About the company:

Kiefer Tech , the technology arm of Kiefer , leverages over 20 years of engineering heritage from the Green Energy sector to deliver cutting-edge AI, robotics, and enterprise solutions across Greece and the EU. We build sovereign AI infrastructure that keeps data within EU borders, respect privacy, and delivers tangible business impact. Guided by our core values—innovation, quality, and long-term client partnerships—we create enterprise-grade AI infrastructure, the first true Greek Large Language Models, and intelligent automation solutions that empower organizations to thrive. Our strategic collaboration with NVIDIA combines sustainable infrastructure expertise with world-class AI technology, creating an ecosystem that fosters innovation, strengthens Greece’s technological sovereignty, and generates real impact across industries. Join us and help build the AI-powered world of tomorrow.

About the role: We are seeking a Senior Machine Learning Engineer to design, optimize, and scale our core AI systems powering Sophea and Kiefer’s multi-product platform. This role combines deep hands-on ML engineering with systems thinking and cross-functional collaboration. You will work on production-grade ASR pipelines, Greek-language LLM performance, agentic AI frameworks, and cost-efficient inference at scale—while helping set technical standards and elevating the ML practice across the organization.

Your work will directly impact product performance, customer experience, and our ability to scale AI solutions across public sector and enterprise use cases in Greece and beyond.

What you will do:

• Build and scale production-grade ASR and LLM pipelines, improving throughput, latency, and reliability while ensuring full data sovereignty.
• Improve model performance through dataset-centric optimization, expanding Greek-language and domain-specific capabilities.
• Design and deploy scalable multi-agentic AI systems to automate complex enterprise document analysis and decision workflows.
• Drive cost and performance optimization for model inference, reducing cost-per-task through quantization, caching, and smart routing.
• Define and uphold ML engineering standards, including evaluation frameworks, ML CI/CD, testing, and mentorship across the ML team.

What you will need:

• Deep experience in AI orchestration with tools like LangGraph, CrewAI, or MCP for building multi-agent systems.
• Proven ability to use vLLM, TensorRT, or quantization (AWQ/GGUF) to scale throughput.
• ASR Expertise and hands-on work with Whisper or Kaldi, specifically optimizing for non-English languages.
• Proficiency in synthetic data generation and fi-tuning for specialized domains (Legal/Finance).
• Advanced Python, PyTorch, and Docker skills; familiarity with MLOps and CI/CD for AI.
• Ability to design systems, not just write scripts, with a focus on data sovereignty.
• High agency and ownership, AI curiosity and structured mindset

What is there for you:

• Hybrid office set up / Remote work
• Competitive compensation package
• Group medical health insurance plan
• Work with most innovative state-of-the-art Greek AI technology
• Opportunity to grow and learn from the best AI industry experts
• All the tools and equipment you need to excel at your role