Gen AI Python Developer

Capgemini; Greater London; Hybrid; GBP 90,000 - 120,000; Full time

Job summary

Capgemini London is seeking a Gen AI Python Developer to design, build, and scale GenAI-powered data solutions for financial services. You will lead data pipelines, vector stores, retrieval systems, and LLM-driven apps for risk analytics, fraud detection, regulatory compliance, document intelligence, and customer insights.

The role blends data engineering, ML/LLM integration, and financial domain knowledge in a hybrid work model with offices, client sites, and home.

Qualifications

• Strong proficiency in Python for AI/ML development.
• Hands-on experience with ML and DL techniques.
• Expertise in PyTorch, TensorFlow, and Keras frameworks.
• Experience developing Generative AI solutions and applications.
• Strong understanding of LLMs and their architectures.
• Hands-on experience with Prompt Engineering and model optimization.
• Knowledge of LoRA/QLoRA fine-tuning.
• Experience with Hugging Face libraries and model repositories.
• Proficiency with LangChain and LlamaIndex for AI workflows.
• Experience implementing RAG frameworks.
• Knowledge of Vector Databases and Hybrid Search.
• Strong NLP concepts and applications.
• Experience with data processing, transformation, and feature engineering.
• REST API development and integration.
• Git and version control best practices.
• Experience in Agile/Scrum environments.
• Strong analytical and communication skills.
• Ability to deploy and optimize scalable AI solutions in enterprise environments.

Responsibilities

• Design, develop, and deploy AI/ML and GenAI solutions using Python.
• Build, train, evaluate, and fine-tune ML models and LLMs.
• Develop Retrieval-Augmented Generation applications using LangChain, Hugging Face, and LlamaIndex.
• Implement and optimize vector DB, semantic search, and hybrid search for AI apps.
• Model fine-tuning using LoRA and QLoRA techniques.
• Develop REST APIs and AI-driven services for enterprise integration.
• Monitor and improve model performance, scalability, reliability, and accuracy in production.
• Collaborate with stakeholders to translate requirements into AI solutions.
• Contribute to prompt engineering and AI workflow development.
• Support deployment, testing, maintenance, and continuous improvement.
• Participate in Agile/Scrum ceremonies, code reviews, documentation, and QA.

Skills

Python

Machine Learning

Deep Learning

PyTorch

TensorFlow

Keras

LLMs

Prompt Engineering

LoRA/QLoRA

Hugging Face

LangChain

LlamaIndex

RAG

Vector Databases

NLP

REST APIs

Git

Agile/Scrum

Tools

LangChain

LlamaIndex

Hugging Face

PyTorch

Job description

# Gen AI Python DeveloperLondonApply for this job* Permanent* Experienced Professionals* Data & AI* ID 549011-en\\_GB**Job Title:** **Gen AI Python Developer****Location: London****About the Job you are considering:**We are seeking a Generative AI Data Engineer with strong experience in financial services (banking, capital markets, insurance, or fintech) to design, build, and scale GenAI-powered data solutions. The role combines modern data engineering, ML/LLM integration, and domain-specific financial knowledge to deliver enterprise-grade AI platforms. You will lead the development of data pipelines, vector databases, retrieval systems, and LLM-driven applications to solve use cases such as risk analytics, fraud detection, regulatory compliance, document intelligence, and customer insights**Hybrid working:**The places that you work from day to day will vary according to your role, your needs, and those of the business; it will be a blend of Company offices, client sites, and your home; noting that you will be unable to work at home 100% of the time.**Key Responsibilities**:* Design, develop, and deploy AI/ML and Generative AI solutions using Python.* Build, train, evaluate, and fine-tune machine learning and large language models (LLMs) using frameworks such as PyTorch, TensorFlow, and Keras.* Develop Retrieval-Augmented Generation (RAG) applications using LangChain, Hugging Face, and LlamaIndex.* Implement and optimize vector database, semantic search, and hybrid search solutions for AI-powered applications.* Perform model fine-tuning using advanced techniques such as LoRA and QLoRA to improve model efficiency and performance.* Develop REST APIs and AI-driven services to enable seamless integration with enterprise applications.* Monitor, evaluate, and enhance model performance, scalability, reliability, and accuracy in production environments.* Collaborate with business stakeholders, data scientists, and engineering teams to translate requirements into effective AI solutions.* Contribute to prompt engineering, AI workflow development, and end-to-end solution implementation.* Support deployment, testing, maintenance, and continuous improvement of AI/ML applications.* Participate in Agile/Scrum ceremonies, code reviews, documentation, and quality assurance activities.* Stay updated with emerging trends and advancements in Generative AI, LLMs, and machine learning technologies, and share best practices within the team.**Required Skills*** Strong proficiency in Python programming for AI/ML application development* Hands-on experience with Machine Learning and Deep Learning techniques* Expertise in PyTorch, TensorFlow, and Keras frameworks* Experience developing Generative AI solutions and applications* Strong understanding of Large Language Models (LLMs) and their architectures* Hands-on experience with Prompt Engineering and model optimization techniques* Knowledge of Fine-Tuning methodologies, including LoRA and QLoRA* Experience working with Hugging Face libraries and model repositories* Proficiency in LangChain and LlamaIndex for building AI-powered workflows* Experience implementing Retrieval-Augmented Generation (RAG) frameworks* Knowledge of Vector Databases and Hybrid Search techniques* Strong understanding of Natural Language Processing (NLP) concepts and applications* Experience with data processing, transformation, and feature engineering* Expertise in developing and integrating REST APIs* Proficiency with Git and version control best practices* Experience working in Agile/Scrum environments and cross-functional teams* Strong analytical, problem-solving, and communication skills* Ability to design, develop, deploy, and optimize scalable AI solutions in enterprise environments**We are a Disability Confident Employer:**Capgemini is proud to be a Disability Confident Employer (Level 2) under the UK Government’s Disability Confident scheme. As part of our commitment to inclusive recruitment, we will offer an interview to all candidates who:* Declare they have a disability, and* Meet the minimum essential criteria for the role.Please opt in during the application process.**Make It Real (what does it mean for you):*** You’d be joining an accredited Great Place to work for Wellbeing in 2024. Employee wellbeing is vitally important to us as an organisation. We see a healthy and happy workforce a critical component for us to achieve our organisational ambitions. To help support wellbeing we have trained ‘Mental Health Champions’ across each of our business areas, and we have invested in wellbeing apps such as Thrive and Peppy.* You will be empowered to explore, innovate, and progress. You will benefit from Capgemini’s ‘learning for life’ mindset, meaning you will have countless training and development opportunities from thinktanks to hackathons, and access to 250,000 courses with numerous external certifications from AWS, Microsoft, Harvard Manage Mentor, Cybersecurity qualifications and much more.* You will be joining one of the World’s Most Ethical Companies, as recognised by Ethisphere for 13 consecutive years. We live our values by making ethical business choices every day. Working ethically is at the centre of our culture at Capgemini, meaning you will be helping to create a future we can all be proud of.**Why you should consider Capgemini**:Growing clients’ businesses while building a more sustainable, more inclusive future is a tough ask. When you join Capgemini, you’ll join a thriving company and become part of a collective of free-thinkers, entrepreneurs and industry experts. We find new ways technology can help us reimagine what’s possible. It’s why, together, we seek out opportunities that will transform the world’s leading businesses, and it’s how you’ll gain the experiences and connections you need to shape your future. By learning from each other every day, sharing knowledge, and always pushing yourself to do better, you’ll build the skills you want. You’ll use your skills to help our clients leverage technology to innovate and grow their business. So, it might not always be easy, but making the world a better place rarely is.**About Capgemini:**Capgemini is an AI-powered global business and technology transformation partner, delivering tangible business value. We imagine the future of organisations and make it real with AI, technology and people. With our strong heritage of nearly 60 years, we are a responsible and diverse group of 420,000 team members in more than 50 countries. We deliver end-to-end services and solutions with our deep industry expertise and strong partner ecosystem, leveraging our capabilities across strategy, technology, design, engineering and business operations. The Group reported 2024 global revenues of €22.1 billion. Make it real | www.capgemini.com