AI Software Engineer in London

hackajob is collaborating with Moody's Corporation to connect them with exceptional professionals for this role. At Moody's, we unite the brightest minds to turn today’s risks into tomorrow’s opportunities. We do this by striving to create an inclusive environment where everyone feels welcome to be who they are—with the freedom to exchange ideas, think innovatively, and listen to each other and customers in meaningful ways. Moody’s is transforming how the world sees risk. As a global leader in ratings and integrated risk assessment, we’re advancing AI to move from insight to action—enabling intelligence that not only understands complexity but responds to it. We decode risk to unlock opportunity, helping our clients navigate uncertainty with clarity, speed, and confidence.

If you are excited about this opportunity but do not meet every single requirement, please apply! You still may be a great fit for this role or other open roles. We are seeking candidates who model our values: invest in every relationship, lead with curiosity, champion diverse perspectives, turn inputs into actions, and uphold trust through integrity.

• 3+ years of experience in backend software development with a focus on Node.js, building scalable and production‑grade systems
• Hands‑on experience with AI applications, including LLM implementations, retrieval‑augmented generation, prompt optimization, and fine‑tuning methodologies
• Proven ability to optimize systems for latency, cost, and reliability, and to take AI agents from research to production
• Strong knowledge of cloud platforms (e.g., AWS, GCP, Azure), containerization technologies (e.g., Docker, ECS, Kubernetes), and MLOps practices
• Proficiency in databases (e.g., PostgreSQL, MongoDB) and caching systems (e.g., Redis, Memcached) for scalable data storage and retrieval
• Familiarity with Python for collaborating on machine learning workflows and integrating Python‑based AI tools is preferred
• Excellent problem‑solving skills, with the ability to navigate ambiguity and deliver impactful solutions aligned with business goals
• Effective communication and collaboration skills, with demonstrated experience working across cross‑functional teams

• Bachelor’s degree or higher in Computer Science, Software Engineering, or a related field.

• As a Software Engineer specializing in AI systems, you will play a key role in designing and implementing production‑grade software solutions that leverage cutting‑edge machine learning techniques, including large language models (LLMs), natural language processing systems (NLP), and AI agents.
• Your primary focus will be building scalable, efficient, and maintainable backend systems using Node.js & Python, while also integrating machine learning workflows and AI‑driven applications.
• You will work closely with data scientists, machine learning engineers, and other stakeholders to develop robust platforms capable of supporting advanced AI capabilities.
• Design and implement AI‑driven backend systems using Node.js, creating APIs and services to support applications such as NLP, search, recommendation systems, and AI agents.
• Build and integrate large language model (LLM) applications and AI agents using techniques such as retrieval‑augmented generation, prompt optimization, fine‑tuning, and reinforcement learning.
• Develop end‑to‑end pipelines for data ingestion, feature engineering, model inference (batch and real‑time), and integration of AI‑driven workflows into production systems.
• Collaborate with data scientists and machine learning engineers to ensure seamless integration of machine learning practices in Gen AI.
• Optimize backend systems for latency, scalability, and cost, applying caching, load balancing, and other performance techniques to support high‑volume inference workloads.
• Advocate for and implement MLOps best practices, including monitoring, logging, tracing, automated retraining, and model/prompt versioning to ensure robust and reliable AI systems.
• Build reusable platforms or frameworks that streamline the deployment and monitoring of AI agents and machine learning models.
• Lead the implementation of autonomous agents capable of multi‑step reasoning, decision‑making, and tool use in production environments.
• Participate in design reviews, write high‑quality code, and contribute to documentation to ensure team‑wide efficiency and maintainability.
• Mentor junior engineers and collaborate across disciplines to drive impactful solutions while aligning system design with business outcomes.

Our Innovation team is responsible for building internal and external solutions leveraging cutting‑edge machine learning technology, including LLMs, AI Agents and NLP. The group is made up of a diverse set of professionals spanning a wide range of experience levels. We’re organized into agile squads, each focused on building and scaling innovative AI‑driven products that enhance productivity and deliver measurable value. Collaboration is a cornerstone of how we operate. Engineers and data scientists work closely together to experiment, iterate, and deploy solutions in a fast‑paced environment. Joining our team means contributing to an open and supportive culture where learning and knowledge‑sharing are encouraged, and where every team member has the opportunity to make a tangible impact.

Moody’s is an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, national origin, disability, protected veteran status, sexual orientation, gender expression, gender identity or any other characteristic protected by law.

Candidates for Moody’s Corporation may be asked to disclose securities holdings pursuant to Moody’s Policy for Securities Trading and the requirements of the position. Employment is contingent upon compliance with the Policy, including remediation of positions in those holdings as necessary.