Staff Research ML Engineer (Europe-based/Remote)

What you'll be doing

• Own complex ML problems end-to-end - Take on the hardest technical challenges (like fine-tuning LLMs to maximize clinical outcomes) from initial exploration through production deployment and real-world iteration.
• Drive technical strategy in your domain - Define how we approach model development, evaluation, and optimization for clinical AI applications.
• Build and optimize production LLM systems - Design and implement fine-tuning pipelines, preference optimization (RLHF, DPO), and rigorous evaluation frameworks for clinical use cases.
• Work deeply across the full AI stack - From data preparation and model training through deployment, monitoring, and iteration in production environments.
• Influence across teams - Partner with Product, Clinical, and Engineering teams to shape technical decisions and ensure we’re solving the right problems.
• Raise the technical bar - Mentor engineers, establish best practices, and help define what excellent ML engineering looks like at Sword.
• May lead 1-2 engineers on specific projects, providing technical direction and mentorship.

What you need to have

• Deep expertise in production ML systems - You’ve built and shipped ML systems that users depend on, with a track record of solving complex technical problems.
• Production LLM experience - You’ve fine-tuned, evaluated, and deployed LLMs in production environments.
• Experience with preference optimization - You’ve implemented techniques like RLHF, DPO, or similar approaches in production settings.
• Strong ML fundamentals - You understand when to use different ML approaches, can design rigorous evaluation frameworks, and make principled technical tradeoffs.
• End-to-end ownership - You’ve taken ambiguous, complex problems from initial exploration through production deployment and ongoing iteration.
• Excellent engineering skills - You write production-quality code, understand distributed systems, and can debug complex ML pipelines.
• Communication and influence - You can drive technical decisions across teams and explain complex tradeoffs to technical and clinical stakeholders.

What we would love to see

• Experience with healthcare AI or clinical applications and the unique challenges of building ML for high-stakes domains.
• Track record of designing evaluation frameworks for LLMs in specialized domains.
• Contributions to the ML community through open source, technical writing, or other knowledge sharing.

To ensure you feel good solving a big Human problem, we offer

• A stimulating, fast-paced environment with lots of room for creativity;
• A bright future at a promising high-tech startup company;
• Career development and growth, with a competitive salary;
• The opportunity to work with a talented team and to add real value to an innovative solution with the potential to change the future of healthcare;
• A flexible environment where you can control your hours (remotely) with unlimited vacation;
• Access to our health and well-being program (digital therapist sessions);
• Remote or Hybrid work policy;
• To get to know more about our Tech Stack, check here.

The interview process

• 30-minute call with the recruiter
• 30-minute call with an initial screener
• 1 take-home assignment (to be delivered within 1 week)…