The team behind your after-hours calls.

Lexis Vornheder is the Operations Manager at On Call Central, and has helped with just about every aspect of the business since joining the team in 2017. A native of Harrison, Ohio, Lexis did the right thing by attending the University of Kentucky, where she completed a double major in Marketing and Management and earned valedictory honors in her graduating class. True to the mantra "hire people smarter than you," she is a genuine jack-of-all-trades whose work spans operations, account services, human resources, finance, and customer support. We can hand her a complex project with only the broad strokes and trust that she will drive it to completion accurately and efficiently every time. When Lexis approached us about a position, we replied by saying, "First, you're hired!" She lives on a farm in West Harrison, Indiana, with her husband and young daughter.

Barbara Rasponi has been helping spread the word about On Call Central since 2016. You are on this website because of Barbara's efforts. She leads On Call Central's digital marketing, including paid search, social media, display advertising, website strategy, and lead generation campaigns. Barbara turns data into practical marketing plans that help more medical practices find, understand, and connect with On Call Central. Her work includes campaign management, performance optimization, messaging, and ongoing improvements to how prospects move from first click to first conversation. She holds a Bachelor's degree in Business Administration and Marketing from the Florida Institute of Technology. Barbara lives in Tampa, Florida, with her husband and their two children.

Claire Preziosi is the first person most practices meet at On Call Central. As Director of Business Development, she guides prospective customers from that first conversation all the way through launch, helping them understand how On Call Central can benefit their practice and making sure everything is in good shape before the account goes live. Claire joined in September 2019 after serving as Director of Training and Field Development at London Luxury and, before that, managing Microsoft Dynamics AX implementation nationwide at Mattress Firm. She holds a degree from Arizona State University, works out of our greater Cincinnati office, and is deeply involved in community service throughout the Cincinnati and Northern Kentucky area.

A.C. Chan makes sure On Call Central's growing client base receives top-tier service. She onboards medical practices and leads the team handling email and phone support, troubleshooting issues across office phones, personal phones, our mobile app, and the On Call Central system. She customizes phone trees to fit each practice's needs, produces professional recordings and video tutorials, writes help desk articles, analyzes call quality, and manages customer subscriptions. A.C. first joined as an intern before coming aboard full time in May 2021, and has since streamlined our support desk with tools that speed up response times and keep customers happy. She holds a Master's degree in Corporate and Organizational Communication and a Bachelor's in Organizational Communication from Western Kentucky University.

Krasimir has been programming and leading software development teams for almost 20 years, filling in multiple roles (web developer, project manager, product manager, business analyst). He is a big proponent of clean coding and following best software development practices.

Matthew Schumacher is responsible for the overarching technical infrastructure of On Call Central. Matthew is an expert Linux systems administrator and ensures that On Call Central's infrastructure is as resilient and fault-tolerant as possible. He is an avid pilot, and for the last 9 years has been building his own single-engine aircraft out of his garage; he claims it will be complete "any day now."

Dimitar is responsible for much of the backend logic and telephony functionality in On Call Central, and has been the primary developer responsible for our REST API. He is well-versed in modern full-stack and MVC frameworks, databases, ORMs, and JavaScript. He is a diligent and fast worker, and helps keep the product moving in the right direction.

Angel Draganov is the primary developer of On Call Central's mobile platform. With more than 10 years of development experience, Angel has deep knowledge of front-end mobile application development, as well as technologies that enable streamlined cross-platform app distribution. Angel is a beard aficionado and has more than 20 years of facial hair grooming experience.