HTML5, Visual Studio Code (VS Code), HTML, Single-page Applications (SPA), CSS-in-JS, JSON Web Tokens (JWT), Underscore.js, Sass, SCSS, SMACSS, CSS3, WebStorm, Docker, Webpack, Webpack 4, React Router, Velocity.js, Git, Git Flow, Linux, Ubuntu, Team Mentoring, Interviewing, English, Software Project Management, Basecamp, A11Y, Accessible Rich Internet Applications (ARIA), Web Accessibility, Architecture, Project Management, Next.js, Full-stack Development, Software Architecture

Interview Engineer Expert

2021 - 2022
  • Conducted interviews that evaluated fundamental computer science skills, grading software craftsmanship, and specific technologies.
  • Performed with a strict commitment to delivering a great candidate experience, offering guidance and encouragement to maximize candidate potential. All without compromising results that were neutral, objective, and opinion-free.
  • Specialized in over ten interview question sets across a wide variety of computer science topics, as well as front-end fundamentals.
Technologies: Interviewing, Mentorship, Computer Science, English, A11Y, Accessible Rich Internet Applications (ARIA), Web Accessibility, Architecture

JavaScript Architect

2020 - 2021
  • Spearheaded the development of RxVantage, a healthcare application that connected healthcare professionals by leveraging the Vue/Nuxt/Apollo/GraphQL stack.
  • Converted product requirements into action items that the front-end team could ingest; also participated in grooming discussions with the back-end team lead to identify blockers and suggested timeline and priority changes before each agile sprint.
  • Operated as a cornerstone for architectural decision-making. Consistently removed roadblocks and instilled best-practice guidelines through meticulous code reviews and frequent mentoring sessions for the front-end team.
Technologies: Scrum, Jira, GitHub, HTML, Front-end, Vue, CSS, Agile, Visual Studio Code (VS Code), MacOS, Unit Testing, React, Node.js, GraphQL, Nuxt.js, Vuex, Vue 2, JavaScript, Full-stack, Vuetify, Tailwind CSS, Front-end Development, ECMAScript (ES6), REST, APIs, Web Performance Optimization (WPO), Mentorship & Coaching, Mentorship, HTML5, Apollo Server, Single-page Applications (SPA), Apollo, CSS-in-JS, Styled-components, JSON Web Tokens (JWT), Sass, SCSS, SMACSS, CSS3, WebStorm, Docker, Webpack, Webpack 4, Vue Router, Git, Git Flow, Agile Workflow, Linux, Ubuntu, Team Mentoring, English, Software Project Management, A11Y, Accessible Rich Internet Applications (ARIA), Web Accessibility, Architecture, Next.js, Full-stack Development, Software Architecture

Senior Software Engineer

2019 - 2020
  • Led a ground-up development of the checkout flow from, leveraging Vue.js/Vuex/Nuxt/Apollo/GraphQL/Express/Node.js, improving network speed and developer experience by streamlining complex, relational data requests.
  • Recognized the team's knowledge gaps in GraphQL and Vue and hosted regular knowledge-building workshops to bridge the team's proficiency gap in GraphQL and Vue, earning accolades from peers and management for this proactive upskilling effort.
  • Served as a career growth coach for two junior engineers, facilitating monthly dialogues and goal-setting sessions for career progression within the company.
Technologies: Scrum, Jira, Single-page Applications (SPA), GitHub, HTML, Front-end, Vue, Nuxt.js, Agile, Visual Studio Code (VS Code), MacOS, Unit Testing, HTML5, CSS, Node.js, Express.js, GraphQL, Vue 2, Vuex, Apollo Server, Full-stack, Front-end Development, ECMAScript (ES6), REST, APIs, Web Performance Optimization (WPO), Mentorship & Coaching, Mentorship, JavaScript, Progressive Web Applications (PWA), Ember.js, Apollo, Vuetify, JSON Web Tokens (JWT), Underscore.js, SMACSS, CSS3, WebStorm, Webpack, Vue Router, Git, Git Flow, Agile Workflow, Linux, Team Mentoring, English, A11Y, Accessible Rich Internet Applications (ARIA), Web Accessibility, Architecture

Full-Stack Course Instructor

2018 - 2020
  • Acted as 1:1 mentor for students in a rigorous full-stack course capable of producing job-ready engineers utilizing the MongoDB/Express/Node.js/ React stack.
  • Achieved an exceptional track record characterized by 100% student satisfaction. This included creating and delivering over ten unique workshops that earned an average student rating of 9.5 / 10.
  • Inspired students to uphold best practices, develop robust portfolios, and gain confidence for networking and interviews.
Technologies: PostgreSQL, GitHub, HTML, Front-end, CSS, Enzyme, Visual Studio Code (VS Code), MacOS, Unit Testing, Express.js, Mentorship, React, MongoDB, Node.js, JavaScript, Redux, TypeScript, Front-end Development, ECMAScript (ES6), REST, APIs, SQL, Mentorship & Coaching, Full-stack, HTML5, Puppeteer, Single-page Applications (SPA), Apollo, CSS-in-JS, JSON Web Tokens (JWT), SMACSS, CSS3, Git, Interviewing, English, A11Y, Accessible Rich Internet Applications (ARIA), Web Accessibility, Computer Science

Full-stack Engineer

2017 - 2019
  • Improved and modernized Expedia's booking System. Adapted legacy booking process to follow modern functional programming practices and developed a global ad-serving platform built with Node.js.
  • Enhanced testing efficiency by introducing an automated testing set up with Selenium and Puppeteer, reducing testing time by 300%.
  • Managed and implemented a hospitality wizard MVP using React, Apollo, and GraphQL, rapidly learning GraphQL to ensure successful project delivery.
Technologies: Scrum, Jira, GitHub, HTML, Front-end, Enzyme, Agile, Visual Studio Code (VS Code), MacOS, SQL, Unit Testing, Redux, Puppeteer, Backbone.js, Hapi.js, Express.js, React, HTML5, CSS, Node.js, JavaScript, Full-stack, Front-end Development, ECMAScript (ES6), REST, APIs, Mentorship & Coaching, Windows, Mentorship, jQuery, Apollo Server, Single-page Applications (SPA), Selenium, Mocha, Chai, React Apollo, SMACSS, Grunt, CSS3, Webpack, React Router, Git, Agile Workflow, Linux, Team Mentoring, English, Full-stack Development, Mobile Development

Front-end Bootcamp Instructor

2016 - 2017
Desafio Latam
  • Functioned as a key instructor for Desafio Latam's full-stack web developer bootcamp, specializing in delivering comprehensive learning content for the front-end development modules, empowering the next generation of web developers.
  • Created the entire course syllabus and materials used during the course.
  • Evaluated student exercises and provided customized feedback to each student, as well as action plans to resolve areas of opportunity.
Technologies: GitHub, HTML, Front-end, Mentorship, CSS, HTML5, JavaScript, Redux, Front-end Development, ECMAScript (ES6), REST, Bootstrap 3, Mentorship & Coaching, Windows, AngularJS, jQuery, Single-page Applications (SPA), SMACSS, CSS3, Git, English

Front-end Developer

2016 - 2017
Inflection Point
  • Developed new components for a company in the education sector using the Salesforce CMS and AngularJS. Achievements include reducing unit testing development time by over 80% by migrating component structure to a microservices approach.
  • Maintained the company website by regularly fixing bugs and adding new functionality including enhancements that improved scrolling and loading performance by over 40%.
  • Migrated a JavaScript bundler from a legacy Grunt build to a new Gulp build that was 40% smaller in configuration size making it easier to maintain—by at least 50% faster—and used current and up-to-date plugins.
Technologies: GitHub, HTML, Front-end, Agile, Windows, Unit Testing, Express.js, Redux, HTML5, Bootstrap 3, CSS, AngularJS, JavaScript, Bootstrap, Front-end Development, ECMAScript (ES6), REST, jQuery, Single-page Applications (SPA), APIs, Mocha, Chai, Jasmine, Less, Sass, SCSS, SMACSS, Grunt, Gulp, WebStorm, Git, Agile Workflow, English, Trello

Front-end Developer

2014 - 2016
  • Developed a hybrid HTML5 mobile application for a Forbes 500 agriculture company using Ionic/Cordova, AngularJS, Couchbase, and ArcGIS in a transformative role.
  • Embraced senior responsibilities, like identifying and acting upon areas for improvement in performance, testing, and development processes, which led to remarkable rendering performance improvement of three to five times.
  • Built a prototype iOS hospital demo application via C# Xamarin Forms and accomplished within a demanding four-week deadline.
Technologies: Scrum, Jira, GitHub, HTML, Front-end, AngularJS, Windows, Unit Testing, Xamarin.Forms, JavaScript, HTML5, CSS, Bootstrap 3, Bootstrap, Front-end Development, jQuery, Agile, Backbone.js, Single-page Applications (SPA), APIs, Mocha, Chai, Jasmine, Less, Sass, SCSS, SMACSS, BEM, Grunt, Gulp, CSS3, WebStorm, GSAP, Velocity.js, Git, Agile Workflow, English, Trello, C#, Mobile Development, a robust educational platform serving around 35+ million users monthly. Facing a rapidly growing user base, the platform was in dire need of a technology overhaul. As the lead front-end developer, I was at the forefront of this upgrade, writing over 60% of the new codebase myself and directing a small team of two other engineers in the process. Our task: a comprehensive refactoring from Backbone.js to React.

My role expanded beyond coding responsibilities. Guided by Basecamp's Shape Up methodology over traditional Agile and Scrum, I assumed substantial ownership of the project. It was my responsibility to precisely dissect complex requirements, furnish time estimates, and communicate progress updates directly to upper management. Additionally, I conceived and brought significant operational enhancements to fruition, including a robust PR process, a coherent issue triage system, and a standardized design system component library.

Throughout this herculean two-plus-year task, my passion for quality, dedication, and effective communication had a profound impact on the broader organization, inspiring other teams to elevate their performance. This dedication to excellence earned praise from management and peers alike.

At Deviget, I led the development of RxVantage as a JavaScript Architect, a medical application innovatively bridging the communication gap between pharmaceutical reps and healthcare providers. Leveraging the Vue/Nuxt, Apollo GraphQL, Vee Validate, lodash, and Vuetify stack, the platform could provide instant access to an expansive network of industry representatives and enable efficient appointment scheduling, real-time request handling, and meeting logistics automation.

Alongside heavy coding, I managed and mentored a mixed-experience team of two developers, fostering an environment of continuous learning and boosting development speed and tech stack understanding. The merits of which were widely recognized by the managerial team. The impact was palpable: we successfully digitized a traditionally offline communication process, significantly enhancing the healthcare-pharmaceutical interaction landscape.


As the senior software engineer at DigitalOnUs, I spearheaded a migration project for, a leading US public information provider. I orchestratee revampinf the checkout flow, transitioning it from Ember to an upgraded tech stack comprising Vue.js, Express, Apollo, and GraphQL. This switch was triggered by the need for better performance, speed, and maintainability.

The use of GraphQL not only improved network speed by reducing request round trips but also vastly enriched the developer experience due to its inherent ease of handling complex, relational data requests. I also dedicated a significant portion of my time to rigorous code reviews, fostering a culture of high coding standards within the mixed geography team.

Despite the team's initial unfamiliarity with Vue and GraphQL, I adopted a proactive mindset and took a lead role in mastering these tools. I then shared this expertise with the team through a series of bi-weekly workshops aimed at raising the team's skill level to match the demands of our ambitious project. My active mentoring and focus on skill alignment were highly commended by team members and management alike.

I was involved in two key projects for during my tenure at Luxoft. One was maintaining and improving's legacy jQuery codebase concerning the website's booking process. I introduced modern programming strategies to refactor parts of the sprawling, monolithic code into functional components, significantly boosting code maintainability.

Simultaneously, I participated in developing an ad-serving platform for, founded on Node.js and Express.js. I spearheaded a major improvement by creating an automated testing pipeline using Selenium and Puppeteer, which expedited testing time by an impressive 300%. This strategic intervention uplifted the development quality while reducing delivery timelines.

During my engagement at Luxoft, I was at the forefront of developing a key MVP hospitality wizard for HomeAway (now Vrbo), a substantial player in the online vacation rental marketplace. This groundbreaking project introduced me to advanced technology stacks such as React, Apollo, and GraphQL, operating on a Hapi.js/GraphQL server.

Coming into the project, I led the development, presenting myself with the challenge of mastering GraphQL, a novel technology during the project's inception. Displaying adaptability and quick learning capabilities, I transitioned proficiently into this new technology. This instance was a testament to my resourcefulness and sustained effort towards staying up-to-date with emerging trends in the field.
2010 - 2013

Bachelor's Degree in Software Development

Universidad Tecmilenio - Monterrey, NL, Mexico


Mobile Web Specialist



TOEIC English Certification (950/990)



Vue 2, Vuex, React, Backbone.js, jQuery, Vue, Chai, Underscore.js, React Router, Node.js, Puppeteer, Velocity.js, GSAP, Chart.js, Polymer


GitHub, Mocha, Grunt, Gulp, WebStorm, Webpack, Git, Basecamp, Jira, Redux Toolkit, React Apollo, Webpack 4, Trello


Bootstrap 3, AngularJS, Redux, Tailwind CSS, Bootstrap, JSON Web Tokens (JWT), Nuxt.js, Ember.js, Express.js, Vuetify, Jasmine, Hapi.js, Laravel, Selenium, Next.js, Angular


JavaScript, CSS, HTML5, HTML, ECMAScript (ES6), Less, Sass, SCSS, CSS3, GraphQL, SQL, TypeScript, PHP, C#


Agile, Web Performance Optimization (WPO), Unit Testing, REST, SMACSS, BEM, Scrum, Agile Workflow, Mobile Development


MacOS, Windows, Visual Studio Code (VS Code), Docker, Netlify, Linux, Ubuntu


MongoDB, PostgreSQL

Industry Expertise

Project Management


Progressive Web Applications (PWA), Mentorship, Enzyme, Front-end, Single-page Applications (SPA), APIs, Chakra UI, Full-stack, Front-end Development, Mentorship & Coaching, CSS-in-JS, Vue Router, Git Flow, Team Mentoring, Interviewing, English, A11Y, Accessible Rich Internet Applications (ARIA), Web Accessibility, Computer Science, Architecture, Apollo Server, Apollo, Styled-components, Gatsby, Software Project Management, Full-stack Development, Software Architecture, Xamarin.Forms

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