Senior Node.js Developer

This role suits a Senior Backend Developer with 5+ years of experience in Node.js and Nest.js, especially those comfortable with microservice architecture, high-load systems, and technologies like RabbitMQ, Redis, and MongoDB. Ideal candidates are fluent in English (C1), have solid testing (TDD) practices, and are familiar with REST, GraphQL, and WebSockets. Bonus if experienced with CI/CD, Kubernetes, and TypeScript.

1. What are the key features of ECMAScript 6 that you frequently use in Node.js development?
   Common ES6 features include arrow functions, destructuring, template literals, let/const, classes, and promises—each improving code readability and maintainability.

2. How does NestJS differ from Express, and why would you choose it?
   NestJS is built on top of Express but adds TypeScript support and a modular architecture inspired by Angular, making it ideal for scalable enterprise applications.

3. Can you explain the benefits and drawbacks of using WebSockets vs REST APIs?
   WebSockets allow real-time, bi-directional communication, making them ideal for live apps, while REST is simpler and better suited for standard request/response interactions.

4. Describe your experience implementing GraphQL in a Node.js environment.
   I've used Apollo Server with Node.js to build GraphQL APIs, handling resolvers, schemas, and integrating with authentication and data sources for optimized queries.

5. What are some strategies for optimizing performance in high-load Node.js applications?
   Caching with Redis, connection pooling, clustering, efficient database queries, async operations, and load balancing are key strategies for handling high traffic.

6. How do you use RabbitMQ in a microservices architecture?
   RabbitMQ handles asynchronous messaging between services, enabling decoupled communication via message queues and supporting retries, dead-lettering, and routing logic.

7. What are the advantages of using Redis, and in what scenarios have you applied it?
   Redis is an in-memory store used for caching, pub/sub, and session storage due to its low latency and support for various data structures.

8. How do you ensure code quality and test coverage in your Node.js projects?
   By following TDD principles, writing unit/integration tests with tools like Jest or Mocha, using linters, and automating tests in CI pipelines.

9. What challenges have you faced with MongoDB or MySQL in production, and how did you address them?
   Challenges include query optimization, indexing issues, and schema design; I’ve used monitoring tools, proper indexing, and normalization/denormalization techniques.

10. Describe your approach to building and deploying containerized Node.js microservices.
    I use Docker to containerize services, define multi-stage builds, manage orchestration with Kubernetes, and automate deployments using CI/CD pipelines.

BrainRocket is looking for a Senior Node.js Developer to join their in-office team in Valencia, Spain, building high-performance platforms for fintech, iGaming, and marketing. You'll work with cutting-edge tech like Node.js, Nest.js, GraphQL, Redis, and RabbitMQ in a fast-paced, product-driven environment. The role offers relocation support, 24 vacation days, a fitness corner, and language learning perks. If you're ready to help shape bold digital products with a global team of 1,300 innovators, this is your move.