Sr. Security & Test Engineer - Device OS (PKI & Firmware Security)

Calling all innovators - find your future at Fiserv. We're Fiserv, a global leader in Fintech and payments, and we move money and information in a way that moves the world. We connect financial institutions, corporations, merchants and consumers to one another millions of times a day - quickly, reliably, and securely. Any time you swipe your credit card, pay through a mobile app, or withdraw money from the bank, we're involved. If you want to make an impact on a global scale, come make a difference at Fiserv. Job Title Sr. Security & Test Engineer - Device OS (PKI & Firmware Security) About your role: Clover, a Fiserv company, is a global leader in point-of-sale platforms powering millions of small businesses worldwide with integrated hardware, software, and payment solutions. In this role, you will join the DeviceOS team, which owns all platform software, secure boot infrastructure, and mass manufacturing software running on Clover hardware. You will design, build, and execute security validation strategies, manage embedded PKI/HSM trust architectures, and ensure our POS devices meet strict regulatory and cryptographic compliance standards. What you’ll do: Design, develop, and execute comprehensive security and testing strategies for the Device OS powering Clover Point of Sale devices. Manage and validate PKI infrastructure, Certificate Authority (CA) lifecycles, and Hardware Security Modules (HSMs) for secure device provisioning and key management. Take direct accountability for overall platform security, vulnerability management, and operational quality across Clover hardware product lines. Interpret PCI-PTS and PCI-PIN specifications to design and execute compliance, penetration testing, and risk validation workflows. Audit and secure CI/CD build pipelines, automated deployments, and golden images to maintain end-to-end supply chain security. Troubleshoot complex issues related to embedded cryptography, TLS/mTLS, certificate lifecycle tools, and secure bootloaders. Responsibilities listed are not intended to be all-inclusive and may be modified as necessary. Experience you’ll need to have: 5+ years of professional experience in Software Security, PKI Engineering, AppSec, or Software QA/Testing. Deep hands-on experience with Public Key Infrastructure (PKI), Certificate & Key Management, and Hardware Security Modules (HSMs, e.g., Thales). Strong domain knowledge of security protocols, symmetric/asymmetric encryption, TLS/mTLS, and digital certificates. Experience with vulnerability management, security scanning tools, and risk assessments within Linux, Android (AOSP), or cloud/embedded infrastructure. Practical scripting skills (Python, PowerShell, or Bash) to automate security workflows, log extraction, and diagnostic testing. Familiarity with secure CI/CD pipelines, version control, and infrastructure orchestration (Jenkins, GitHub Actions, Terraform, Jira). Excellent communication skills with the ability to partner across engineering, GRC, and product teams to remediate findings. Experience that would be great to have: Experience validating software or hardware for certified/regulated standards (PCI-PTS, PCI-PIN, SOC 2, or ISO 27001). Hands-on exposure to penetration testing tools (e.g., BurpSuite, Metasploit) or cloud security posture management (e.g., Wiz, AWS SSM). Experience with Android test frameworks (UIAutomator, adb debugging, Logcat analysis). Prior experience managing supply chain security, golden image retention, or mass manufacturing provisioning software. How you’ll work: This role is on-site Monday through Friday. Fiserv considers in-person collaboration to be an essential part of this role as in-person office experiences help you with your overall onboarding experience and leads to stronger productivity. This role requires use of a computer and audio equipment.   Benefits at Fiserv: Fuel Your Life program to support your physical, financial, social, and emotional well-being Paid holidays and