Senior Application Development Lead – Generative AI (Gen AI), Vice President

Citi; Belfast City District; Hybrid; GBP 90,000 - 130,000; Full time

Benefits offered by this job

Generous holiday allowance 27 days +

Discretional bonus

Private medical insurance

Employee Assistance Program

Pension Plan

Parental Leave

Employee discounts

Learning resources

Job summary

Citi Belfast is seeking a Senior Application Development Lead – Gen AI to drive enterprise Gen AI adoption across critical applications. You will set technical direction, design robust architectures, and own end-to-end delivery of Gen AI enabled features.

Based in Belfast with a hybrid working model (up to 2 days at home per week), the role offers a competitive base salary and benefits, including generous holidays, a discretionary bonus, private medical insurance, pension, parental leave, and

Qualifications

• Deep expertise in Gen AI, LLMs, and enterprise AI adoption.
• Experience building Gen AI apps with LangChain, LangGraph, LlamaIndex.
• Hands-on with retrieval-augmented generation and vector stores.
• Proficient in Python, PyTorch or TensorFlow, and production APIs.

Responsibilities

• Set technical direction for Gen AI adoption across multiple applications or teams.
• Design, integrate, and evolve Gen AI capabilities in business-critical apps.
• Own end-to-end delivery of Gen AI features from design to production.
• Collaborate with global technology and business teams to meet regulatory and risk priorities.
• Provide technical leadership through hands-on development and code reviews.

Skills

Gen AI

LLMs

Python

FastAPI

Docker

APIs

LangChain

LangGraph

LlamaIndex

PyTorch

Tools

LangChain

LangGraph

LlamaIndex

Hugging Face

Pinecone

FAISS

pgvector

Docker

Job description

Senior Application Development Lead – Generative AI (Gen AI)

Are you looking for a career move that will put you at the heart of a global financial institution? Then bring your skills in analysis, application development, problem solving and communication to Source to Pay Solutions Technology group.

By Joining Citi, you will become part of a global organisation whose mission is to serve as a trusted partner to our clients by responsibly providing financial services that enable growth and economic progress.

Team/Role Overview

Source to Pay Solutions Technology group is part of COO (Citi Operating Office) Technology organization supporting Citi Operating Office business function and its enterprise‑wide transformation agenda to achieve improvements across risk management, controls, data governance, AI adoption, and process re‑engineering by delivering scalable, secure, and modern technology solutions. Based in Belfast, the team partners closely with businesses and technology stakeholders to build, manage, and modernize multiple Source to Pay applications, playing a key role in translating strategic transformation priorities into measurable operational outcomes.

What you’ll do

• Senior Application Development Lead (Gen AI) is a senior level position responsible for
• Set technical direction for Gen AI adoption across multiple applications or teams, defining reusable patterns, reference architectures, and best practices aligned with enterprise standards.
• Design, integrate, and evolve Gen AI capabilities (LLMs, APIs, agentic workflows, automation) in business‑critical applications, focusing on clear value, reliability, and responsible usage
• Own end‑to‑end delivery of Gen AI enabled features, from solution design and implementation through production rollout, support, and continuous improvement
• Collaborate daily with global and regional technology and business teams to deliver against regulatory, risk, and transformation priorities
• Apply agile engineering practices, leveraging iterative delivery, pragmatic architectural decisions, and emerging Gen AI/agentic tooling to accelerate outcomes
• Provide technical leadership and mentorship through hands‑on development, code reviews, and design guidance, raising the overall engineering bar
• Ensure solutions meet Citi standards for security, stability, resilience, and operational control, working closely with architecture, risk, and production support teams
• Continuously assess and improve system quality, balancing performance, cost, accuracy, and user experience in production Gen AI applications

What we’ll need from you

• Deep expertise in Large Language Models (LLMs), including commercial and open-source models ("e.g., OpenAI, Gemini, Claude, Llama"), and selecting the right model for use case, cost, and performance constraints
• Hands‑on experience building Gen AI applications using modern frameworks such as LangChain, LangGraph, LlamaIndex, and Hugging Face, including agentic and multi‑step workflows
• Proven experience designing and implementing Retrieval‑Augmented Generation (RAG) systems, including vector databases (pgvector, Pinecone, Weaviate, FAISS, etc.) and advanced retrieval strategies (hybrid search, re‑ranking, metadata filtering)
• Strong understanding of prompt engineering, workflow design, and Gen‑AI optimization, balancing latency, cost, quality, and accuracy trade‑offs in production systems
• Solid grounding in ML/DL concepts, with hands‑on experience applying frameworks such as PyTorch and/or TensorFlow, including embeddings and model fine‑tuning where appropriate
• Experience deploying and operating production Gen AI systems, leveraging Docker, cloud‑native architecture, production APIs, and monitoring/observability tools, with an emphasis on reliability and scalability
• Strong hands‑on software engineering skills, including Python, FastAPI, async programming patterns, and building high‑performance AI‑powered APIs
• Understanding of AI system evaluation, safety, and governance, including hallucination handling, guardrails, feedback loops, and responsible AI considerations, combined with the ability to work independently and communicate effectively in agile environments

What we can offer you

This role offers the opportunity to shape how Generative AI is responsibly adopted across critical enterprise workflows, influencing both technology strategy and business outcomes. You’ll work at the intersection of platform engineering, AI governance, and large‑scale transformation, with clear visibility and impact across the organization.

We work hard to have a positive financial and social impact on the communities we serve. In turn, we put our employees first and provide the best‑in‑class benefits they need to be well, live well and save well.

By joining Citi Belfast, 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:

• Generous holiday allowance starting at 27 days plus bank holidays; increasing with tenure
• A discretional annual performance related bonus
• Private medical insurance packages to suit your personal circumstances
• Employee Assistance Program
• Pension Plan
• Paid Parental Leave
• Special discounts for employees, family, and friends
• Access to an array of learning and development resources

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.

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.

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