Senior Lead Research Scientist (Agentic AI)

TL;DR

Senior Lead Research Scientist (Agentic AI): Conduct novel research and develop production-grade tools and systems for autonomous, tool-using AI with an accent on agentic benchmarking, reinforcement learning, and alignment methods. Focus on designing rigorous evaluation protocols, building scalable experiment infrastructure, and shipping reliable AI capabilities into production.

Location: Lisbon, Portugal (onsite)

Company

Upwork Inc. is a global AI-enabled talent marketplace connecting businesses with skilled professionals across various domains, facilitating workforce transformation and innovation.

What you will do

• Split time 50/50 between novel research and engineering/productionalization of agentic AI systems.
• Define and maintain rigorous agentic benchmarking suites and evaluation protocols.
• Lead research publications and presentations on agent planning, tool use, safety, and multi-agent coordination.
• Develop reinforcement learning approaches grounded in execution feedback and design continuous learning loops.
• Build research tooling and infrastructure for large-scale agent experiments and evaluation.
• Collaborate with platform teams to transition prototypes into reliable production services and integrate with developer protocols.

Requirements

• Location: Must be based in Lisbon, Portugal (onsite).
• PhD or equivalent research experience with peer-reviewed publications in relevant AI/ML venues.
• Proven expertise in agentic evaluation, long-horizon reasoning, and LLM adaptation for tool use.
• Strong proficiency in Python and PyTorch/JAX, with experience in distributed training and experiment reproducibility.
• Experience with alignment methods (SFT, DPO, RLHF, RLAIF, RLEF) and safety testing for autonomous agents.
• Demonstrated leadership in mentoring senior researchers and leading cross-functional initiatives.

Culture & Benefits

• Opportunity to work in Upwork’s first international operational hub in Lisbon.
• Access to Upwork’s resources, culture, and growth opportunities while employed through a partner initially.
• Competitive benefits offered by the partner with potential transition to direct employment.
• Commitment to diversity, inclusion, and equitable workforce practices.