Lead AI/ML Engineer - AI Agents

Summary

Join Upwork as a Lead AI/ML Engineer and design cutting-edge infrastructure and models for agentic LLM workflows. You will work at the intersection of research and production, delivering advanced ML solutions and driving business outcomes. This role offers leadership opportunities on high-impact projects, mentoring others, and shaping the future of autonomous AI agents. You will contribute to the broader AI research community through publications. Upwork provides a remote-first work environment with benefits including comprehensive medical coverage, unlimited PTO, a 401(k) plan with matching, 12 weeks of paid parental leave, and an Employee Stock Purchase Plan.

Requirements

• Strong proficiency in Python and modern ML frameworks such as PyTorch or TensorFlow, with experience developing and deploying AI systems
• Deep understanding of core ML concepts, including transformers, generative models, and agent architectures such as MCP or A2A
• Experience training large models on GPU clusters and integrating LLMs with external tools via APIs or orchestration frameworks
• Comprehensive understanding of foundational deep learning, machine learning concepts, and state-of-the-art GenAI models
• Hands-on experience training custom LLMs on GPUs and working with Retrieval-Augmented Generation (RAG) systems
• Proven ability to build end-to-end ML pipelines—from data prep and experimentation to production deployment—in a cloud-native environment
• A growth mindset, strong communication skills, and the ability to translate complex technical work to stakeholders across functions

Responsibilities

• Architect and implement core infrastructure to support agent-based LLM systems, including multi-agent pipelines, RAG, and real-time orchestration
• Train and fine-tune custom models, including LLMs and foundation models, to solve unique Upwork-specific challenges
• Lead cross-functional collaboration across engineering, product, and research teams to align technical solutions with business impact
• Mentor and guide engineers and researchers, helping foster a high-performing, inclusive team culture grounded in AI excellence
• Translate experimental ideas into reliable, scalable production systems by applying best practices in AI engineering and deployment
• Publish and share innovations where appropriate, contributing to Upwork’s visibility in the broader AI/ML research community

Preferred Qualifications

Demonstrated experience working in R&D environments; publications in major AI/ML conferences are a plus, but not required

Benefits

• Comprehensive medical coverage for you and your family
• Unlimited PTO
• A 401(k) plan with matching
• 12 weeks of paid parental leave
• An Employee Stock Purchase Plan