Senior Backend Engineer - AI Systems (m/f/x)

We are seeking a Senior Backend Engineer to design and build the backend layers that power our platforms, with a focus on secure APIs, data processing pipelines, and resilient storage systems. You will play a key role in shaping our backend architecture, ensuring it is robust, scalable, and secure. This role requires both technical leadership and hands-on implementation, working closely with cross-functional teams to deliver end-to-end solutions.

You'll collaborate closely with Frontend Developers, Data Scientists, AI Engineers, and Product Managers to deliver seamless end-to-end solutions. 

In this role, you will have the opportunity to:

• Design, develop, and maintain secure, scalable backend services, APIs, and microservices.
• Architect and implement backend layers including API Gateway & Load Balancer, AI Agent layer, Data Intelligence, Data Extraction, and Data Storage.
• Build resilient Python services with frameworks like LangGraph, Celery, PydanticAI, and enforce typed schemas for data quality.
• Implement event-driven processing and long-running job orchestration with retries, backoff, and idempotency.
• Develop integration points with external connectors/SDKs and ensure validation at ingestion.
• Optimize backend components for performance, reliability, and cost efficiency at scale.
• Work with diverse data stores (e.g., Elasticsearch, Neo4j, DynamoDB, MySQL) ensuring fit-for-purpose storage, security, and compliance.
• Implement monitoring, observability, and tracing for backend pipelines (Prometheus, Grafana, centralized logging, Langfuse, Arize Phoenix).
• Collaborate with frontend, AI/ML, product, and infra teams to deliver seamless solutions.
• Document backend architecture, APIs, and workflows for internal reference and onboarding.
• Stay current with backend/cloud technologies and recommend improvements.

• 5+ years of professional experience in backend software development, with deep expertise in Python.
• Proven experience building scalable backend systems with Python services, Celery workers, event-driven architectures, and API Gateway/ALB.
• Solid understanding of microservices patterns, event-driven systems, and schema validation with tools like PydanticAI.
• Hands-on experience with SQL and NoSQL databases (MySQL, DynamoDB, Neo4j) and search engines (Elasticsearch).
• Familiar with Infrastructure as Code (IaC) and CI/CD pipelines for safe, automated releases.
• Strong grasp of software engineering principles, security best practices, and data lifecycle management. 
• Experience with observability and monitoring tools (Prometheus, Grafana, centralized logging, Langfuse, Arize Phoenix).
• Comfortable working with Git-based workflows in collaborative environments.
• Excellent problem-solving and debugging skills.
• Strong communication and collaboration abilities.
• Strong communication and collaboration abilities, with effective written and spoken English.

• Experience with Docker and container orchestration.
• Knowledge of cloud-based AI services (e.g., Amazon Bedrock, Azure AI Foundry) and RAG quality frameworks (RAGAS).
• Familiarity with graph-based queries and hybrid search use cases.
• Exposure to DevOps or SRE practices, including blue/green deployments, WAF/caching at the edge, and automated rollbacks.

• 4-Day Work Week & up to 24 Days Paid Vacation – More time to recharge
• Monthly Benefits Allowance – €40/month in vouchers for fitness and other perks with Probonio
• Competitive Compensation – Fair salary and comprehensive benefits. 
• Flexible Work Arrangements – Work the way that suits you. Professional Development – Access to training and certifications. 
• Team Events – Bi-annual company events and Quarterly team lunch get-togethers. 
• Work Abroad Flexibility – Remote work from the EU or selected non-EU countries for up to 8 weeks a year with travel insurance coverage

• In-Office Collaboration: Work from the office two days a week
• Manage Your Own Hours: Flexibility to work around your needs as long as team goals are met.