Senior Backend Engineer; Node.js​/NestJS – Greenfield Product

Senior Backend Engineer (Node.js/NestJS):
Building and maintaining scalable backend services and system architecture for a new greenfield product with an accent on API design, system scalability, and AI-augmented engineering. Focus on designing clean backend architectures, solving complex technical challenges, and mentoring engineers.

Location:

Hybrid role based in Berlin or Munich, Germany with remote work options within Germany.

Castle Tech is a product company focused on building innovative software solutions with a modern engineering culture and AI integration.

• Build and maintain scalable backend services using Node.js and NestJS
• Design clean system architecture for a new production product
• Own features from concept through deployment and define APIs and backend infrastructure
• Collaborate with frontend engineers, product managers, and designers
• Establish development standards, CI/CD pipelines, and engineering best practices
• Mentor engineers through code reviews and technical feedback

• Location:
  Must be based in Germany or able to work hybrid from Berlin or Munich
• 5+ years of backend engineering experience with Type Script, Node.js, and NestJS
• Experience designing scalable backend architectures and working with relational databases
• Strong understanding of software design principles and maintainable systems
• Experience with Git, CI/CD pipelines, Docker, and agile methodologies
• Strong communication skills in English (minimum B2 level)

• Experience with microservices or event-driven architectures
• Experience building greenfield or standalone products
• Familiarity with AI-related components and AI service integration
• Conversational German

• Work on a greenfield product with real technical ownership
• Modern engineering environment with AI-forward culture
• Hybrid work model with office and remote options in Berlin or Munich
• Choice of work gear (Mac Book or Windows)
• Structured onboarding and coaching for growth and development
• Collaborative and ambitious engineering team