Software Engineer III - Front-End Developer - ReactJS
Aumni
Software Engineering
Buenos Aires, Argentina
Posted on Mar 20, 2026
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.
J.P. Morgan is a global leader in financial services, providing strategic advice and products to the world’s most prominent corporations, governments, wealthy individuals and institutional investors. Our first-class business in a first-class way approach to serving clients drives everything we do. We strive to build trusted, long-term partnerships to help our clients achieve their business objectives.
We recognize that our people are our strength and the diverse talents they bring to our global workforce are directly linked to our success. We are an equal opportunity employer and place a high value on diversity and inclusion at our company. We do not discriminate on the basis of any protected attribute, including race, religion, color, national origin, gender, sexual orientation, gender identity, gender expression, age, marital or veteran status, pregnancy or disability, or any other basis protected under applicable law. We also make reasonable accommodations for applicants’ and employees’ religious practices and beliefs, as well as mental health or physical disability needs. Visit our FAQs for more information about requesting an accommodation.
J.P. Morgan’s Commercial & Investment Bank is a global leader across banking, markets, securities services and payments. Corporations, governments and institutions throughout the world entrust us with their business in more than 100 countries. The Commercial & Investment Bank provides strategic advice, raises capital, manages risk and extends liquidity in markets around the world.
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.