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Leadership

Maria Siambekos

Maria Siambekos

President and Chief Operating Officer

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Maria Siambekos

Maria Siambekos

President and Chief Operating Officer

Maria Siambekos is a healthcare technology executive with more than 25 years of diverse business experience in Fortune 10 and VC/PE backed organizations. She has served as CEO, President, and COO of multiple growth stage Healthcare IT enterprise SaaS-based companies resulting in multiple successful exits. She has also held numerous leadership roles at GE Healthcare and Hospira in commercial, product, strategy, business integration, and M&A.

Maria began her career as a clinical scientist at The University of Chicago and as a consultant, where she delivered a breadth of strategic, operational, and clinical technology consulting engagements for hospitals, health systems, and payers. Maria has a B.S. in Biology from Yale University and an MBA from The University of Chicago Booth School of Business.

John Starr

John Starr

Chief Financial Officer

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John Starr

John Starr

Chief Financial Officer

John is a growth-equity financial leader with over 25 years of experience in all facets of financial management at companies ranging from large publicly traded enterprises to private equity and venture-backed investments. Prior to Cayuse, John was CFO of Forte Research Systems, a market leader in clinical trial management software, and Emmi Solutions, a leading patient engagement technology platform.

As CFO, John led both companies through exponential business growth, culminating in successful acquisitions by strategic investors. John has also previously held leadership positions at Orius Corp and AT&T. He began his finance career at Deloitte in their audit and advisory services practice.

John received a B.S. in public affairs from Indiana University, Bloomington, and a masters degree in accountancy from DePaul University.

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Barbara Timbers-Purcell

SVP Engineering

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Barbara Timbers-Purcell

SVP Engineering

Barbara (Barb) brings more than 25 years of technology leadership experience across a range of industries including supply chain, health insurance, utilities, pharmaceuticals, and professional services. She specializes in scaling engineering teams, modernizing cloud-based platforms, and building the processes and culture that enable high-performing organizations to deliver with consistency and speed.

Most recently, Barb served as SVP of Technology at Interos, where she led an engineering organization building a supply chain risk management SaaS platform. Prior to that, she served as General Manager at Neudesic, overseeing a technical consulting practice serving the Phoenix region, and as VP of Technology at Genius Avenue, where she built and transformed the company’s IT function from the ground up.

Barb holds an Engineering from the University of Illinois and an MBA from the W. P. Carey School of Business at Arizona State University.

Shannon Prillaman

Shannon Prillaman

VP of People Operations

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Shannon Prillaman

Shannon Prillaman

VP of People Operations

Shannon brings over 20 years of human resources leadership experience across Fortune 500 and high-growth technology organizations. As Vice President of People Operations at Cayuse, she leads global people strategy, talent development, and organizational effectiveness initiatives that align with business goals and foster a culture of accountability and growth.

She began her career in recruitment before moving into labor relations, developing expertise in employee engagement, workforce development, and leadership coaching. Her experience spans large enterprises and venture-backed startups. Shannon holds a B.A. in Business and Organizational Leadership from the University of South Florida and is passionate about building high-performing teams and creating inclusive, purpose-driven workplaces where people and business success thrive together.

DJ Thakkar

DJ Thakkar

SVP of Product Management

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DJ Thakkar

DJ Thakkar

SVP of Product Management

DJ Thakkar brings over 20 years of B2B SaaS product management and consulting experience across a number of industry verticals including HR Tech, Advertising, Legal, Financial Services and CPG. DJ has held leadership roles at various product & technology driven organizations including startup, hyper-growth and large scale, global environments.

DJ holds a bachelor’s degree in computer engineering from University of Illinois at Chicago and an MBA from Purdue University.

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Kim Estrada

SVP of Professional Services

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Kim Estrada Headshot

Kim Estrada

SVP of Professional Services

Kim brings over 20 years of experience in Professional Services and Customer Experience & Support within the enterprise software industry, leading global initiatives and driving success in high-growth organizations

Her leadership background spans a variety of industry solutions, including Research Management, ERP, Cloud Communications, Field Services, Technology Business Management, and Consumer Electronics.

At Cayuse, Kim oversees Customer Onboarding, Technical and Managed Services, Customer Enablement, and Solution Support.

Kim holds a bachelor’s degree in Business Administration from the University of Phoenix and has completed master’s-level studies in Human Resource Management at Villanova University.