Senior Software Engineer (Java or Python)

Salary: £62,000 - 102,000 per year

Requirements:

• Experience in full-stack application development with strong expertise in Java or Python
• Deep experience with backend frameworks such as Spring Boot, Spring Core, Flask, or FastAPI
• Solid frontend experience with modern JavaScript frameworks such as React, Angular, or Vue
• Experience designing and delivering scalable, cloud-native applications
• Exposure to Gen-AI concepts, including large language models, transformer-based systems, prompt engineering, basic agent workflows, and vector search or retrieval concepts
• Familiarity with Gen-AI frameworks and tools such as LangChain, LangGraph, MLflow, or workflow orchestration tools such as n8n; hands-on experience is preferred, but deep ML expertise is not mandatory
• Experience integrating Gen-AI APIs such as OpenAI, Gemini, or Claude into production applications
• Familiarity with at least one major cloud provider such as AWS, GCP, or Azure

Responsibilities:

• Partner with multiple management teams to ensure appropriate integration of functions to meet goals and identify and define necessary system enhancements to deploy new products and process improvements
• Resolve a variety of high-impact problems and projects through in-depth evaluation of complex business processes, system processes, and industry standards
• Provide expertise in applications programming and ensure application design adheres to the overall architecture blueprint
• Utilize advanced knowledge of system flow and develop standards for coding, testing, debugging, and implementation
• Develop comprehensive knowledge of how areas of business, such as architecture and infrastructure, integrate to accomplish business goals
• Provide in-depth analysis with interpretive thinking to define issues and develop innovative solutions
• Serve as advisor or coach to mid-level developers and analysts, allocating work as necessary
• Assess risk appropriately when business decisions are made, with consideration for the firms reputation and safeguarding Citigroup, its clients, and assets by driving compliance, applying sound ethical judgment, and escalating, managing, and reporting control issues with transparency

Technologies:

• AI
• AWS
• Angular
• Backend
• Cloud
• FastAPI
• Flask
• Flow
• Frontend
• GCP
• Java
• JavaScript
• MLflow
• n8n
• Network
• Python
• React
• Spring
• Spring Boot
• Vue
• Azure
• Support

More:

We are Citi, and our Tech team is helping to redefine global finance at scale, with $5 trillion moving through our network every day and operations across 180+ countries. We offer a business casual workplace with a hybrid working model of up to 2 days working from home per week, along with a competitive base salary reviewed annually and benefits including 27 days annual leave plus bank holidays, a discretionary annual performance-related bonus, private medical care and life insurance, an employee assistance program, a pension plan, paid parental leave, special discounts for employees, family, and friends, and access to learning and development resources. We are committed to helping our people grow through mentorship, continuous learning, flexibility, and an inclusive environment where everyone can feel comfortable bringing their whole self to work. This role is based in Belfast, Northern Ireland, United Kingdom.

last updated 34 week of 2026