Senior Backend Developer (Node.js)

OnHires; Paris; Sur place; EUR 60 000 - 100 000; Plein temps

Résumé du poste

An innovative firm is seeking a Senior Backend Developer to tackle complex technical challenges and build high-performance backend systems. In this role, you will leverage your extensive Node.js expertise to design and maintain scalable services and APIs, ensuring performance and reliability. You will collaborate with cross-functional teams to create cloud-native solutions and integrate third-party APIs, all while adhering to best practices in software development. If you're passionate about backend architecture and eager to make a significant impact, this opportunity is perfect for you.

Prestations

Flexible working hours

Health insurance

Remote work options

Professional development budget

Team-building activities

Gym membership

Work-from-home stipend

Paid time off

Company events

Tech conferences attendance

Qualifications

• 5+ years of backend development experience with Node.js expertise.
• Strong knowledge of REST APIs and microservices architecture.
• Experience with cloud platforms and containerized deployments.

Responsabilités

• Design and maintain scalable backend services and APIs using Node.js.
• Integrate third-party APIs and collaborate with cross-functional teams.
• Optimize databases and implement monitoring for production systems.

Connaissances

Node.js

JavaScript/TypeScript

REST APIs

MySQL/PostgreSQL

Redis

RabbitMQ/Kafka

AWS/GCP/Azure

Docker

GraphQL

Test-Driven Development (TDD)

Formation

Bachelor's degree in Computer Science or related field

Outils

Docker

Kubernetes

Terraform

Prometheus

Grafana

ELK Stack

Jest

Mocha

Cypress

Swagger/OpenAPI

Description du poste

We’re looking for a Senior Backend Developer with 5+ years of professional experience and 3+ years of hands-on Node.js expertise to build and scale high-performance backend systems. You’ll work on complex technical challenges while collaborating closely with cross-functional teams.

Responsibilities

Backend Development & Architecture:
️ Design, develop, and maintain scalable backend services and APIs using Node.js, focusing on performance, security, and reliability.
️ Architect REST/GraphQL APIs with best practices for rate limiting, idempotency, and versioning.
️ Implement event-driven architectures using message brokers (RabbitMQ, Kafka) and real-time systems (WebSockets/Socket.io).
️ Optimize MySQL/PostgreSQL databases through query tuning, indexing, and sharding strategies.
️ Build and maintain caching layers with Redis (e.g., cache invalidation, clustering, Lua scripting).

System Integration & Collaboration:
️ Integrate third-party APIs (payment gateways, authentication services) with fault tolerance and retry logic.
️ Collaborate with frontend and DevOps teams to design cloud-native solutions (AWS/GCP/Azure) and containerized deployments (Docker/Kubernetes).
️ Write clean, maintainable code following SOLID principles and participate in rigorous code reviews.

Performance & Troubleshooting:
️ Identify and resolve bottlenecks in distributed systems, including database latency, message queue tuning, and API performance.
️ Implement monitoring and logging (Prometheus, Grafana, ELK Stack) for production systems.
️ Conduct root cause analysis (RCA) for critical issues and implement preventive measures.

Process & Best Practices:
️ Advocate for test-driven development (TDD) and write automated tests (Jest, Mocha, Cypress).
️ Contribute to CI/CD pipelines (GitHub Actions, Jenkins) and infrastructure-as-code (Terraform).
️ Document technical designs, API specs (Swagger/OpenAPI), and system architecture.

Technical Requirements

Core Skills:
️ 5+ years in backend development, with 3+ years of commercial Node.js experience.
️ Expertise in Node.js frameworks: Express.js, NestJS, Fastify.
️ Advanced proficiency in JavaScript/TypeScript (ES6+, async/await, streams).
️ Deep understanding of REST/WebSocket APIs and microservices architecture.

Databases & Tools:
️ MySQL/PostgreSQL: Complex query optimization, replication, ORMs (Sequelize/TypeORM).
️ Redis: Cache strategies, pub/sub, and persistence configurations.
️ RabbitMQ/Kafka: Message queuing, event streaming, and dead-letter handling.
DevOps & Cloud:
️ Experience with AWS/GCP/Azure (Lambda, EC2, S3, Cloud Functions).
️ Proficiency in Docker and basic knowledge of Kubernetes.
️ Familiarity with infrastructure-as-code (Terraform, CloudFormation).

Bonus Skills:
️ Knowledge of serverless architectures (AWS Lambda, Serverless Framework).
️ Experience with GraphQL (Apollo Server, schema design).
️ Understanding of security practices (JWT, OAuth2, encryption).
Soft Skills:
️ Advanced English for clear technical documentation and team collaboration.
️ Strong problem-solving skills and attention to detail.