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

Fiserv · Sunnyvale, United States · full time · On site · September 15, 2026

Sign up to apply
Your first one is free
Posted September 15, 2026 · Read from Fiserv
Why a CV for this job?

94% of employers say their filters drop qualified candidates whose CV does not match the ad's exact criteria (Harvard Business School, 2021).

  • They see what they asked for, first. Your experience that matches the ad leads, in the ad's own words, so someone skimming finds it in seconds.
  • It gets past the software. Many larger employers use software that ranks CVs by how closely they match the ad, often before anyone reads them.
  • In the language of the ad. An ad written in Spanish gets a CV in Spanish, even when yours is in Portuguese.
  • Your facts, nothing invented. Your own experience, reordered and reworded. What the ad wants and your CV does not show is listed for you to add, only if it is true. You check it before you send it.
See an example

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.

Salary Range

$140,000.00 - $210,000.00

These pay ranges apply to employees in Sunnyvale, California. Pay ranges for employees in other states may differ.

It is unlawful to discriminate against a prospective employee due to the individual's status as a veteran.

For incentive eligible associates, the successful candidate is eligible for an annual incentive opportunity which may be delivered as a mix of cash bonus and equity awards in the Company’s sole discretion.

Thank you for considering employment with Fiserv. Please:

  • Apply using your legal name
  • Complete the step-by-step profile and attach your resume (either is acceptable, both are preferable).

Benefits at Fiserv:

  • Fuel Your Life program to support your physical, financial, social, and emotional well-being
  • Paid holidays and generous time away policies
  • No-cost mental health support through Employee Assistance Programs
  • Living Proof program to recognize your peers’ extra effort with points redeemable for rewards
  • Eight Employee Resource Groups to foster a collaborative culture and expand your network
  • ·Unparalleled professional growth with training, development, and internal mobility opportunities
  • Medical, dental, vision, life, and disability insurance options available from day one
  • Retirement planning and discounted shares with the Employee Stock Purchase Plan
  • Tuition assistance and reimbursement program
  • Paid parental, caregiver, and military leave

#LI-SH2

Our commitment to Equal Opportunity:

Fiserv is proud to be an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, national origin, gender, gender identity, sexual orientation, age, disability, protected veteran status, or any other category protected by law.

If you have a disability and require a reasonable accommodation in completing a job application or otherwise participating in the overall hiring process, please contact AskHR.US@fiserv.com. Please note our AskHR representatives do not have visibility to your application status. Current associates who require a workplace accommodation should refer to Fiserv’s Disability Accommodation Policy for additional information.

Note to agencies:

Fiserv does not accept resume submissions from agencies outside of existing agreements. Please do not send resumes to Fiserv associates. Fiserv is not responsible for any fees associated with unsolicited resume submissions.

Warning about fake job posts:

Please be aware of fraudulent job postings that are not affiliated with Fiserv. Fraudulent job postings may be used by cyber criminals to target your personally identifiable information and/or to steal money or financial information. Any communications from a Fiserv representative will come from a legitimate Fiserv email address.

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.
Employer
Fiserv
Location
Sunnyvale, United States · On site
Contract
full time