Senior Machine Learning Engineer - AI in London

As one of the world's top three credit ratings agencies, Fitch Ratings plays a critical role in global capital markets by providing credit analysis, ratings, research, and commentary to financial market participants. For over 100 years, Fitch Ratings has been creating value for global markets through its rigorous analysis and deep expertise.

Fitch Ratings is seeking a Senior Machine Learning Engineer to join our new AI Innovation teams in London—where we're building the AI-powered future of financial analysis from the ground up. This is about designing and shipping breakthrough generative AI systems, agentic workflows, and intelligent platforms that will transform how credit analysis happens and how global financial markets operate.

As a Senior ML Engineer, you'll be a technical force on the team—building sophisticated ML systems, driving innovation through hands-on work, mentoring engineers, and helping establish the technical standards that will scale across the organization. We need ML engineers who thrive on hard problems and greenfield opportunities.

Build breakthrough ML systems with real impact:

• Design and ship production generative AI platforms, multi-agent systems, and intelligent automation that will process billions in credit decisions.
• Work on problems at the frontier of applied AI while seeing your work directly change how analysts and financial markets operate.

Work at the cutting edge of ML technology:

• Experiment with the latest LLMs and foundation models.
• Implement novel RAG architectures, build agentic systems, fine-tune neural networks, and leverage enterprise-scale GPU clusters and cloud infrastructure.

Technical leadership without the bureaucracy:

• Lead projects, mentor junior engineers, shape technical direction, and influence architectural decisions through your expertise and results.

Toronto's world-class AI ecosystem:

• Work in one of the world's premier AI research hubs alongside Vector Institute researchers.
• Attend cutting-edge ML meetups and conferences.

Greenfield innovation with enterprise backing:

• Build net-new ML systems from scratch with the freedom to experiment boldly, fail fast, and push boundaries.

Solve sophisticated ML challenges:

• Tackle hard problems at the intersection of NLP, document intelligence, reasoning systems, agentic workflows, and production-scale deployment.

Clear growth trajectory:

• High visibility to senior leadership, mentorship from experienced ML architects, and clear paths to Lead ML Engineer or Principal ML Engineer roles.

We'll Count on You To:

• Design and build transformative ML systems using PyTorch, modern ML frameworks, and large language models.
• Drive AI innovation through hands-on technical work.
• Lead projects and drive technical excellence.
• Mentor and elevate junior engineers.
• Build production ML infrastructure.
• Champion ML governance and operational excellence.
• Collaborate across teams effectively.
• Stay at the bleeding edge of emerging ML technologies.

What You Need to Have:

• Strong ML engineering expertise – 6+ years of professional experience building production AI/ML systems.
• Advanced generative AI and LLM experience.
• Deep ML technical skills – Strong proficiency in Python and ML algorithms.
• Bachelor's degree in Machine Learning, Computer Science, Data Science, Applied Mathematics, or related field (Master's or PhD is strongly preferred).
• Production ML engineering excellence.
• Software development fundamentals.
• Technical leadership through influence.
• Outstanding collaboration and communication.

What Would Make You Stand Out:

• Cutting-edge AI implementation experience.
• Multi-agent and agentic systems expertise.
• MLOps and cloud-native infrastructure.
• Document and content management systems experience.
• Technical thought leadership.
• Financial services or analytical domain knowledge.
• Startup or innovation environment experience.
• Toronto AI/ML community involvement.

If you're ready to build transformative ML systems with organizational backing, cutting-edge technology, and talented colleagues—this is the moment to join us.