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On Call Central
About On Call Central

The team behind your after-hours calls.

We're a small, focused team of engineers, operators, and clinicians who've spent the last 15+ years building a medical answering service that doctors actually want to use.

2008
Founded
8.2M
Calls handled per year
50+
Specialties served

A back-of-the-napkin idea.

On Call Central quite literally was a back-of-the-napkin idea. A logic diagram of the idea was drawn on the back of a cocktail napkin, and some months later a prototype of On Call Central was in place. The software has evolved enormously since that time (in fact, nearly nothing of the original code remains) and On Call Central now handles millions of calls in nearly every specialty of medicine.

Our Team

The people running the show.

From product direction and operations to marketing and a four-legged morale officer.

Sidney VanNess, Ph.D., Founder of On Call Central
Founder
Sidney VanNess, Ph.D.
Founder

Sidney VanNess is the founder of On Call Central, and is responsible for the overall direction of the company. A research scientist by training, he completed his doctoral research in the Molecular and Systems Pharmacology program at Emory University, where he conducted studies on the genetics underlying attentional disorders, and their influence on the response to drug therapies. Dr. VanNess has been involved in software development for 15 years, and is a co-author of the patent protecting portions of On Call Central's underlying technology.

Lexis Dole, Operations Manager
Lexis Dole
Operations Manager

Lexis Dole is the Operations Manager at On Call Central, and helps out with just about every aspect of the business. 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. Lexis embodies the mantra, "Hire people smarter than you." Her smarts and work ethic helped her earn valedictory honors in UK's graduating class. When Lexis approached us about a position at On Call Central, we replied by saying, "First, you're hired!"

Barbara Hoye, Chief Marketing Officer
Barbara Hoye
Chief Marketing Officer

You are on this website because of the efforts of Barbara Hoye. Barbara is the primary person responsible for On Call Central's search, social media, and display campaigns, and has helped spread the word about our software. She is responsible for providing innovative ideas and strategies for increasing lead generation in all marketing endeavors. In her spare time, Barbara runs marathons and enjoys jumping out of perfectly functional aircraft.

Stella, Chief Barking Officer
Stella
Chief Barking Officer

Stella was promoted to Chief Barking Officer at the tender age of four months. Her duties include greeting mail carriers, distracting interns, and attempting to play fetch in the middle of conference calls.

Engineers

The people who build it.

Software engineers, infrastructure specialists, and mobile developers behind the platform.

Krasimir Hristozov, Project Manager & Business Analyst
Krasimir Hristozov
Project Manager & Business Analyst

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, Systems Engineer
Matthew Schumacher
Systems Engineer

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 Rekinov, Software Engineer
Dimitar Rekinov
Software Engineer

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, Mobile Application Developer
Angel Draganov
Mobile Application Developer

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.

Ready to see what we've built?

Schedule a free 30-minute demo, or jump straight into a two-week trial with guided setup.