Sr. Full Stack Software Engineer

Relha LLC; Sunnyvale (CA); On-site; USD 140,000 - 210,000; Full time

Job summary

Fiserv, a global leader in Fintech and payments, seeks a Senior Full Stack Software Engineer (Payments) to join the Clover platform team in Sunnyvale, CA. You will design, develop, and maintain scalable web applications and RESTful APIs across the full stack, ensuring reliable payment processing for millions of transactions daily.

Collaborate with product, design, and architecture teams; mentor junior engineers; participate in on-call rotations; contribute to code quality, testing, and CI/CD

Qualifications

• 6+ years of professional software development delivering production-grade, full-stack web applications.
• Backend development with Java and Spring Boot to design scalable microservices.
• Experience containerizing and deploying workloads in Kubernetes.
• Strong experience with relational databases, especially MySQL.
• Designing secure, performant RESTful APIs for web and mobile clients.
• Proficient with Git, CI/CD pipelines, and automated testing.

Responsibilities

• Lead the full-stack design, development, and implementation of scalable software applications and user interfaces.
• Collaborate with product, design, and architecture teams to translate business goals into frontend workflows and backend specs.
• Write, test, and debug frontend and backend components to ensure latency, responsiveness, and reliability.
• Maintain and evolve existing payment codebases while guiding architectural design and code reviews.
• Mentor engineers and driving technical excellence within the team.
• Participate in on-call and release-management rotations to sustain production readiness.
• Responsibilities may be adjusted as necessary.

Skills

Java

Spring Boot

Kubernetes

REST APIs

MySQL

CI/CD

Git

Distributed systems

Tools

Docker

Jenkins

Job description

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.

About your role:

Clover is a global leader in financial services technology, dedicated to building the smart point-of-sale (POS) and digital commerce networks that move money securely for millions of businesses daily. As a Senior Full Stack Software Engineer (Payments), you will join a high-performing product engineering team responsible for creating, enhancing, and maintaining our next-generation web applications, storefronts, and e-commerce APIs. In this role, you will work across the full stack to build and operate complex payment applications—including our Virtual Terminal, Invoicing, and hosted checkout tools—ensuring millions of global transactions are processed seamlessly every day.

What you’ll do:

Lead the full-stack design, development, and implementation of scalable software applications and user interfaces to support Clover’s payment processing ecosystem.

Partner deeply with cross-functional product, design, and architecture teams to gather complex requirements and translate business goals into intuitive frontend workflows and clean backend technical specifications.

Perform rigorous coding, testing, and proactive debugging across both frontend and backend components to guarantee optimal latency, responsiveness, and transaction reliability.

Maintain, refactor, and evolve existing full-stack payment codebases while leading architectural design and peer code review processes to uphold elite engineering standards.

Mentor engineers and emerging technical leaders, providing technical guidance to enhance the collective capabilities and product-thinking of the development team.

Participate in regular on-call and release management rotations to provide production support services and maintain high system availability.

Responsibilities listed are not intended to be all-inclusive and may be modified as necessary.

Experience you’ll need to have:

Core Engineering Foundations: 6+ years of professional software development experience delivering production-grade, full-stack enterprise web applications within a product-driven environment.

Java Mastery: Strong backend coding skills within the JVM ecosystem, utilizing Java and the Spring Boot framework to design, build, and scale distributed microservices.

Orchestration & Scale: Practical experience developing, containerizing, and deploying workloads within a Kubernetes (K8s) environment.

Data Layer Architecture: Solid experience working with relational databases, specifically MySQL or similar relational engines.

Platform Mindset: Ability to generalize complex business processes and build simple, flexible, and extensible core domain services that cleanly support multiple consumer products.

API Design: Deep expertise in designing, versioning, and maintaining secure, performant RESTful APIs for web and mobile clients.

DevOps Maturity: Strong proficiency with Git, automated testing frameworks, and managing automated CI/CD pipelines to ensure release stability.

Experience that would be great to have:

Payment Domain Expertise: Direct experience within the fintech, POS, banking, or e-commerce industries (familiarity with core checkout or payment transaction lifecycles is a massive plus).

System Hardening: Foundational understanding of web security protocols, network communication protection, data tokenization, and core cryptography.

Full-Stack Versatility: Comfortable working across multiple parts of the application stack and adjusting quickly in an iterative model where specifications and design layouts constantly evolve.

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

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

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.

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 [emailprotected] . 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.