Delta6Labs - Senior Backend Engineer - Node.js

As a Senior Backend Engineer at Delta6Labs, you will design, build, and maintain scalable, secure, and high-performance backend systems for our fintech platform. You join a high-growth innovator building white-label crypto exchanges, NFT marketplaces, crypto wallets, and MT5/MT4 integrations for financial institutions and enterprises. You'll work closely with product and front-end teams to deliver reliable APIs and services, with exposure to cloud infrastructure, distributed systems, and modern development practices.

What you'll do

• Design, develop, and maintain robust server-side applications using Node.js
• Build and maintain scalable, low-latency RESTful APIs
• Design systems for high availability, performance, and reliability
• Work with databases such as PostgreSQL, MongoDB, and Redis
• Implement authentication, authorization, and data security best practices
• Optimize backend services for performance, scalability, and cost efficiency
• Integrate with third-party services and APIs such as messaging, email, and payments
• Collaborate with product, front-end, and QA teams to understand and deliver requirements
• Participate in code reviews, technical discussions, and documentation
• Write and maintain unit, integration, and end-to-end tests
• Work with CI/CD pipelines and containerized environments using Docker
• Collaborate with platform and DevOps teams on cloud deployments and Kubernetes-based systems
• Implement and work with message queues and streaming systems such as RabbitMQ, Kafka, AWS SQS/SNS, or Azure Service Bus
• Support real-time features using WebSockets or event-driven architectures

What you bring

• 5 to 7 years of backend development experience with strong recent experience in Node.js
• Deep understanding of Node.js core concepts, asynchronous programming, and event-driven architecture
• Hands-on experience with Node.js frameworks such as Express.js or similar
• Strong experience in API design, microservices, and inter-service communication
• Proficiency in SQL and NoSQL databases and data modelling
• Experience with authentication and authorization mechanisms such as JWT and OAuth
• Familiarity with security best practices including encryption at rest and in transit, and OWASP guidelines
• Experience profiling and optimizing backend services and database queries
• Hands-on testing experience using Jest or Mocha/Chai
• Exposure to cloud platforms such as AWS or Azure
• Experience with real-time systems and messaging or event-driven architectures
• Strong problem-solving, communication, and collaboration skills
• Bachelor's or Master's degree in Computer Science or a related field, or equivalent practical experience

Nice to have

• Familiarity with blockchain-based systems or crypto platforms
• Experience in FinTech, Banking, or Payments, especially high-scale or regulated systems
• Experience working in high-traffic, distributed systems

About Delta6Labs

Delta6Labs is a high-growth fintech innovator building scalable, cutting-edge solutions in crypto, trading, and blockchain. We provide white-label crypto exchanges, NFT marketplaces, crypto wallets, and MT5/MT4 integrations that empower financial institutions, brokers, and enterprises to expand their digital offerings.