VTEX Flutter Fullstack Engineer

**Role description** **Fullstack Software Developer** **Who We Are:** Born digital, UST transforms lives through the power of technology. We walk alongside our clients and partners, embedding innovation and agility into everything they do. We help them create transformative experiences and human\-centered solutions for a better world. UST is a mission\-driven group of 29,000\+ practical problem solvers and creative thinkers in more than 30 countries. Our entrepreneurial teams are empowered to innovate, act nimbly, and create a lasting and sustainable impact for our clients, their customers, and the communities in which we live. With us, you’ll create a boundless impact that transforms your career—and the lives of people across the world. Visit us at UST.com. **You Are:** UST is searching for a Fullstack Software Developer who will develop and maintain custom apps in VTEX IO and Store Themes; configure Checkout, Promotions, Master Data, OMS, Catalog, and Payments. **The opportunity:** * Build high\-performing storefronts with React/TypeScript, optimizing Core Web Vitals, SSR, and caching. Integrate VTEX APIs (REST/GraphQL) and FastStore (preferred) using a headless commerce approach. * Backend \& Architecture: Design and implement microservices and REST/GraphQL APIs (Node.js/TypeScript), with ORM and relational databases (e.g., PostgreSQL/MySQL). * Ensure security (OAuth2/JWT, rate limiting, input validation, secrets management) and observability (logs, metrics, traces). Document with OpenAPI/Swagger and maintain high quality with unit/integration testing (Jest; Cypress for end\-to\-end). * Mobile \- Flutter Design and develop Flutter apps with Clean Architecture, state management (BLoC/Cubit/Riverpod), modularization, and performance best practices (profiling, lazy loading, custom painters where applicable). * Integrate mobile payment methods, push notifications, WebSockets/real\-time, and Firebase (Auth, Firestore, Messaging) wher