Java backend developer Jobs in Hamburg

fanblast is a fast-growing SaaS that connects creators with their fans through WhatsApp and SMS. We empower influencers and creators to build meaningful fan relationships, monetize exclusive content, and foster genuine engagement. Our product focuses on ease of use, seamless monetization, and scalability, transforming the way creators connect with their audience. With a collaborative, agile, and creative work culture, each team member's input helps shape our innovative product. Join fanblast, where your work will help define the future of creator-fan interactions and bring real value to influencers across various industries, including entertainment, social media, and more.

We are seeking an experienced Senior Backend Developer to join our engineering team. You will be responsible for designing, developing, and maintaining scalable backend services that power our tool. This role involves working with a modern microservices architecture, integrating with third-party services, and ensuring high performance and reliability of our backend systems.

Aufgaben

Responsibilities

Design, develop, and maintain robust, scalable backend APIs and microservices

• Architect and implement efficient database schemas and queries for PostgreSQL
• Implement caching strategies using Redis to optimize application performance
• Build and maintain message queue integrations using RabbitMQ and NATS
• Integrate with third-party payment processors (Stripe, Solidgate, PayPal)
• Develop and maintain integrations with messaging platforms (Telegram, WhatsApp)
• Implement media processing pipelines and services
• Write clean, maintainable, and well-documented TypeScript/JavaScript code
• Collaborate with frontend developers and other team members to deliver features
• Participate in code reviews and maintain high code quality standards
• Debug and resolve production issues in a timely manner
• Optimize application performance and scalability
• Design and implement RESTful APIs following best practices
• Work with Docker and containerized applications
• Implement proper error handling, logging, and monitoring

Qualifikation

Required Technical Skills

Core Technologies

• Node.js (v24+) --> Advanced proficiency (Building high-performance, scalable applications)
• TypeScript --> Strong experience (Type-safe development and large-scale application maintenance)
• Express.js --> Strong experience (Building RESTful APIs and web services)
• JavaScript (ES6+) --> Strong experience (Modern JavaScript features and best practices)

Databases & Data Storage

• PostgreSQL --> Database design, query optimization, migrations
• Redis --> Caching strategies, session management, pub/sub
• Couchbase --> NoSQL/document database operations

Message Queues & Event Systems

• RabbitMQ --> Message queue implementation and management
• NATS --> Event-driven architecture and messaging

Infrastructure & DevOps

• Docker --> Containerization and Docker Compose
• Microservices Architecture --> Designing and maintaining service-oriented systems
• Nginx --> Reverse proxy configuration and load balancing
• Linux/Unix --> Server administration and deployment

Third-Party Integrations

• Payment Processing (Stripe, Solidgate, PayPal integration experience)
• Messaging Platforms (Telegram Bot API, WhatsApp integration)
• Cloud Services (AWS SDK, Superbase & Betterstack)
• API Integration (RESTful APIs, webhooks, authentication)

Development Tools & Practices

• Git (Version control and collaborative development)
• Yarn/NPM (Package management)
• Code Quality (ESLint, Prettier, code review practices)
• Testing (Unit testing, integration testing)
• API Documentation (OpenAPI/Swagger, API design best practices)

Preferred Qualifications

• 5+ years of professional backend development experience
• Experience with microservices architecture and service communication patterns
• Strong understanding of database design principles and query optimization
• Experience with payment gateway integrations and PCI compliance considerations
• Knowledge of real-time messaging systems and WebSocket protocols
• Experience with media processing and file uploads
• Understanding of security best practices (authentication, authorization, encryption)
• Experience with monitoring, logging, and observability tools
• Familiarity with CI/CD pipelines and automated deployment processes
• Experience working in agile development environments

Nice to Have

• Experience with GraphQL APIs
• Knowledge of Kubernetes for container orchestration
• Experience with message broker patterns (pub/sub, queues)
• Understanding of event sourcing and CQRS patterns
• Experience with performance testing and optimization
• Knowledge of internationalization (i18n) implementation
• Experience with WebRTC or real-time communication protocols

Benefits

Why you should join us

• Great workplace in the center of Hamburg (hybrid: 3 days per week in office).
• Flat hierarchies, fair compensation & flexible working hours
• You'll be part of an ambitious team that values speed, persistence and results.
• You'll work with top creators, helping them transform how they connect and monetize.
• fanblast is at the center of the creator economy boom — a $250B+ market that's reshaping culture.
• We're a startup with momentum: lean, ambitious, and ready to scale

Providing interactive experiences to the world. In all aspects of entertainment.