Senior Lead Machine Learning Engineer - AI Agents

Upwork ($UPWK) is the world’s human and AI-powered work marketplace that connects businesses with highly skilled, AI-enabled independent talent from across the globe. From entrepreneurs to Fortune 100 enterprises, companies rely on Upwork’s trusted platform and its mindful AI companion, Uma, to find and hire expert talent, leverage AI-powered work solutions, and drive business transformation. With on-demand access to professionals spanning more than 10,000 skills across AI & machine learning, software development, sales & marketing, customer support, finance & accounting, and more, Upwork enables businesses of all sizes to scale, innovate, and build agile teams for the age of AI and beyond.

Upwork’s platform has facilitated more than $25 billion in economic opportunity for talent around the world. Learn more at Upwork.com and follow us on LinkedIn, Facebook, Instagram, TikTok, and X.

We’re seeking a Senior Lead AI/ML Engineer to drive the next generation of agentic intelligence through human-machine collaboration across Upwork’s platform. This is a high-impact, hands-on role at the intersection of research, platform engineering, and developer experience. You’ll lead the development of systems and protocols for AI Agents to support internal and external developers through APIs and SDKs, and serve as a thought partner in the evolution of human-machine collaboration at Upwork.

This is a unique opportunity to help define a rapidly growing domain and influence how autonomous agents are designed, built, and deployed at scale. You'll collaborate across research, engineering, product, and developer relations, ensuring agent-based systems are powerful, extensible, and developer-friendly.

• Architect and implement scalable infrastructure to support LLM-based Agentic systems, including multi-agent pipelines, and real-time orchestration.
• Design APIs, SDKs, and internal tooling to accelerate productivity through AI agent adoption.
• Drive developer advocacy by partnering to produce technical content, samples, and reference architectures that simplify integration with our platform.
• Partner with cross-functional stakeholders to align technical solutions with product strategy, ensuring high developer productivity and agent performance.
• Provide consulting and hands-on support to teams integrating with our agentic marketplace, advocating for best practices and evolving the ecosystem based on feedback.
• Contribute to AI/ML research initiatives where applicable, representing Upwork at conferences and in technical communities.

• Proven experience designing and deploying agent architectures, protocols, or LLM-powered workflows in production environments.
• Strong engineering foundation with expertise in Python and Agent frameworks (e.g., LangChain, Autogen) and protocols (e.g., MCP, A2A).
• Demonstrated success building developer platforms, APIs, SDKs, tools, or frameworks focusing on usability, extensibility, and developer support.
• Familiarity with developer relations or solutions engineering, including documentation, demos, and consultative technical work.
• You have a growth mindset, strong communication skills, and an inclusive approach to leadership. You are excited to work across functions and learn from challenges and teammates.

At Upwork, you’ll shape the future of work for a global, remote-first workforce, creating economic opportunities for professionals worldwide. While we have a physical office in Palo Alto, we currently hire full-time employees in 34 U.S. states, making it easier than ever to join our mission from wherever you call home.

Our culture is built on trust, risk-taking, customer focus, and excellence, all in service of our core mission: to create economic opportunities so people have better lives. We embrace authenticity and inclusion, encouraging everyone to bring their whole selves to work. Personal and professional growth is a priority here, supported through development programs, mentorship, and our Upwork Belonging Communities.

We’re proud to offer benefits that go beyond the basics, including comprehensive medical coverage for you and your family, unlimited PTO, a 401(k) plan with matching, 12 weeks of paid parental leave, and an Employee Stock Purchase Plan. Visit our Life at Upwork page to learn more about our values, working principles, and the overall employee experience.

Ready to help shape the future of work? Check out our Careers page to learn more about opportunities at Upwork.

Upwork is an Equal Opportunity Employer committed to recruiting and retaining a diverse and inclusive workforce. We do not discriminate based on race, religion, color, national origin, gender (including pregnancy, childbirth, or related medical conditions), sexual orientation, gender identity, gender expression, age, status as a protected veteran, status as an individual with a disability, genetic information, or other legally protected characteristics under federal, state, or local law.

Please note that a criminal background check may be required once a conditional job offer is made. Qualified applicants with arrest or conviction records will be considered in accordance with applicable law, including the California Fair Chance Act and local Fair Chance ordinances.