Senior Backend Developer (Core)

As a Senior Backend Developer at Paxful, you will be responsible for designing and developing backend services primarily using PHP, while also engaging with Go and Node.js. Your role will involve creating RESTful APIs, collaborating with product managers to define requirements, ensuring high performance and scalability of services, troubleshooting issues in production, and contributing to migrating legacy systems. Additionally, you'll implement database optimizations and mentor junior developers, playing a crucial role in our growing team.

To qualify for the Senior Backend Developer position at Paxful, candidates should possess over 5 years of backend development experience with a strong focus on PHP (preferably PHP 7.4+). Familiarity with frameworks like Laravel or Symfony is highly recommended. Experience in Go and Node.js, along with proficiency in SQL (like PostgreSQL or MySQL) and exposure to NoSQL databases, is also essential. Knowledge of best practices in API integration and a solid understanding of secure coding practices will help you thrive in this role.

In the Senior Backend Developer position at Paxful, you'll work with a diverse set of technologies. Your primary focus will be on PHP, while you will also explore Go and Node.js. Key tools and platforms include Kubernetes and Terraform for deployment and monitoring, along with GitLab and Docker for version control and containerization. Familiarity with RESTful API design, message queues (like RabbitMQ or Kafka), and monitoring tools (such as Prometheus and Grafana) will empower you further in this role.

At Paxful, we embrace a fully remote work environment, allowing talented professionals from around the world to join our team. You can expect flexible working hours with a 4-hour overlap in Eastern Time (EST), which promotes a work-life balance while collaborating with cross-functional teams. Our culture is built on collaboration, innovation, and supporting one another, allowing you to contribute to impactful projects and grow alongside other skilled engineers.

Paxful is deeply committed to the professional growth and development of its employees, including Senior Backend Developers. You will have opportunities to take on complex projects, mentor junior developers, and collaborate on innovative solutions within the fintech and crypto space. Furthermore, our supportive work culture encourages continuous learning and sharing of knowledge, ensuring you can advance your skills and career in a meaningful way.

When answering this question, elaborate on specific projects where PHP was your primary language. Discuss the frameworks you used, the kind of applications you built, and how you optimized the performance of your PHP code. Highlight any challenges you faced and how you overcame them, bringing attention to your problem-solving skills and adaptability.

Explain your understanding of scalable architectures and strategies like load balancing, database optimization, and effective use of microservices. Discuss how you’ve implemented these strategies in past projects and share examples where you successfully improved system performance. Concrete examples from your experience will strengthen your response.

In your response, outline your systematic approach to debugging. Mention tools or techniques you employ, such as logging, monitoring tools, and code reviews. Provide a specific example of a production issue you tackled and how your actions improved system reliability. This showcases your analytical skills and technical expertise.

Discuss your proficiency in designing RESTful APIs, focusing on principles such as resource-based design, versioning, and documentation. Share insights into how you’ve handled API integration in previous projects, mentioning any challenges you encountered and how you ensured the API remained efficient and easy to use for clients or other services.

Talk about the resources you rely on to stay informed, such as tech blogs, podcasts, webinars, or community contributions. You might also mention attending conferences and participating in forums. Share how you’ve applied new learnings in your work, which emphasizes your commitment to continuous improvement in your field.

Mention GitLab, Docker, Kubernetes, and any other tools you’re experienced with. Discuss how you use each tool within the development lifecycle, from version control to continuous integration and deployment. Provide specific examples of how using these tools has improved your workflow and project outcomes.

Respond by citing a particular project where teamwork with various roles was pivotal. Highlight how communication and collaboration contributed to the project's success, and touch on your role in facilitating teamwork and bridging gaps between differing team perspectives.

Share your understanding of secure coding principles and best practices, such as input validation, authentication mechanisms like OAuth and JWT, and regular security audits. Provide examples of how you’ve integrated these practices in your projects to ensure the robustness of the applications you developed.

Discuss your familiarity with microservices, including how you have designed, developed, and deployed microservices in previous positions. Mention specific technologies used and the benefits observed, such as improved scalability or maintainability. This reflects your technical know-how in contemporary backend development.

Emphasize your experience in guiding and mentoring less experienced team members. Discuss techniques you use, such as code reviews, pair programming, and providing resources for learning. Share a success story of a junior developer you helped grow, highlighting your impact on their career development.