Senior Systems Engineer Jobs in Rialto, CA (NOW HIRING)

Unlock your potential with Quantum ePay® We're a growing fintech company focused on delivering innovative payment processing solutions and merchant technology that helps businesses lower costs, earn more, and operate with confidence. We power mission-critical payment processing platforms used by merchants and partners across the U.S.

We are looking for a dependable, hands-on Senior Systems Administrator to support and help manage our internal IT environment, systems, infrastructure, and security operations. This role will work directly with our Chief Engineering Officer and serve as the senior onsite IT resource for employees, systems administration, technical escalations, and internal technology improvements.

This role is a great fit for someone who takes initiative, stays organized, communicates clearly, and enjoys keeping systems secure, reliable, and running smoothly. The Senior Systems Administrator will help ensure our employees have the access, equipment, systems, and support they need, while also helping strengthen our IT processes, documentation, and overall system reliability.

Responsibilities

• Manage and maintain company IT systems, user accounts, access permissions, hardware, software, and internal technology tools
• Administer Microsoft 365, Active Directory, email, MFA, shared drives, security groups, and other business systems
• Support onboarding and offboarding from an IT perspective, including account setup, access provisioning, equipment preparation, and access removal
• Serve as an escalation point for the Desktop Support Technician and assist with more complex technical issues
• Support laptops, desktops, printers, phones, conference room equipment, VPN access, and other onsite technology needs
• Monitor system performance, troubleshoot issues, and help resolve outages or service interruptions
• Maintain endpoint security, patching, device compliance, antivirus/EDR tools, and system updates
• Support network equipment and basic network troubleshooting, including firewalls, switches, wireless access points, DNS, DHCP, and VPN
• Maintain backups, disaster recovery procedures, and business continuity documentation
• Track IT assets, licenses, equipment inventory, and system documentation
• Create and maintain IT procedures, troubleshooting guides, onboarding/offboarding checklists, and internal support documentation
• Coordinate with vendors and service providers as needed
• Partner with the Chief Engineering Officer on IT priorities, security improvements, system upgrades, and internal technology projects
• Identify opportunities to improve IT processes, reduce recurring issues, and strengthen system reliability and security

Qualifications

• 5+ years of experience in systems administration, IT administration, infrastructure support, or a similar role
• Strong experience with Microsoft 365, Active Directory, Windows environments, user access management, and endpoint support
• Comfortable supporting both hardware and software issues in an onsite office environment
• Working knowledge of networking concepts including DNS, DHCP, VPN, firewalls, switches, and wireless networks
• Experience with endpoint management, patch management, device security, backups, and system monitoring
• Solid understanding of security best practices including MFA, least privilege access, phishing awareness, endpoint protection, and user access reviews
• Ability to troubleshoot technical issues independently and communicate updates clearly
• Strong documentation habits and attention to detail
• Comfortable working in a smaller company environment where priorities may shift and ownership is important
• Professional, dependable, responsive, and service-minded
• Able to communicate clearly with both technical and non-technical employees

Nice to Have

• Experience in fintech, payment processing, banking, financial services, or another compliance-focused environment
• Familiarity with PCI DSS, SOC, or similar security/compliance frameworks
• Experience with EDR/MDR tools, vulnerability scanning, SIEM tools, or security monitoring platforms
• Experience supporting both Windows and Mac devices
• PowerShell scripting or basic automation experience
• Experience improving onboarding/offboarding processes, access control, documentation, or IT asset management
• Certifications such as CompTIA Security+, Network+, Microsoft certifications, or similar
• Prior experience leading a small IT support function or serving as the primary IT point of contact for a business

Salary:

This role includes biannual profit-sharing bonuses as part of a total compensation package, in addition to a full range of medical, dental, retirement planning, and other benefits.

• Salary range: $85,000 - $105,000
• Salary including biannual profit-sharing bonus and comprehensive benefits program range (annualized): $109,725 - $ 133,725

Location: This role requires the employee to work fully onsite at our Anaheim Hills location.

Why Work Here?

• Awarded Top Workplace of Orange County by the OC Register!
• Flex PTO!
• New state-of-the-art, open-concept facility with stand-up desks, balance boards, stationary bikes, and more!
• Work hard, play hard culture!
• Monthly Beer Socials and BBQs!
• Proven "promote from within" mentality!
• Benefit offerings:
• Medical, dental, vision, acupuncture, and chiropractic
• 401k Safe Harbor; 100% employer match processed semi-monthly, up to 4%
• Profit Sharing; paid on a biannual basis