Senior ReactJS Developer

Quantum Technologies. LLC; Chicago (IL); On-site; USD 130,000 - 190,000; Full time

Job summary

Quantum Technologies. LLC is seeking a senior frontend engineer in Chicago, IL to design, develop, and maintain scalable web applications using React.js and Next.js.

You will build reusable UI components, integrate with RESTful APIs and microservices, and collaborate with UX/UI designers to deliver accessible, high-performance interfaces. The role requires 8+ years of frontend development expertise, strong React.js experience, and proficiency with state management (Redux/Context API/Zustand),

Qualifications

• 8+ years of software development experience with strong frontend development expertise.
• 5+ years of hands-on experience with React.js.
• Strong experience with Next.js and modern frontend development frameworks.
• Hands-on experience with state management libraries such as Redux, Context API, or Zustand.
• Experience integrating REST APIs and GraphQL services.
• Understanding of microservices-based applications and event-driven architectures.
• Experience with frontend testing frameworks such as Jest, React Testing Library, or Cypress.
• Familiarity with Git, CI/CD pipelines, and Azure-based deployment environments.
• Strong debugging, performance optimization, and problem-solving skills.

Responsibilities

• Develop and maintain web applications using React.js and Next.js.
• Build reusable, maintainable, and responsive UI components.
• Integrate frontend applications with RESTful APIs and backend microservices.
• Collaborate with UX/UI designers to implement user-friendly interfaces.
• Optimize applications for performance, scalability, accessibility, and responsiveness.
• Participate in code reviews and contribute to coding standards and best practices.
• Troubleshoot and resolve application issues across development, testing, and production environments.
• Work closely with backend teams to implement secure and efficient integrations.
• Participate in Agile ceremonies including sprint planning, stand-ups, and retrospectives.
• Mentor junior developers and contribute to knowledge sharing within the team.
• Support deployment activities and production issue resolution as needed

Skills

Frontend development

UI components

Agile ceremonies

Code reviews

Performance optimization

Tools

React.js

Next.js

Redux

Context API

Zustand

GraphQL

REST APIs

Jest

React Testing Library

Cypress

Git

CI/CD

Azure

Job description

Key Responsibilities:

• Develop and maintain web applications using React.js and Next.js.
• Build reusable, maintainable, and responsive UI components.
• Integrate frontend applications with RESTful APIs and backend microservices.
• Collaborate with UX/UI designers to implement user-friendly interfaces.
• Optimize applications for performance, scalability, accessibility, and responsiveness.
• Participate in code reviews and contribute to coding standards and best practices.
• Troubleshoot and resolve application issues across development, testing, and production environments.
• Work closely with backend teams to implement secure and efficient integrations.
• Participate in Agile ceremonies including sprint planning, stand-ups, and retrospectives.
• Mentor junior developers and contribute to knowledge sharing within the team.

Support deployment activities and production issue resolution as needed

Required Skillset:

• 8+ years of software development experience with strong frontend development expertise.
• 5+ years of hands‑on experience with React.js.
• Strong experience with Next.js and modern frontend development frameworks.
• Hands‑on experience with state management libraries such as Redux, Context API, or Zustand.
• Experience integrating REST APIs and GraphQL services.
• Understanding of microservices-based applications and event‑driven architectures.
• Experience with frontend testing frameworks such as Jest, React Testing Library, or Cypress.
• Familiarity with Git, CI/CD pipelines, and Azure-based deployment environments.
• Strong debugging, performance optimization, and problem‑solving skills.

We are an equal opportunity employer. All aspects of employment including the decision to hire, promote, discipline, or discharge, will be based on merit, competence, performance, and business needs. We do not discriminate on the basis of race, color, religion, marital status, age, national origin, ancestry, physical or mental disability, medical condition, pregnancy, genetic information, gender, sexual orientation, gender identity or expression, national origin, citizenship/ immigration status, veteran status, or any other status protected under federal, state, or local law.