Senior Fullstack Engineer - React/JS

Remote position, only for professionals based in Argentina or Uruguay

RYZ Labs is seeking a Full Stack Engineer (React / JavaScript) to join one of our clients’ teams building intelligent, secure, and scalable digital experiences. In this role, you will contribute to modernizing existing applications while building new user-facing features using React and modern JavaScript technologies.

You will work closely with cross-functional teams including backend, product, and platform engineers to deliver reliable and scalable solutions. The ideal candidate will help evolve the front-end architecture while navigating a legacy environment and integrating modern technologies.

Responsibilities

• Develop and maintain modern React-based user interfaces using clean, reusable, and maintainable code.

• Build responsive and intuitive UI components using React and Material UI (MUI).

• Implement styling using SCSS while maintaining consistent design and UI standards.

• Integrate front-end applications with REST APIs and backend services.

• Collaborate with backend engineers to deliver end-to-end product functionality.

• Participate in the modernization of legacy applications and help migrate existing features to modern front-end frameworks.

• Maintain and improve existing codebases while ensuring scalability, performance, and maintainability.

• Write and maintain unit and integration tests to ensure code quality.

• Review code and provide constructive technical feedback to team members.

• Debug and resolve production issues across the application stack.

• Contribute to front-end architecture decisions and development best practices.

• Participate actively in Agile ceremonies, including stand-ups, sprint planning, and retrospectives.

• Create and maintain technical documentation.

• Stay current with modern front-end development practices and tooling.

Qualifications

• 5+ years of professional experience in software development.

• Strong experience with React and modern JavaScript frameworks.

• Proficiency in JavaScript and/or TypeScript.

• Experience building UI using Material UI (MUI).

• Strong experience with SCSS or modern CSS frameworks.

• Experience integrating REST APIs into modern web applications.

• Proficiency with Git version control.

• Experience building responsive and user-friendly web applications.

• Experience working in Agile development environments.

• Strong collaboration and communication skills across engineering teams.

Nice to Have

• Familiarity with ASP.NET WebForms and Razor templating.

• Ability to read and understand C# code.

• Experience with Gulp or similar asset pipeline tools.

• Experience with testing frameworks such as NUnit or Jest.

• Familiarity with Azure DevOps and NuGet.

• Experience working in legacy modernization projects.