Gonzalo García Costoya

Frontend Developer

+54 9 223 668 6246 • gcostoya02@gmail.com • Mendoza, Argentina • linkedin.com/in/gonza-garcia • github.com/gonza-garcia

Professional Summary

Frontend Developer with more than 6 years building production React applications for US and Argentine companies. For more than three years I worked on United Airlines' real-time flight-operations console, using React, Redux Toolkit, TypeScript, Vite, and AG Grid Enterprise, among others.

I have solid experience building and maintaining apps and libraries following good practices, with well-tested and accessible code. This includes cross-team library migrations, refactoring, component splitting, and comprehensive project modernization (toolchain, testing, and performance).

Advanced English with more than three years of daily communication with US-based clients. I have heavily adopted AI agentic development as my main way of working day to day, using tools like GitHub Copilot and OpenCode. Without compromising code quality, I rely on skills and MCPs to research, implement, review and test the output.

Open to Senior or Semi-Senior remote Frontend opportunities, and continuously learning across the React ecosystem and modern frontend tooling.

Skills

FrontendReact (versions 16 to 19, with cross-team migration of shared libraries), TypeScript, Redux Toolkit (migration from Redux and Redux Saga to Redux Toolkit and RTK Query), React Query, AG Grid (data grids in the real-time flight operations console), Sass/SCSS, Responsive design, Web accessibility (semantic HTML, ARIA, contrast, focus and keyboard navigation)
EngineeringVite (migration from Create React App to Vite 6), Vitest (behavior and integration tests over complete user flows, migrated from Jest), React Testing Library (integration tests over complete user flows), Storybook, Playwright (E2E suite on a personal project), REST APIs, Git and GitHub, CI/CD and feature flags (Harness, with pipelines and per-environment flags)
WorkflowAgile/Scrum (2-week sprints, daily, refinement and retros), Code review and mentoring (PR review and mentoring within the team)
LanguagesSpanish (Native), English (Advanced, 3+ years of daily communication with US-based client)

Work Experience

GlobantFrontend Developer | February 2020 - July 2026
United Airlines (Flight Following console)February 2023 - July 2026
  • Modernized and scaled United Airlines' FLIFO Flight Following console, an event-driven, real-time React app for flight operations that today replaces more than 30 legacy programs in production.
  • Identified that one component could be encapsulated in its own library and created and published Flight Card: a reusable, self-contained React library with its own Redux store and API layer. Maintained it through more than 50 published versions, and today it is used in production by more than 3 teams within the company.
  • Led a cross-team migration from React 16 to React 19, coordinating synchronized upgrades across two teams and three shared internal libraries.
  • Designed a gradual migration plan: from Redux to Redux Toolkit as the state manager, and from Redux Saga to RTK Query for data fetching. It simplified and organized hundreds of generators and effect handlers, slowly saving thousands of lines of boilerplate code.
  • Migrated the build toolchain from Create React App to Vite 6 and the test runner from Jest to Vitest 2, enforcing high V8 coverage thresholds of more than 70% in statements with SonarQube reporting. Kept the tests focused on app behavior and not on implementation details. Integration tests covered complete user flows.
  • Cut initial bundle size by about 30% with aggressive code splitting and lazy-loading dozens of modal chunks, through a custom wrapper over React.lazy, dynamic import and Suspense, used across multiple points in the app.
  • Built a real-time WebSocket client layer with a Redux-slice connection state machine and auto-reconnect, consuming endpoints across 7 environments, from development to production.
  • Refactored large components into smaller modules and separated logic from presentation, improving maintainability and enabling smoother parallel team work.
BBVA Seguros ArgentinaApril 2021 - January 2023
https://www.bbvaseguros.com.ar
  • Built a standalone React and Redux insurance-quoting application from scratch, covering eight distinct insurance services, and defined the stack selection, library choices, and workflow design.
  • Embedded custom React components as WordPress plugins within an Elementor-built marketing site, collaborating with two frontend developers on the integration layer between WordPress and React, including, among others, a carousel and a highly interactive header menu.
  • Created about 10 reusable React components with BBVA-branded variants, such as buttons, headers, menus, forms, dropdowns and sliders, implementing the official BBVA BentonSans type system and brand color palette.
AccionaFebruary 2020 - March 2021
  • Proposed and built a React app to generate Outlook HTML emails faster, cutting per-email time from about six hours to one hour. The team kept using it after my engagement without hiring a replacement.
  • Hand-coded HTML emails for Outlook and restyled a ServiceNow internal web app with SCSS, collaborating directly with the client under Agile workflows.

Education

Digital House - Full Stack Web Development BootcampFebruary 2019 - December 2019
8-month intensive in-person bootcamp, with complementary Udemy online courses
UTN Mar del Plata - Higher Technician in ProgrammingFebruary 2007 - July 2008
2 years, 17 of 22 subjects completed (incomplete)

Certifications

Anthropic AI Fluency
AI fluency certification covering practical use of AI tooling in development workflows

Personal Projects

HTML Email Builderhttps://html-email-builder.pages.dev/ | 2021
Outlook HTML email builder with a syntax-highlighting editor and live preview, published as a static SPA.
Smart Facehttps://smart-brain-front.pages.dev/ | 2020
Face-detection app with signup and login: React SPA against a custom Node/Express API with SQLite, deployed across two platforms.