Senior iOS Engineer – Payments & Hardware Integrations

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

About Your Role

Clover is a global leader in point-of-sale platforms powering millions of small businesses worldwide with integrated hardware, software, and payment solutions.

We are seeking a Senior iOS Engineer who enjoys bridging high-level mobile software with physical hardware. Based at our campus in Sunnyvale, CA, you will serve as a hands-on technical lead driving mobile hardware integrations, Bluetooth reader SDKs, and core transaction flows across our native iOS framework. In this role, you will work closely with our on-site hardware labs, product teams, and Core Payments engineering to ensure fast, reliable, and secure mobile payment experiences. If you love building software that interacts with physical accessories—from Bluetooth readers to smart terminal devices—we want to talk to you!

What You Will Do

• Hardware & SDK Engineering: Design, build, and maintain modular native iOS SDKs and frameworks that communicate with Bluetooth Low Energy (BLE) card readers, smart accessories, and next-generation terminal hardware.
• Core Payment Integrations: Partner with backend and Core Payments teams to integrate transaction processing, tokenization, refunds, and secure cryptographic communications on iOS.
• On-Site Prototyping & Lab Debugging: Leverage our state-of-the-art Sunnyvale hardware lab for real-time hardware-in-the-loop debugging, reader firmware testing, and performance optimization.
• System Architecture: Write clean, maintainable Swift and Objective-C components emphasizing thread safety, low latency, and robust offline-first execution.
• Global Team Alignment: Serve as a U.S.-based technical lead for iOS hardware integrations, bridging communication between local lab teams and global engineering groups.

What You Need to Have

• iOS Mastery: 5+ years of hands-on experience building, testing, and shipping production-grade native iOS applications or frameworks using Swift and Objective-C.
• Hardware & Peripheral Integration: Hands-on experience connecting iOS applications to external hardware accessories or peripherals using CoreBluetooth, Bluetooth Low Energy (BLE), MFi (Made for iPhone), or USB interfaces.
• Framework Architecture: Deep understanding of iOS framework design, API architecture, multithreading, memory management, and asynchronous networking.
• Security & Network Foundations: Exposure to secure key management, cryptographic principles (e.g., AES, RSA, tokenization), or REST/WebSocket APIs.
• Debugging & Problem-Solving: Curiosity and drive to troubleshoot complex edge cases spanning software, network protocols, and physical hardware layers.

Experience that would be great to have

• Card Reader & Payment Experience: Any prior experience working with payment processors, card readers (e.g., Clover, Square, Stripe Terminal, Ingenico, Verifone), or point-of-sale (POS) systems is highly valued.
• Compliance Exposure: Familiarity with payment industry standards (PCI-DSS, PCI-PTS, EMVCo) or device certification workflows.
• C/C++ Interop: Experience writing or maintaining shared native C/C++ libraries wrapped for iOS via Objective-C++ or Swift C-interop.

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 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

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Salary Range

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.

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).

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 [email protected]. 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.

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