Software Engineer III - Front-End Developer - ReactJS

Testing Site - JPMC; Buenos Aires; In loco; ARS 1.800.000 - 4.000.000; Tempo pieno

Descrizione del lavoro

Testing Site - JPMC in Buenos Aires, Argentina is seeking a seasoned Software Engineer to build modern web apps using React, Redux Toolkit, and GraphQL. You’ll collaborate across product, design, and backend teams to deliver secure, accessible experiences at scale.

You’ll work with GraphQL services, implement robust testing, CI/CD, and performance optimizations while mentoring peers and contributing to engineering best practices.

Competenze

• Production-grade React experience (5+ years).
• Strong JavaScript/TypeScript fundamentals.
• Experience with Redux/Redux Toolkit and GraphQL client caches.
• Hands-on GraphQL integration in front-ends (Apollo Client or urql).
• Testing across unit, integration, and component tests.
• Semantic HTML, modern CSS, responsive design.
• Frontend build tooling and linting/formatting.
• Auth flows, secure storage, and security basics.
• Git and Agile teamwork.
• Ability to use AI coding assistants and craft clear prompts.

Mansioni

• Build, test, and maintain responsive React applications.
• Implement state management with Redux Toolkit and GraphQL client caches.
• Integrate GraphQL services using Apollo Client or urql; manage caching, pagination, retries.
• Collaborate with backend teams on schema and API contracts; ensure WCAG-compliant UI.
• Write high-quality tests (Jest, RTL) and automate via CI/CD.
• Profile and optimize performance and GraphQL usage.
• Participate in architecture/design reviews and document components.
• Mentor peers and contribute to engineering best practices.
• Leverage AI tools to accelerate coding workflows.

Conoscenze

React

TypeScript

Redux Toolkit

GraphQL (Apollo)

Jest/RTL

CI/CD

Git

AI coding tools

Accessibility

Web security basics

Strumenti

Webpack/Vite

Nx/Turborepo

Storybook

GraphQL clients

Descrizione del lavoro

About the role

We’re seeking a 602 Software Engineer to build and evolve modern web applications using React and Redux, with a primary focus on GraphQL for data access. You’ll collaborate with product, design, and platform teams to deliver secure, performant, and accessible user experiences at scale. Experience with micro-frontend (MFE) architectures is a plus.

What you’ll do

• Build, test, and maintain responsive React applications using modern patterns (hooks, functional components, context where appropriate).


• Implement predictable state management with Redux/Redux Toolkit, including middleware, selectors, and efficient store design; integrate cleanly with GraphQL client caches.


• Integrate with GraphQL services using Apollo Client or urql: define queries, mutations, and subscriptions; manage normalized caching, pagination (cursor/relay style), error handling, retries, and optimistic updates.


• Partner with backend teams on schema and API contracts (SDL), versioning, and performance patterns (query batching, persisted queries, avoiding n+1 issues).
  Partner with design to implement accessible (WCAG-compliant) and consistent UI aligned to a design system.


• Write high-quality, well-tested code (Jest, React Testing Library); automate via CI/CD and follow trunk-based development or GitFlow as applicable.


• Profile and optimize performance (bundle size, code splitting, memoization, virtualization, lazy loading) and GraphQL network usage (field-level policies, cache keys).


• Participate in architecture/design reviews, code reviews, and contribute to shared libraries and component systems.
  Document components and patterns for reusability; mentor peers and contribute to engineering best practices.


• Leverage AI-assisted development tools and prompt engineering techniques to accelerate coding workflows, generate boilerplate, write tests, refactor code, and improve documentation quality.
  

Must-have qualifications

• Professional experience building production-grade React applications (typically 5+ years or equivalent depth).


• Strong JavaScript and TypeScript fundamentals; ESNext, modules, and typing best practices.
  Deep experience with Redux/Redux Toolkit and app-level state architecture; familiarity with coordinating Redux state and GraphQL client caches.


• Hands-on experience integrating GraphQL in production front-ends (Apollo Client or urql): queries, mutations, subscriptions, fragments, cache normalization and policies, pagination strategies, error boundaries, and GraphQL Code Generator.


• Testing expertise across unit, integration, and component tests; familiarity with mocking GraphQL operations and contract testing.


• Solid grasp of web fundamentals: semantic HTML, modern CSS (CSS-in-JS, Modules, or utility-first), responsive design.


• Front-end build tooling (Webpack/Vite), package managers, and linting/formatting (ESLint, Prettier).


• Understanding of auth flows (OAuth/OIDC, JWT), secure storage patterns, and front-end security basics (CSP, CORS, security headers).


• Version control with Git and collaborative development in Agile environments.


• Ability to effectively use AI coding assistants (e.g., GitHub Copilot, LLM Suite) and craft clear, context-rich prompts to improve productivity, code quality, and problem-solving efficiency.

Nice to have

• Micro-frontend architectures (Webpack Module Federation, single-spa, import maps); experience with shared runtime and dependency governance.


• Monorepo tooling (Nx, Turborepo) and shared UI libraries/design systems (Storybook).
  Node.js for front-end build tooling or BFFs; familiarity with GraphQL gateways and schema stitching/federation concepts.


• Observability for front-end (metrics, logging, tracing, error monitoring) and feature flagging/experimentation.


• Advanced accessibility expertise (ARIA patterns, keyboard navigation, screen reader support).


• Cloud and CDN basics; understanding of edge caching and performance optimization for APIs and assets.
  

How we work

• Customer-centric, iterative delivery with clear acceptance criteria and measurable outcomes.


• Code reviews, pair/mob programming as needed, and continuous improvement through retrospectives.


• Emphasis on reliability and resilience: meaningful monitoring, alerting, and on-call participation where applicable.