Description

Legend Biotech is seeking an Associate, AI/ML Engineer as part of the IT team based in Somerset, NJ.

Role Overview

We are seeking a motivated and curious Associate AI/ML Engineer to join our Data & AI team. In this role, you will help design, build, test, and deploy production-grade Generative AI solutions-leveraging large language models (LLMs), retrieval-augmented generation (RAG), and agentic workflows-along with traditional machine learning models that support business and product goals. This is an excellent opportunity for early-career professionals to gain hands-on experience in building safe, reliable AI applications in real-world environments.

Key Responsibilities

• Build and iterate on LLM-powered features (e.g., chat, summarization, extraction, classification) using approved model providers and internal platforms.
• Design retrieval-augmented generation (RAG) solutions, including document ingestion, chunking, embeddings, vector search, and prompt templates.
• Develop and evaluate prompts, tools, and agentic workflows; implement guardrails (grounding, citations, refusal behavior) and improve reliability.
• Create offline and online evaluation for GenAI systems (test sets, automated metrics, human review processes) and track quality over time.
• Assist with developing, training, and evaluating traditional ML models when needed (e.g., classification, regression, anomaly detection, recommendation).
• Clean, preprocess, and analyze structured and unstructured data; build reproducible data pipelines for model inputs and evaluation.
• Collaborate with data scientists, software engineers, security, and product teams to translate business requirements into safe, scalable solutions.
• Support deployment, monitoring, and cost/performance optimization for GenAI services (latency, token usage, caching, drift, incident response).
• Write clean, maintainable, and well-documented code; contribute to code reviews, runbooks, and user documentation.
• Works under guidance to make day-to-day technical decisions such as selecting baseline prompts/RAG patterns, defining evaluation criteria (quality, safety, latency, cost), and proposing experiment plans.
• Escalates architecture, production rollout, security, and data governance decisions to senior engineers/tech lead; contributes input through code reviews, documentation, and demos.

Requirements

• Bachelor's degree in Computer Science, Data Science, Engineering, Mathematics, or a related field (or equivalent practical experience).
• Internship, academic project, or capstone experience building GenAI/LLM or ML applications.
• Hands-on experience with at least one LLM framework/tooling (e.g., LangChain, LlamaIndex, Semantic Kernel) or equivalent custom orchestration.
• Exposure to RAG building blocks (document ingestion, chunking, embeddings, vector databases/search).
• Familiarity with evaluation approaches for LLM systems (golden sets, qualitative rubrics, automated checks) and basic experiment tracking.
• Familiarity with SQL and relational databases; experience working with unstructured text data is a plus.
• Basic knowledge of cloud platforms (AWS, Azure, or GCP) and deploying services via APIs.
• Experience with version control tools (Git/GitHub) and collaborative development workflows.
• IT Skills: Python; Jupyter/VS Code; Git; Linux fundamentals; Docker basics; REST APIs; SQL; basic CI/CD concepts; familiarity with LLM APIs and orchestration frameworks (e.g., LangChain/LlamaIndex/Semantic Kernel); embeddings and vector databases/search (e.g., Pinecone/FAISS/Azure AI Search or equivalent); experiment tracking/evaluation tooling (e.g., MLflow or equivalent); basic monitoring/observability concepts (logs, traces, latency, token usage).

#Li-BG1

#Li-Hybrid

Legend Biotech is a global biotechnology company dedicated to treating, and one day curing, life-threatening diseases. Headquartered in Somerset, New Jersey, we are developing advanced cell therapies across a diverse array of technology platforms, including autologous and allogenic chimeric antigen receptor T-cell, T-cell receptor (TCR-T), and natural killer (NK) cell-based immunotherapy. From our three R&D sites around the world, we apply these innovative technologies to pursue the discovery of safe, efficacious and cutting-edge therapeutics for patients worldwide.

Legend Biotech entered into a global collaboration agreement with Janssen, one of the pharmaceutical companies of Johnson & Johnson, to jointly develop and commercialize ciltacabtagene autolecuel (cilta-cel). Our strategic partnership is designed to combine the strengths and expertise of both companies to advance the promise of an immunotherapy in the treatment of multiple myeloma.

Please note: These benefits are offered exclusively to permanent full-time employees. Contractors are not eligible for benefits through Legend Biotech.

EEO Statement

It is the policy of Legend Biotech to provide equal employment opportunities without regard to actual or perceived race, color, creed, religion, national origin, ancestry, citizenship status, age, sex or gender (including pregnancy, childbirth, related medical conditions and lactation), gender identity or gender expression (including transgender status), sexual orientation, marital status, military service and veteran status, disability, genetic information, or any other protected characteristic under applicable federal, state or local laws or ordinances.

Employment is at-will and may be terminated at any time with or without cause or notice by the employee or the company.

For information related to our privacy notice, please review: Legend Biotech Privacy Notice .