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

Citibank (Switzerland) AG; Belfast City District; Hybrid; Confidential; Full time

Benefits offered by this job

Hybrid working model

Private medical insurance

Pension plan

Paid parental leave

Job summary

Citi Belfast seeks a Senior Application Development Lead for Generative AI to drive Gen AI adoption and architecture across critical Source to Pay applications. You will design, implement, and govern end-to-end Gen AI features, balancing performance, cost, and reliability, with strong cross-team collaboration.

The role demands deep ML/DL grounding, hands-on development in Python with FastAPI, Docker, and cloud-native patterns, and a focus on responsible AI governance within agile practices.

Qualifications

• Deep expertise in Large Language Models (LLMs) and selecting right model per use case and cost.
• Hands-on experience building Gen AI apps using LangChain, LangGraph, LlamaIndex, and Hugging Face.

Responsibilities

• Set technical direction for Gen AI adoption across multiple apps or teams.
• Design, integrate, and evolve Gen AI capabilities (LLMs, APIs, agentic workflows).
• Own end-to-end delivery of Gen AI features from design to production rollout.

Skills

LLMs

LangChain

Python

FastAPI

Docker

Cloud architecture

RAG systems

PyTorch

TensorFlow

Async programming

LangGraph

LlamaIndex

Hugging Face

Tools

Docker

Job description

## Senior Application Development Lead – Generative AI (Gen AI), Vice PresidentApply: Hybrid: Belfast United Kingdom: Full time: Posted 3 Days Ago: End Date: October 2, 2026 (9 days left to apply): 26994334**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 resourcesAlongside 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.**Sounds like Citi has everything you need? Then apply to discover the true extent of your capabilities.**