Job Description

About Citi Innovation Labs:
Citi Innovation Labs is a global network of innovation centres delivering cutting-edge technological solutions across Citi's lines of business. Our Labs Network spans New York, London, Tel Aviv, Dublin and other global locations focusing on research and implementation in AI, machine learning, NLP, analytics, blockchain, and distributed ledger technology. We partner closely with business stakeholders to drive innovation from ideation to production, creating competitive advantage through technological excellence.
The role:
You'll be a senior individual contributor and hands-on tech lead who designs, builds, and ships GenAI-powered products and platforms. You'll own problem framing with business sponsors, architect robust retrieval and orchestration, define evaluation and safety bars, and guide product engineers/data scientists to production outcomes.
What you'll do:

• Productise GenAI: Deliver LLM-powered workflows for internal users and clients using hosted or private models.
• Build Agentic Systems: Design autonomous agents with reasoning, planning, and tool-use capabilities; implement multi-agent coordination for complex workflows; embed guardrails and deterministic fallbacks.
• Architect advanced RAG pipelines: Deploy hybrid retrieval strategies, incorporating semantic search, query routing, contextual compression, and re-ranking; optimize for accuracy, latency, and cost; ensure auditability with proper citations and provenance tracking.
• Establish evaluation frameworks: Define comprehensive assessment methodologies covering contextual relevance, hallucination detection, and grounding. Produce model-risk documentation aligned to Citi standards.
• Set technical standards: Create reusable patterns for prompt engineering, orchestration, and model selection; establish best practices for GenAI-powered application development; influence architecture decisions across Innovation Labs.
• Lead stakeholder collaborations: Translate business requirements into technical roadmaps. Effectively communicate with senior stakeholders and cross-functional partners;
• Provide technical mentorship: Provide technical guidance to data scientists and product engineers on model selection, evaluation design and production best-practices; elevate team capabilities through code/architecture reviews and knowledge-sharing
• Continually evolve: Stay at the forefront of AI advancements and industry best practices, driving a culture of continuous improvement and innovation within our systems.

What we're looking for:

• Applied Machine Learning Acumen: Strength in model capabilities/limits, prompting patterns, function/tool-calling, embeddings selection, and vector semantics (ANN indexes, HNSW/IVF, hybrid search, rerankers) .
• Agentic AI Design: Proven experience building multi-tool, multi-step agents with deterministic fallbacks, safety checkpoints, and recovery strategies.
• Advanced RAG Expertise: Hands-on expertise with semantic chunking, query decomposition, hybrid search, metadata filtering, and reranking; understanding of retrieval optimization and result synthesis strategies.
• Evaluation methodologies: Experience designing robust evaluation frameworks (both manual and automated) including golden sets, reference-free evals, benchmark testing, and online metrics.
• Software Engineering Toolkit: A commitment to best practices, utilizing design patterns to architect scalable, maintainable solutions, and a history of leading impactful code reviews that elevate team quality.
• Expert Python Craftmanship: Deep expertise in Python, evidenced by building high-performance applications, developing bespoke modules, and seamlessly integrating Python with diverse systems using advanced features and libraries.
• Stakeholder Communication: Ability to articulate complex technical concepts to both technical and non-technical audiences; comfortable presenting to senior leadership; skilled at translating business needs into technical solutions.

Nice to have:

• Experience working with multimodal data (text, images, and documents)
• Fine-tuning knowledge (LoRA, QLoRA, PEFT) and understanding of when to fine-tune versus retrieve or prompt-engineer
• Document processing expertise for PDFs, tables, and structured data extraction
• Knowledge graphs or entity store for enhanced grounding and retrieval
• Structured tool integration (SQLs/APIs) for complex task execution
• Familiarity with AI governance and policy enforcement mechanisms
• Proficiency leveraging coding agents (GitHub Copilot, Claude Code, Devin) to accelerate development velocity and code quality
• Background in financial services industry beneficial, but not required

What we'll provide you
This is a unique role that will put you in the position to be part of a new venture and actively drive change. Every day there will be new challenges that will help you develop new skills that can drive your career.
By joining Citi London, you will not only be part of a business casual workplace with a hybrid working model (up to 2 days working at home per week), but also receive a competitive base salary (which is annually reviewed), and enjoy a whole host of additional benefits such as:

• 27 days annual leave (plus bank holidays)
• A discretional annual performance related bonus
• Private Medical Care & Life Insurance
• Employee Assistance Program
• Pension Plan
• Paid Parental Leave
• Special discounts for employees, family, and friends

Alongside these benefits Citi is committed to ensuring our workplace is where everyone feels comfortable coming to work as their whole self, every day. We want the best talent around the world to be energized to join us, motivated to stay and empowered to thrive.
#LI-RH4
Job Family Group: Technology
Job Family: Applications Development
Time Type: Full time
Most Relevant Skills Please see the requirements listed above.
Other Relevant Skills For complementary skills, please see above and/or contact the recruiter.
Citi is an equal opportunity employer, and qualified candidates will receive consideration without regard to their race, color, religion, sex, sexual orientation, gender identity, national origin, disability, status as a protected veteran, or any other characteristic protected by law.
If you are a person with a disability and need a reasonable accommodation to use our search tools and/or apply for a career opportunity review .
View Citi's and the poster.

Skills Required