About Us
Built by People Who've Been in the Trenches
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Proin lacinia nisl at sapien dignissim, vel tincidunt magna bibendum.
Robert Samuel
Co-Founder
For nearly four decades, Robert Samuel has worked at the center of how complex institutions operate—first as a senior trader and quantitative practitioner in global capital markets, then as a leader who builds the systems and processes those markets depend on. Plumbline is the distillation of that experience. Robert co-founded the company, developed its underlying mathematics, and wrote the software that turns business-process analysis from an art into a formal method.
Robert's authority on process is earned at the highest level of the market. He spent the core of his career on the trading floor—ultimately as a head trader with global responsibility for new and exotic OTC interest-rate derivatives—structuring, pricing, and risk-managing some of the most complex instruments in finance and bringing new products to market across sales, risk, technology, and operations. Over the decades he has held senior roles at the world's leading financial institutions, consistently where trading strategy, quantitative modeling, and operational reality meet.
His leadership reaches well beyond the desk. He has built and run large, geographically distributed organizations and delivered complex software platforms end to end—in one case leading a multi-city operation whose product lifted its owners to a higher-than-anticipated exit. More recently he has worked at the frontier of AI and capital markets, bringing the same instinct for turning complexity into something structured and provable that now defines Plumbline.
Jonathan Kastin
Co-Founder
Jonathan Kastin has 20 years of experience in financial technology (UBS, JPMorgan Chase, etc), after a prior career as a philosophy professor. His work centers on understanding real business needs, and matching those with the best technical solutions.
Jonathan has worked extensively in market risk and credit risk, especially for fixed income securities and derivatives. He has led teams building out data, analytics, reporting, and most recently LLM-generated text, to support portfolio managers, risk managers, and financial regulators.
Jonathan received his undergraduate degree from Harvard University, and his graduate degree from the City University of New York Graduate Center. He lives with his wife and 3 children in New York.