Senior Fullstack Developer (Java / React), Brazil
Confirmed on the employer's own hiring board on Oct 17, 2026. First seen by Alion on Aug 28, 2026. CI&T scores A on the Alion truth index.
We’re looking for a talented Senior-Master Full-Stack Developer with strong expertise in React and Java (Spring Boot). You’ll play a crucial role in designing, building, and supporting enterprise-scale web applications and microservices that are performant, secure, and user-centric.
What You’ll Do:
Design, develop, unit test, and integrate full-stack application components.
Build scalable web applications using React on the frontend and Java 21 / Spring Boot on the backend.
Implement RESTful APIs, microservices, and integrations with enterprise systems.
Collaborate with UX/UI, product, architecture, and QA teams within an Agile environment.
Create and maintain architecture, design, and system documentation.
Ensure code quality, performance, and security, including OAuth2, OIDC, and JWT.
Work with MySQL, Hibernate, Spring Data, and Spring Security.
Support production systems using Kibana and APM tools, and participate in on-call rotation when needed. Demonstrated experience in monitoring and troubleshooting applications is essential.
What We’re Looking For:
Solid experience with full-stack development.
Strong hands-on experience with React, modern JavaScript (ES6+), DOM APIs, and JSON.
Proficient in backend development with Java,(including old versions),and Spring Boot; recent hands-on experience is required.
Experience with microservices and enterprise integration patterns.
Solid experience with RDBMS (MySQL or similar) and SQL.
Good understanding of web security standards including JWT, authentication, and other security concepts.
Excellent problem-solving, debugging, and communication skills;
Candidates should demonstrate a structured approach to problem-solving and clarity in communication.
Comfortable working in the EST time zone.
Production support experience, including a strong understanding of application error handling and standard practices.
Nice to Have:
Familiarity with micro-frontend architecture and component libraries (e.g., Storybook, styled-components).
Knowledge of event-driven architecture and Kafka; experience is preferred.