Lead AI/ML Engineer

Optum; Hyderabad; On-site; INR 3,500,000 - 5,500,000; Full time

Job summary

Optum is seeking a senior AI/ML expert to advance NLP and information extraction across cloud-based systems. You will lead end-to-end LLM training and deployment, leveraging transformers, knowledge graphs, and vector databases to deliver production-grade models.

You will work with cross-functional teams to translate research into scalable healthcare AI solutions, using RLHF, SFT, LoRA, and state-of-the-art tooling. Strong publication history is a plus.

Qualifications

• Master’s degree in computer science or related field.
• 12–15+ years of applied AI/ML with production experience.
• Strong NLP, ML, DL, transformer, state-space architectures.
• Strong Python, SQL, data prep and analysis.
• Experience with PyTorch.
• LLM training and fine-tuning.
• Graph-based retrieval and knowledge graphs.
• Semantic search and vector databases (FAISS/Weaviate/Milvus).
• Model fusion and ensemble techniques.
• Optimization algorithms (Bayesian, PSO, GA).
• Reinforcement learning (RLHF, PPO, DPO, GRPO), SFT, LoRA.

Responsibilities

• Lead end-to-end training and fine-tuning of LLMs across ecosystems.
• Develop ML/DL frameworks for text processing and information extraction.
• Translate research into scalable NLP cloud applications deployed at scale.
• Architect and implement GraphRAG pipelines and knowledge graphs.
• Design embeddings for document understanding and retrieval.
• Build semantic retrieval with advanced segmentation and indexing.
• Scale distributed training environments with NCCL and InfiniBand.
• Apply RL techniques to align model behavior with goals.
• Collaborate with cross-functional teams to deploy AI solutions in production.

Skills

Python

PyTorch

NLP

Deep learning

Transformer models

Knowledge graphs

Semantic search

Vector embeddings

Reinforcement learning

Distributed training

Education

Master’s degree in computer science or related field

Tools

FAISS

Weaviate

Milvus

NCCL

DeepSpeed

Horovod

Job description

Primary responsibilities include the enhancement of existing company NLP technologies and extension of those systems in new cloud-based applications. Emphasis is on development of novel machine/deep learning techniques for information extraction and synthesis. They translate research code into clinical NLP solutions deployed at scale in production environments including statistical methods, deep learning, and large language model technologies. Work will involve all aspects of methods development from initial PoC implementation to performance characterization and production launch of new methods.

The successful candidate will have a strong history of publication in Machine/Deep Learning with an emphasis on Natural Language Processing, Information Retrieval and/or Information Extraction. Exposure to recent research literature and the ability to effectively implement new technologies is key. The successful candidate will have proven success in taking machine/deep learning solutions to production environments. Strong technical skills are required.

Key Responsibilities

• Lead end-to-end training and fine-tuning of Large Language Models (LLMs), including both open-source (e.g., Qwen, LLaMA, Mistral) and closed-source (e.g., OpenAI, Gemini, Anthropic) ecosystems.
• Deep knowledge and extensive experience with Machine/Deep Learning frameworks including transformer architectures, state space models, large language models, and agentic approaches
• Knowledge of algorithms and techniques within a computational domain with emphasis on text processing
• Demonstrated publication record in AI domain especially relating to text extraction and summarization
• Architect and implement GraphRAG pipelines, including knowledge graph representation and retrieval for enhanced contextual grounding.
• Design, train, and optimize semantic and dense vector embeddings for document understanding, search, and retrieval.
• Develop semantic retrieval systems with advanced document segmentation and indexing strategies.
• Build and scale distributed training environments using NCCL and InfiniBand for multi-GPU and multi-node training.
• Apply reinforcement learning techniques (e.g., RLHF, RLAIF) to align model behavior with human preferences and domain-specific goals.
• Experience with Hybrid NLP solutions that combine symbolic and machine learning approaches
• Collaborate with cross-functional teams to translate business needs into AI-driven solutions and deploy them in production environments.

Required Qualifications

Master’s degree in computer science, Machine Learning, or related field.

12-15+ years of experience in applied AI/ML with statistics, with a strong track record of delivering production-grade models.

Deep expertise in: NLP, Fundamental machine learning, deep learning, transformer, state space-based architecture

Strong in Python coding, SQL and database queries, data preparation, and analysis

Exploratory Data Analysis (EDA)

Experience with PyTorch

LLM training and fine-tuning (e.g., GPT, LLaMA, Mistral, Qwen)

Graph-based retrieval systems (knowledge graphs)

Semantic search and vector databases (e.g., FAISS, Weaviate, Milvus)

Model fusion and ensemble techniques (stacking, boosting, gating)

Optimization algorithms (Bayesian, Particle Swarm, Genetic Algorithms)

Reinforcement learning (e.g., RLHF, PPO, DPO, GRPO), Supervised Fine Tuning (SFT), LoRA, QLoRA, axolotl

Bonus Skills

• Experience with healthcare data and medical coding systems (e.g., CPT, CM, PCS).
• Familiarity with regulatory and compliance frameworks in AI deployment.
• Contributions to open-source AI projects or published research. And/Or ability to take research papers to poc – production.
• Document segmentation and preprocessing (OCR, layout parsing)
• Distributed training frameworks (NCCL, Horovod, DeepSpeed)
• High-performance networking (InfiniBand, RDMA)
• Symbolic AI and rule-based systems
• Meta-learning and Mixture of Experts architectures