Senior UI Developer – (ReactJS / NestJS)
Summary
Senior UI Developer building scalable, responsive web applications in a hybrid São Paulo role. Day to day spans front-end development with React.js and Next.js backed by NestJS services, all in TypeScript, plus writing unit tests with Jest/React Testing Library and mentoring junior developers.
Location: São Paulo, Brazil — Hybrid
Job Description
We are seeking a highly skilled and experienced Senior UI Developer with a strong background in React.js, Next.js, NestJS, TypeScript, and unit testing. The ideal candidate has a proven track record of building scalable, responsive, and high-performance web applications.
This role requires a collaborative mindset, strong attention to detail, and the ability to take ownership of UI development initiatives from concept through implementation.
Key Responsibilities
- Design, develop, and maintain modern, scalable front-end applications using React.js and NestJS.
- Write clean, efficient, maintainable, and well-documented code using TypeScript.
- Implement and maintain unit tests using frameworks such as Jest and React Testing Library to ensure code quality and reliability.
- Optimize applications for performance, scalability, responsiveness, and overall user experience.
- Partner closely with UX/UI designers, back-end developers, and Product Owners to deliver seamless user experiences.
- Mentor junior developers and review their work to ensure adherence to engineering best practices and coding standards.
- Participate actively in code reviews, architectural discussions, and Agile ceremonies, including sprint planning and retrospectives.
- Stay current with front-end technologies, frameworks, and industry trends to promote innovation and engineering best practices across the team.
Required Skills & Qualifications
- 10+ years of overall software development experience.
- Strong expertise in React.js and NestJS.
- Proficiency in Next.js, TypeScript, and modern JavaScript (ES6+).
- Hands-on experience with unit and automated testing tools and frameworks, such as Jest, Mocha, and Cypress.
- Strong understanding of HTML5, CSS3, Sass/SCSS, and responsive web design.
- Familiarity with state management libraries such as Redux, Zustand, or Recoil.
- Experience integrating applications with RESTful APIs and GraphQL.
- Knowledge of CI/CD pipelines and version control platforms such as Git, GitHub, and GitLab.
- Excellent problem-solving skills and strong attention to detail.
- Strong verbal and written communication skills, with the ability to collaborate effectively across teams.
Education
- Bachelor’s or Master’s degree in Computer Science, Engineering, or a related field.