Front-End Engineer (React)

About the role

Blockchain.com is looking for a Front-End Engineer with strong React skills to join their team in Paris. The role centers on building and maintaining the user-facing interfaces that power the company's blockchain and financial services products. The engineer will partner with product managers, UX designers, and back-end developers to create reliable and intuitive web experiences. Candidates should thrive in a collaborative environment where product requirements evolve quickly and clean code is valued.

Key facts

What you'll do

1. Develop and maintain React-based user interface components that power the Blockchain.com platform and its web applications.

2. Collaborate with UX designers to translate design mockups and interactive prototypes into fully functional web pages.

3. Optimize application performance to ensure fast rendering times and smooth, responsive user interactions across all devices.

4. Write clean, maintainable, and well-documented front-end code that follows the team's established coding conventions and standards.

5. Participate in code reviews to ensure code quality, share knowledge, and help maintain consistency across the codebase.

6. Debug and resolve front-end issues reported by users or identified through internal quality assurance testing procedures.

7. Integrate RESTful APIs and WebSocket connections to enable real-time data display and dynamic content updates in the user interface.

8. Contribute to the company's design system and component library that is shared across multiple web products and teams.

9. Work with back-end engineers to define clear API contracts and ensure smooth communication between front-end and back-end services.

10. Stay current with emerging front-end technologies and evaluate their potential value for improving the product and developer experience.

11. Assist in setting up and continuously improving the front-end build pipeline, development tooling, and local environment configurations.

12. Support the deployment process by writing and maintaining front-end specific tests, including unit and integration test suites.

13. Refactor legacy front-end code to improve maintainability, reduce technical debt, and align with current best practices and patterns.

14. Mentor junior engineers and contribute to a positive team culture through knowledge sharing and collaborative pair programming sessions.

Requirements

1. Proficiency in JavaScript, including modern ES6+ syntax, arrow functions, closures, and asynchronous programming patterns using promises and async/await.

2. Strong hands-on experience with React, including hooks, context API, component composition, and popular state management libraries.

3. Solid understanding of HTML5 and CSS3, with the ability to build responsive, accessible, and cross-browser compatible layouts.

4. Familiarity with version control systems, particularly Git, and standard branching workflows such as feature branches and pull requests.

5. Experience working with RESTful APIs and a solid understanding of HTTP methods, status codes, and request-response patterns.

6. A degree in computer science, software engineering, or a related technical field, or equivalent practical experience in software development.

7. Ability to work effectively in a collaborative team environment with cross-functional stakeholders including designers and product managers.

8. Strong problem-solving skills and a consistent attention to detail when building interactive, accessible, and user-friendly web interfaces.

9. Experience with modern front-end build tools, module bundlers, and package managers such as npm or Yarn is expected.

10. Understanding of web performance optimization techniques including lazy loading, code splitting, tree shaking, and asset minification.

Nice to have

1. Experience with TypeScript and its static type system for building scalable and maintainable front-end applications.

2. Familiarity with state management solutions such as Redux, Zustand, or MobX for managing complex application state.

3. Prior exposure to blockchain or cryptocurrency-related products and platforms is considered a strong advantage.

4. Knowledge of testing frameworks like Jest, React Testing Library, or Cypress for front-end test automation and coverage.

5. Experience with design systems and component-driven development workflows using tools such as Storybook for documentation.

6. Familiarity with CI/CD pipelines and continuous integration practices for automated front-end build and deployment workflows.

Skills & tools

1. React.js and its ecosystem including React Router, Suspense, lazy loading, and popular UI component libraries.

2. JavaScript and TypeScript for writing type-safe, scalable, and maintainable application logic and front-end code.

3. CSS preprocessors such as Sass or styling libraries like styled-components and CSS modules for component styling.

4. Git for version control, code collaboration, branching strategies, and pull request workflows in a team setting.

5. Webpack, Vite, or similar module bundlers for managing front-end builds, asset pipelines, and development configurations.

6. REST APIs and asynchronous data fetching patterns using fetch, Axios, or React Query for server communication.

7. Browser developer tools and performance profiling utilities for debugging, auditing, and optimizing web applications.

Practical notes

1. The role is based in the Paris office, with standard business hours and occasional flexibility for focused work periods.

2. Candidates should be prepared to participate in team standups, sprint planning sessions, and retrospective meetings on a regular basis.

3. The hiring process includes technical assessments, coding challenges, and interviews with members of the front-end engineering team.

4. Blockchain.com values diversity and encourages applicants from all backgrounds and experiences to submit their applications.

5. The team operates in an agile development cycle with regular sprints, iterative releases, and continuous improvement practices.

6. Onboarding includes access to internal documentation, mentorship programs, and ongoing training and professional development resources.

7. The company offers competitive benefits including health coverage, retirement plans, and professional development budgets for growth.

8. This position requires on-site presence in Paris and does not include a remote work arrangement.