Our team embodies our core values:

We are transparent, visible and trusted with over 20 years of experience

Our Valuable Team Members

Jeff Robertson CEO | President

A passion for Healthcare is the best way to describe Jeff Robertson. He has a unique, varied and extensive background in Healthcare that covers a wide array of experience encompassing 25 years. Jeff is board certified by the MGMA as a Medical Practice Executive and is a proud active member of MGMA. Jeff is also an active member of the Healthcare Business Management Association (HBMA) and continues to keep his knowledge current and focused on future trends and initiatives and how they affect our clients and their Clinic. Jeff has been actively running the Revenue Cycle Management and Practice Management divisions since 1997. Jeff Robertson has spent over 21 of the last 25 years in Independent Physician Clinics with a special focus on Medical Billing/Revenue Cycle Management, Healthcare IT, Clinical Workflow Analysis and Bookkeeping and Financials for Independent Medical Practices. His passion and love of teaching, consulting and finding a better, more efficient way to build processes into a clinic has led to him being labeled the “Practice Fixer”.

To date, he has installed, configured, trained and consulted over 400 Independent Physician Clinics across the country and has learned valuable lessons from each of them to share with all of our future clients.


Julius Cabacungan Director of IT

Julius has been in the fast paced IT support industry for more than 20 years. He utilizes his accumulated experience as Senior Systems and Network administrator to quickly analyze the variety of IT situations and provide the most effective and efficient solutions. Since Julius joined Nexsys, he has integrated his vast IT knowledge with the understanding of Electronic Medical Records systems. This resulted in helping all Nexsys clients have operational integrity of their EMRs and computer systems. Julius has bachelor’s degree in Electronics Engineering and has MCSE (Microsoft) and CCNA (Cisco) certifications. He enjoys sports and loves playing tennis. He and his wife have two daughters.

Gelson Viera Accountant

Gelson Vieira is a 20 plus year veteran in the area of finance, with 8 years of experience in external audit at Coopers & Lybrand. He also spent time with the internal auditing department in Europe and the Middle East during his years at AIG Insurance Company.  Gelson’s tremendous knowledge of multiple languages including Portuguese, Spanish, French and Italian made him a great asset for the international companies and divisions where he worked.
Gelson has ran the Practice Management Division for Nexsys for over 5 years and in that capacity has managed the Bookkeeping, Financials; which include Cash Flow Projections for Medical Practices throughout the country. He is uniquely qualified to ensure our clients systems and processes are transparent and accountable and minimize the need for our clients to employ a Practice Administrator or Office Manager, thereby keeping their staffing and overhead to a minimum. Gelson also helps the team of Billers and Coders in building out the Compensation Plans for our client Physicians. Many of our client groups have very detailed and complex compensation plans that involve many factors that our Accounting and Billing team work together to formulate and distribute to our clients. Additionally, Gelson manages the Accounts Payables, Membership Management and Payroll for our clients He is an invaluable member of our team and to each of our clients who rely on his accuracy, integrity and accountability. 

Jerson Flores IT Administrator

Jerson has been an IT System Administrator/Engineer for over 10yr. has extensive experience as a Senior Technical Support Administrator and Network Engineer. He built valuable experience providing in-house, on-site and remote end user technical support throughout his career. Jerson has also provided project management, server administration, deployment and infrastructure support for medium sized and enterprise businesses.

Jerson focuses his time on automation and customization of the EHR for improved workflow. Jerson holds a Bachelors Degree in Software Engineering and multiple Certifications including, MTA, MCSE, CCA-V. He spends most of his free time with his two daughters or on his hobbies spare. as he’s an avid Photographer/Musician

Debbie Hernandez, CPC Certified Professional Coder/Billing Manager

Debbie leads the Billing team at Nexsys and shares her knowledge and experience which she has accumulated over 10+ years managing the Billing Practices, Policies and Procedures for most Specialties. She excels at managing our Client’s accounts and facilitating and supporting the Nexsys team to ensure all of our clients are given the dedication and detail that each account requires. Debbie has proven to have excellent communication skills with our clients and their patients with compassion and patience. Debbie is also responsible for helping to formulate and prepare complex commission structures for some of our larger groups. She is a valuable part of the Nexsys team and a great team player.

Alex Lizarraga Medical Billing Account Manager

Alex has been a vital team member and mentor for Nexsys since joining our team in 2016. Alex is a trusted source for taking care of all of our clients needs and reports. Alex plays a key role in providing analysis and data to help both Nexsys Management as well as our clients; to make informed decisions supported by Data and Metrics. Alex is supporting our clients with everything from Coding help, payer analysis as well as helping the patients that put their faith in our clients and who we are all here to support. Her positive attitude and tremendous knowledge is a big part of the Nexsys culture that we try to share with all of our clients.