Full Stack Software Engineer

This role is best suited for a Middle to Senior Full Stack Software Engineer with experience building scalable web applications and an interest in AI-powered fintech products. The candidate should be proficient in JavaScript/TypeScript, React, Next.js, Node.js, Python, Express, FastAPI, PostgreSQL, MongoDB, Redis, AWS, Docker, Kubernetes, REST APIs, GraphQL, CI/CD, and AI/ML integrations. They should be familiar with developing end-to-end web applications, building financial APIs, integrating AI models, designing scalable microservices, optimizing application performance, and collaborating in a fast-paced startup environment.

1. How would you design a scalable microservices architecture for a financial automation platform?
   Answer: I would separate services by business domains (billing, payments, users, AI), keep them stateless, communicate through REST or event-driven messaging, and use centralized monitoring, authentication, and API gateways to ensure scalability and reliability.

2. What are the advantages of using Next.js over a standard React application?
   Answer: Next.js provides server-side rendering, static site generation, API routes, optimized image loading, improved SEO, and better performance while maintaining the flexibility of React.

3. How would you optimize the performance of a Node.js API handling millions of financial transactions?
   Answer: I would optimize database queries, implement Redis caching, use asynchronous processing for long-running tasks, apply connection pooling, scale horizontally, and continuously monitor latency with DataDog.

4. When would you choose PostgreSQL over MongoDB in a fintech application?
   Answer: PostgreSQL is preferred for transactional data requiring ACID compliance and complex relationships, while MongoDB is useful for flexible document storage, rapidly changing schemas, or semi-structured data.

5. How would you securely integrate OpenAI APIs into a production application?
   Answer: I would store API keys securely using secret management services, validate and sanitize user input, implement rate limiting and monitoring, handle failures gracefully, and avoid exposing sensitive customer data to external models.

6. What strategies do you use to ensure high test coverage in a full-stack application?
   Answer: I combine unit, integration, and end-to-end tests, mock external dependencies where appropriate, automate testing in CI/CD pipelines, and focus on critical business logic and user workflows.

7. How would you deploy and scale a containerized application using Docker and Kubernetes?
   Answer: I would containerize each service, define Kubernetes Deployments and Services, configure health checks, autoscaling, rolling updates, and use monitoring to maintain application reliability under varying workloads.

8. Describe your experience with GraphQL and how it differs from REST APIs.
   Answer: GraphQL allows clients to request exactly the data they need through a single endpoint, reducing over-fetching and under-fetching, whereas REST exposes multiple resource-based endpoints with fixed response structures.

9. How would you design a reliable billing workflow that must avoid duplicate payments?
   Answer: I would implement idempotency keys, database transactions, optimistic or pessimistic locking where appropriate, retry mechanisms with safeguards, and comprehensive audit logging to ensure consistency and traceability.

10. Tell us about a project where you integrated AI or machine learning into a production application.
    Answer: I integrated AI through external model APIs to automate business workflows, designed robust backend services around the models, implemented monitoring and fallback mechanisms, and evaluated results using user feedback and performance metrics.

SerpApi is the leading search data API platform, trusted by companies like Nvidia, Shopify, Perplexity, Adobe, and Samsung to integrate reliable search engine data into their applications. As a Junior Fullstack Engineer, you'll build and maintain APIs, features, and developer tools using Ruby, Ruby on Rails, MongoDB, JavaScript, AWS, and Linux, while contributing to code reviews, troubleshooting, and technical content. This is a fully remote, worldwide role with exceptionally competitive compensation, averaging $232,448 total annual compensation (including profit sharing), flexible working hours, extensive learning support, and a transparent, high-trust engineering culture. If you're eager to grow as a full-stack engineer in a remote-first company that values ownership, openness, and technical excellence, SerpApi is an outstanding place to accelerate your career.