Senior Lead Python AI/ML Engineer

Job description

Role Overview

We are seeking an experienced and visionary Senior Lead Python AI/ML Engineer with Generative AI Capabilities to lead the design, development, and deployment of next-generation artificial intelligence and machine learning solutions based out of our Chennai center (operating in a Hybrid work model). With 10 to 12 years of hands-on software and machine learning engineering experience , the ideal candidate will drive the convergence of traditional predictive ML models and modern Foundation Model / GenAI architectures.

In this role, you will be instrumental in building high-scale, low-latency AI solutions applied to Fraud Mitigation, Risk Scoring, and Loss Prevention across US Retail Banking products 2.

Key Responsibilities

AI/ML & Generative AI Architecture Architect, build, and deploy production-grade Generative AI systems, including Retrieval-Augmented Generation (RAG) , autonomous agents, semantic search pipelines, and multi-modal AI workflows. Integrate state-of-the-art Large Language Models (LLMs)—including Google Gemini , Anthropic Claude , and open-source models (Llama, Mistral)—optimizing for latency, cost, and accuracy. Build domain-specific prompt engineering frameworks, fine-tuning pipelines (LoRA/QLoRA), model evaluation benchmarks, and guardrails to minimize hallucinations and bias.

Lead the architecture of predictive ML algorithms (anomaly detection, graph neural networks, supervised/unsupervised classifiers) tailored to real-time risk assessment. Software Engineering & System Scalability Design resilient, low-latency, and horizontally scalable microservices and APIs in Python (FastAPI, Flask, AsyncIO) handling high-throughput transactional traffic. Integrate vector databases (e.g., Pinecone, Milvus, Qdrant, Chroma, pgvector) with distributed caching and event streaming platforms (Kafka, RabbitMQ).

Implement robust MLOps and LLMOps practices (CI/CD pipelines, automated model retraining, observability with MLflow/Weights & Biases, model drift monitoring). Fraud Analytics & Domain Innovation Collaborate closely with US-based and global Risk, Compliance, and Loss Prevention teams to build AI solutions targeting identity theft, account takeover (ATO), synthetic identity fraud, card-not-present (CNP) fraud, and transaction anomaly detection.

Utilize unstructured data (investigator notes, SAR filings, customer interaction logs) via GenAI to automate fraud triage and investigative summarization. Ensure strict adherence to US Banking regulatory standards (FCRA, GLBA, Model Risk Management SR 11-7, Fair Lending, Explainable AI / XAI). Technical Leadership & Mentorship Mentor senior/mid-level data scientists and software engineers across the Chennai engineering hub in modern GenAI patterns, clean code principles, and production readiness.

Drive technical roadmap, evaluate emerging AI frameworks, conduct proof-of-concepts (PoCs), and present architectural proposals to global engineering leadership. 3.

Required Qualifications & Experience

Education: Bachelor’s or Master’s degree in Computer Science, Data Science, Artificial Intelligence, Applied Mathematics, or a related quantitative field.

Total Experience

10 to 12 years of professional experience in software engineering and production AI/ML system development.

Core Python Expertise

Advanced proficiency in Python 3.x (multiprocessing/asyncio, design patterns, profiling, packaging, and clean code paradigms).

Core ML Frameworks

Deep practical experience with PyTorch, TensorFlow, Scikit-learn, XGBoost, and LightGBM.

Generative AI Proficiency

Demonstrated success building production GenAI applications (LangChain, LlamaIndex, CrewAI, AutoGen). Hands-on experience with embedding models, dense retrieval, rerankers, and vector indexing strategies.

Distributed Systems & Cloud

Strong hands-on experience with cloud platforms (AWS, GCP, or Azure), containerization (Docker, Kubernetes), and distributed data processing (PySpark, Ray).

MLOps / LLMOps

Proven track record in orchestrating end-to-end ML lifecycles from data validation to real-time inference monitoring. 4. Preferred & Good-to-Have Skills Google Gemini & Anthropic Claude: Hands-on experience with API integration, function calling/tools, context caching, and prompt optimization specifically for Google Gemini (Pro/Flash) and Anthropic Claude (Opus/Sonnet/Haiku).

Domain Knowledge (Fraud & Loss Prevention)

Experience designing fraud rule engines, anomaly detection platforms, or predictive risk models. Familiarity with transaction monitoring, biometric behavioral analytics, and fraud consortium datasets. 5.

Technical Skills

Matrix Category Technologies & Tools Programming Languages Python (Advanced), SQL, Bash Generative AI & LLMs Anthropic Claude, Google Gemini, OpenAI GPT, Open-source LLMs (Llama, Mistral), LangChain, LlamaIndex, DSPy Classical & Deep ML PyTorch, TensorFlow, Scikit-Learn, XGBoost, LightGBM, Hugging Face Transformers Vector DBs & Search Pinecone, Milvus, Qdrant, Weaviate, FAISS, pgvector, Elasticsearch Backend & APIs FastAPI, Flask, AsyncIO, gRPC, REST Data & Streaming Apache Kafka, Apache Spark / PySpark, Pandas, Polars, DuckDB MLOps & DevOps MLflow, Kubeflow, Docker, Kubernetes, GitHub Actions, Terraform, Prometheus/Grafana Domain Tools & Standards Model Risk Management (SR 11-7), Explainable AI (SHAP, LIME), PII Masking 6.

Key Performance Indicators (KPIs) Model Performance & Accuracy

Precision/Recall trade-offs in fraud detection, false positive reduction, and sub-100ms real-time inference latency.

Engineering Excellence

Code quality, test coverage (>85%), modular design, and robust error handling.

Business Impact

Measurable reduction in fraud loss basis points and acceleration of investigator workflow efficiency through GenAI summarization/triage.

Mentorship & Global Delivery

On-time milestone delivery, technical capability elevation across local and global engineering pods. ------------------------------------------------------ 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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