Senior Backend Engineer - AI & Search Platform

We’re building a brand-new AI Engineering Team . And this is your chance to help shape it from the ground up.
As a Senior Backend Engineer - AI & Search Platform , you’ll design and scale the backend foundation that powers AI-driven discovery and intelligence in our product. You’ll connect systems, ingest and structure data, and make it searchable and meaningful for our users - all while ensuring performance, reliability, and maintainability.

You’ll turn state-of-the-art AI into real product impact, integrating established ML frameworks, vector and keyword search engines, and transformer-based architectures into production-ready systems.
If you’re ready to build the backbone of intelligent software where engineering excellence meets applied AI, this is your moment to lead.

Haiilo is a leading employee communications and engagement platform that empowers companies to foster a more connected, engaged, and aligned workforce. Our solutions enable businesses to streamline internal communications, enhance employee advocacy, and boost overall company culture. We make it easy for over 1000 organisations to share important information, measure engagement, and amplify employee voices.

What we are looking for:

You’re a senior engineer who enjoys combining deep backend experience with a passion for applied AI. You think in systems, not silos - from architecture to operations, and you know how to turn ambitious ideas into reliable, scalable software.

You bring:

• 5+ years of hands-on experience building and operating Spring Boot (Java) services backed by a SQL database
• Hands-on experience with keyword and vector search engines
• Solid understanding of Transformer architectures and how to use them effectively in production
• Experience with at least one widely used ML framework (e.g. PyTorch, TensorFlow, or similar)
• Proven ability to communicate complex technical concepts clearly — and collaborate across engineering, product, and AI teams in excellent English
• Huge interest in Retrieval-Augmented Generation (RAG) (experience with hybrid search and reranking systems) and cutting-edge AI technologies
• Bonus for hands-on experience with PostgreSQL, Elasticsearch, Python, AI agents, Kubernetes (k8s), Java profiling, and Google Cloud Platform (GCP)

We encourage you to apply even if your profile does not yet meet all the requirements for the position. At Haiilo we support your personal development as well as your individuality, no matter what background you have.

Responsibilities:

• Impact the design of backend services that integrate AI models and search technologies at scale
• Actively shape our AI data integration strategy and its implementation
• Build and optimize retrieval pipelines that make information searchable, contextual, and actionable
• Evaluate, select, and operationalize AI frameworks and libraries for real-world use cases
• Collaborate closely with frontend and product teams to deliver intelligent, end-to-end user experiences
• Ensure excellence in code quality, performance, observability, and reliability- setting the bar for engineering practices across the team
• Act as a technical mentor and thought partner, driving knowledge-sharing and fostering a culture of learning and innovation

What we offer:

👩🏼‍💻Flexibility & Teamwork: We love our hybrid setup and meet to work on-site at least 1 day/week, with Wednesdays as the designated in-office day. While Wednesday is the minimum, we recommend spending 2 (or more) days in the office each week.

🎉Company Vibe: We value spending time together, so you’ll get to join regular team socials, themed afterworks (e.g. Pride Month, Cultural Awareness Month, etc.), in-person workshops, and our annual company week in Hamburg 🥳

🚀Growth: At Haiilo, we are passionate about personal and professional growth. Our leadership is dedicated to helping you improve every day, through individual and group workshop sessions, financial support for training, conferences, books, etc. and external learning resources (e.g. access to Blinkist)

🌴Time off: Depending on your location, we offer up to 30 vacation days to take some well-deserved time off. Our employees in all locations get 2 annual company-wide self-care days on top of the normal vacation days (because we love what we do, but we also love a healthy work-life balance!)

🌟Health & wellbeing: To promote physical and mental wellbeing, we not only offer health insurance for all locations and a discount for sports memberships but also access to Nilo.health. ’Cause healthy employees = happy employer!

🌏Sustainability: We only have one planet: We understand the importance of sustainability. We are a carbon-neutral company, our merch is sustainable and we offer exclusive discounts for sustainable brands through FutureBens

🫂Diversity & Inclusion: We are committed to a diverse and inclusive environment. As an international and multicultural team with different skills, ideas and experiences, we actively work to represent and promote diversity in the company