VoIP Systems Engineer

ManTech International Corp

McLean, VA

JOB DETAILS
SALARY
$165,900–$295,300 Per Year
SKILLS
Best Practices, Billing, Call Routing, CentOS, Communication Skills, Cross-Functional, Customer Relations, Customer Support/Service, Data Analysis, Federal Contracts, Federal Government, Government Contracts, Government Intelligence, High School Diploma, ISDN (Integrated Services Digital Network), Identify Issues, Intelligence Agencies, Internet Application, Internet Security, Ksh (Korn Shell) Scripting, Linux Administration, Linux Operating System, Office Equipment, Oracle Certifications, Oracle DBA (Database Administrator), Performance Tuning/Optimization, Presentation/Verbal Skills, Ruby, Ruby on Rails, Scripting (Scripting Languages), Sensitive Compartmented Information (SCI), Service Delivery, Software Administration, Software Development, Sybase Powerbuilder, System Integration (SI), Systems Administration/Management, Systems Engineering, Technical Writing, Telephony, Testing, Top Secret Clearance, Training/Teaching, Ubuntu, VoIP (Voice over IP), Voice Response Systems, Web Hosting, Writing Skills
LOCATION
McLean, VA
POSTED
1 day ago

General information

Requisition #

R67420

Locations

USA-VA-McLean

Posting Date

04/29/2026

Security Clearance Required

TS/SCI w/ Poly

Remote Type

Onsite

Time Type

Full time

Description & Requirements

Unlock the secrets of intelligence with MANTECH! Join a dynamic team at the forefront of national security, providing advanced solutions to government intelligence agencies. Since 1968, we've been solving the toughest challenges with groundbreaking tech. Explore thrilling projects in Digital Transformation, Cybersecurity, IT, Data Analytics and Software Development. Elevate your career and make a difference. Your adventure begins now-unleash your potential with MANTECH!

MANTECH seeks a motivated, career and customer-oriented VoIP Systems Engineer to join our team in McLean, VA. In this role, you'll combine expertise in telephony systems, Linux server management, and software development, focusing on VoIP, analog, ISDN systems, and Ruby on Rails for telephony applications.

Responsibilities include, but are not limited to:

  • Design, develop, and maintain voice media gateways for VoIP, analog, and ISDN systems. Install, configure, and troubleshoot telephony hardware and media gateways across secure networks.
  • Leverage BESS Billing and Provisioning Tools to optimize telephony systems and ensure seamless service delivery.
  • Configure and maintain Linux servers (Ubuntu, CentOS) for hosting telephony and web applications, ensuring performance, security, and scalability. Develop and troubleshoot applications using PowerBuilder, Korn shell, and Ruby on Rails.
  • Integrate telephony systems (e.g., IVR, call routing) into web applications using Ruby on Rails. Modernize legacy code and ensure reliable operation of telephony solutions.
  • Maintain clear technical documentation and provide ongoing support for telephony system integration, performance optimization, and troubleshooting.
  • Provide training and guidance to team members and stakeholders on telephony system integration, BESS tools, and server management best practices. Ensure comprehensive understanding of application workflows and troubleshooting processes.
  • Provide local travel support between customer buildings or temporary assignment to alternate locations for special projects.
  • Work an 8 hour shift as part of a coverage team operating between 6:00 AM and 6:00 PM. May need to flex shift as required.

Minimum Qualifications:

  • High School Diploma with 13+ years of experience or an Associate's Degree with 11+ years of experience, or a Bachelor's Degree with 9+ years of experience.
  • Familiarity with BESS Billing and Telephony Provisioning Tools.
  • Experience integrating telephony systems with web applications (e.g., handling inbound/outbound calls, IVR, call routing).
  • Advanced knowledge of Linux server management (Ubuntu, CentOS), including installation, configuration, troubleshooting, and performance optimization.
  • Strong verbal and written communication skills to interact effectively with cross-functional teams.

Preferred Qualifications:

  • Proficiency in Ruby programming and the Ruby on Rails framework, along with strong experience in telephony system integration.
  • Experience with scripting languages, including PowerBuilder and Korn shell, for system administration tasks.
  • Oracle Database Administrator certification is a plus.
  • Experience in provisioning telephony services.

Clearance Requirements:

  • Must have a current/active TS/SCI with Polygraph

Physical Requirements:

  • Must be able to remain in a stationary position at least 50% of the time. Constantly operate a computer, phone, and other office equipment for extended periods of time.

The projected compensation range for this position is $165,900.00-$295,300.00. There are differentiating factors that can impact a final salary/hourly rate, including, but not limited to, Contract Wage Determination, relevant work experience, skills and competencies that align to the specified role, geographic location (For Remote Opportunities), education and certifications as well as Federal Government Contract Labor categories. In addition, MANTECH invests in its employees beyond just compensation. MANTECH's benefits offerings include, dependent upon position, Health Insurance, Life Insurance, Paid Time Off, Holiday Pay, short-term and long-term Disability, Retirement and Savings, Learning and Development opportunities, wellness programs as well as other optional benefit elections.

MANTECH considers all qualified applicants for employment without regard to disability or veteran status or any other status protected under any federal, state, or local law or regulation.

If you need a reasonable accommodation to apply for a position with MANTECH, please email us at careers@mantech.com and provide your name and contact information.

About the Company

M

ManTech International Corp

Our Mission Our mission is empowering our nation through a diverse and skilled workforce securely delivering innovative technology, consulting services and digital solutions for our customers’ mission success, every day. Our Vision Our vision is Securing the Future as the most trusted partner for U.S. Defense, Intelligence and Federal Civilian customers through the power of One ManTech. When these agencies think of an essential partner for their national and homeland security needs, they think ManTech. Our Values Our values are grounded in a bedrock of truth, integrity and caring for each other and the mission. We hold steadfast to: • TRUST – We earn and protect the trust of our customers, employees and investors through an enduring foundation of respect, fairness, credibility and honoring our commitments, always. • INCLUSION – We are an inclusive, diverse and talented workforce with a passion for mission success, intellectual capital, creativity and integrity. Our high ethical standards and investment in our people build confidence with our customers. • QUALITY– We deliver exceptional quality to customers through differentiated technology solutions and an uncompromising focus on excellence, value and innovation.
COMPANY SIZE
5,000 to 9,999 employees
INDUSTRY
Other/Not Classified
FOUNDED
1968
WEBSITE
https://www.mantech.com/about