Upwork · 3 months ago
Senior Lead Machine Learning Engineer
United States
Full-time
Remote
Senior Level, Lead/Staff
$195K/yr - $296K/yrUpwork is the world’s human and AI-powered work marketplace that connects businesses with highly skilled, AI-enabled independent talent from across the globe. We’re seeking a Senior Lead Machine Learning Engineer to play a pivotal role in shaping the future of AI-powered intelligence at Upwork, leading the design and delivery of infrastructure and models that support agentic LLM workflows across our platform.
FreelanceMarketplacePeer to PeerRecruiting
Responsibilities
Design and implement resilient infrastructure for agentic LLM systems, including multi-agent coordination, Retrieval-Augmented Generation (RAG), and real-time orchestration
Lead training and fine-tuning of large-scale foundation models tailored to Upwork’s domain-specific challenges and user base
Partner with engineering, product, and research teams to align technical development with strategic business priorities
Mentor and support other engineers and researchers to elevate team-wide technical capabilities and foster a culture of innovation and inclusion
Drive experimentation and translate findings into robust, scalable production systems with clear metrics of success
Identify opportunities for innovation, challenge conventional approaches, and lead initiatives that push the boundaries of applied ML
Contribute to the external AI/ML community through papers, talks, or open-source contributions, enhancing Upwork’s visibility in the field
Qualification
Required
Demonstrated expertise in building, deploying, and scaling advanced ML models in a production environment using Python and frameworks like PyTorch or TensorFlow
Deep technical understanding of transformer-based models, generative AI, and agent architectures such as MCP or A2A
Proven experience training and optimizing large models on GPU clusters and integrating LLMs with APIs or orchestration systems
Track record of leading high-impact, cross-functional initiatives with a focus on business outcomes and customer value
A collaborative mindset, clear communication skills, and a drive to mentor and elevate those around you
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
Company
Upwork
Upwork is an online marketplace that connects corporate businesses and organizations with field professionals and independent talents.
Founded in 2014
501-1000 employees
H1B Sponsorship
Upwork has a track record of offering H1B sponsorships. Please note that this does not
guarantee sponsorship for this specific role. Below presents additional info for your
reference. (Data Powered by US Department of Labor)
Distribution of Different Job Fields Receiving Sponsorship
Represents job field similar to this job
Trends of Total Sponsorships
2025 (16)
2024 (28)
2023 (23)
2022 (35)
2021 (29)
2020 (22)
Funding
Current Stage
Public CompanyTotal Funding
$168.8MKey Investors
BenchmarkDAG VenturesSigma Partners
2018-10-02IPO
2017-01-01Series Unknown
2016-10-27Secondary Market
Leadership Team
Hayden Brown
President and Chief Executive Officer
Erica Gessert
Chief Financial Officer
Recent News
2026-01-09
2025-12-11
Company data provided by crunchbase