Fiserv

Sr Software Engineer (React, JavaScript, .net)

Fiserv$90K — $127K *
Information Technology
5 - 7 years of experience
Job Overview by Ladders

Qualifications

  • Bachelor’s degree in Computer Science, MIS, or equivalent experience
  • 5+ years of experience in full-stack web application development
  • Expertise in C# and ASP.NET Core
  • Proficiency in React with modern development patterns
  • Experience with TypeScript, JavaScript (ES6+), HTML5, CSS3
  • Strong SQL Server and T-SQL skills for data management
  • Experience with REST API development and security practices

Responsibilities

  • Design and maintain responsive web applications using React and ASP.NET Core
  • Develop and support robust RESTful APIs and backend microservices in C#
  • Translate business needs into technical solutions, including UI workflows and data models
  • Optimize SQL Server database schemas and queries for high-volume usage
  • Implement security practices in coding and access controls
  • Create reusable front-end components and backend services
  • Collaborate with cross-functional teams for feature delivery
  • Engage in code reviews, system troubleshooting, and performance monitoring
  • Contribute to technical documentation for team efficiency

Benefits

  • Fuel Your Life program for well-being
  • Generous time off and paid holidays
  • Mental health support through Employee Assistance Programs
  • Living Proof program to recognize and reward peer contributions
  • Employee Resource Groups for networking and collaboration
  • Professional growth opportunities with training and internal mobility
  • Comprehensive insurance options from day one
  • Retirement planning and discounted Employee Stock Purchase Plan
  • Tuition assistance and reimbursement
  • Paid parental, caregiver, and military leave
Full Job Description

Job Title

Sr Software Engineer (React, JavaScript, .net)

About your role:

Join the Client Services technology team as a Full-Stack Web Developer to build and enhance the high-value, data-driven applications that power our global support operations. In this role, you will work across a modern tech stack—utilizing React and TypeScript on the front end alongside C# and ASP.NET Core on the back end—to turn complex business data workflows into secure, scalable, and intuitive user experiences. By partnering with cross-functional business and technical teams, your engineering output will directly improve operational readiness, speed-to-market, and the overall efficiency of our client-facing services ecosystem.


What you’ll do:
  • Design, develop, and maintain responsive web applications using React and ASP.NET Core to support modern Single Page Application (SPA) experiences.
  • Build, evolve, and support robust RESTful APIs and backend microservices in C# with a strong emphasis on maintainability, scalability, and clean architecture.
  • Translate complex business needs into well-structured technical solutions, including UI workflows, API contracts, and performant data models.
  • Develop, optimize, and maintain SQL Server database schemas, T-SQL queries, stored procedures, and advanced indexing strategies to support high-volume data use cases.
  • Implement enterprise-grade security practices, including secure coding patterns, robust authentication/authorization protocols, and least-privilege access controls.
  • Create reusable, tested front-end components and backend services using modular design patterns that facilitate long-term codebase health.
  • Collaborate closely with product owners, technical analysts, and cross-functional support teams to reliably deliver features from concept and build to release and support.
  • Participate actively in code reviews, system troubleshooting, performance tuning, and production monitoring to ensure top-tier software quality.
  • Contribute to essential technical documentation, including design notes, operational runbooks, and supportability guides to enhance team velocity.
  • Responsibilities listed are not intended to be all-inclusive and may be modified as necessary.

Experience you’ll need to have:
  • Bachelor’s degree in Computer Science, Management Information Systems (MIS), or equivalent practical/professional work experience.
  • 5+ years of professional hands-on experience designing, building, delivering, and supporting full-stack web applications.
  • Strong backend proficiency in C# and modern .NET development (ASP.NET Core).
  • Strong frontend proficiency in React utilizing modern patterns, including functional components, custom hooks, and component design.
  • Production experience using TypeScript and modern JavaScript (ES6+) alongside HTML5 and CSS3 with an awareness of responsive layouts and accessibility.
  • Solid database expertise with SQL Server and T-SQL, including data modeling, advanced querying, and schema optimization.
  • Proven experience building, securing, and consuming REST APIs for client-device and web-client interactions.
  • Familiarity with modern software development practices, including Git-based version control (advanced branching and merging), CI/CD concepts, automated unit/integration testing, and log-based production troubleshooting.
  • Excellent written and verbal communication skills with the ability to work cross-functionally and translate business requirements into software solutions.

Experience that would be great to have:
  • Experience utilizing Entity Framework Core or an equivalent Object-Relational Mapping (ORM) framework.
  • Practical experience implementing authentication and authorization standards (e.g., OAuth2, JWT, or Microsoft Entra ID).
  • Familiarity with containerization (Docker) and deploying workloads across cloud ecosystems (Azure/AWS) or hybrid/on-prem environments.
  • Knowledge of asynchronous messaging patterns, queuing architectures, and background processing jobs.
  • Exposure to enterprise reporting, data analysis, or embedded analytics tools such as SSRS or Power BI.
  • Previous engineering experience within the payments, fintech, or financial services industries.
  • Comfort working with modern engineering tooling, including Visual Studio/VS Code, SSMS, Azure DevOps, GitHub Actions, or IIS.

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.

Travel:

  • Approximately 10% travel off-site or to other office locations is expected.

 

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

Salary Range:

$90,000.00-$127,000.00

These pay ranges apply to employees in Maryland. Pay ranges for employees in other states may differ. Certain Positions are Commissions eligible.

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).

About Fiserv

CashEdge(R) provides infrastructure that global financial institutions rely on to extend their online channels and enhance customer profitability. CashEdge delivers secure Online Money Movement and Advanced Account Aggregation platforms that power specialized retail banking and advisor applications. These proven solutions enable CashEdge's clients to create compelling online offerings that attract customers, generate revenues, and reduce costs. CashEdge serves top-tier financial institutions around the world. Clients and partners include Vanguard, RBC Financial Group, CIBC, Yahoo! Finance, Digital Insight, First Data, TD Canada Trust, NYCE, Laurentian Bank, Financial Fusion and Corillian. CashEdge has offices in New York and Silicon Valley.

Fiserv Careers

Join the Fiserv team today and be part of a dynamic company known for innovation, leadership, and a commitment to the professional growth of its employees. At Fiserv, we offer more than just job opportunities; we provide a platform where skills are honed, leadership is cultivated, and career aspirations are achieved. Work You’ll Do At Fiserv, we are constantly on the lookout for talented individuals eager to thrive in a culture that fosters growth and diversity. Our team is composed of professionals who lead the way in financial services technology. By joining us, you will collaborate with some of the brightest minds in the industry, working together to solve complex challenges and deliver innovative solutions that impact millions of people every day. Explore Our Job Opportunities Whether you're seeking an entry-level position or a more senior role, Fiserv offers a range of career paths in areas such as software development, project management, financial analysis, and client services. Our hiring process is designed to identify and attract individuals who are not only technically proficient but who also embody our values of integrity and responsibility. Internship Programs Kickstart your career with a Fiserv internship. Our internships provide invaluable workplace experience and networking opportunities that often lead to full-time employment. As an intern, you’ll gain hands-on experience while working on meaningful projects that directly contribute to the company’s goals. Benefits and Culture Fiserv is committed to the well-being and continuous development of our employees. We offer competitive benefits including health, dental, and vision insurance, as well as opportunities for professional development through leadership training and diversity programs. Our culture is one of inclusion, where every team member is valued and has the opportunity to contribute to our success. Career Growth and Development We believe in nurturing the potential of our employees through career development initiatives and continuous learning opportunities. At Fiserv, you will find a supportive environment where you can grow your career through on-the-job experiences, mentoring, and formal training. Stay Connected Join Our Team Search open positions that match your skills and interests. We look for passionate, curious, creative, and solution-driven team players. Start your journey with Fiserv today and help shape the future of financial services. Keep Up to Date Stay ahead with career tips, insider perspectives, and industry-leading insights you can put to use today—all from the people who work here. Job Alert Emails Personalize your subscription to receive job alerts, latest news, and insider tips tailored to your preferences. Discover the exciting and rewarding career opportunities that await at Fiserv. Explore, innovate, and grow with Fiserv. Let your career journey begin here, where you can make a real difference in the world of finance.
Learn more about Fiserv
Size
44,000 employees
Market Cap
$63.4 billion
Industry
Net Income
$958 million
Founded
1984
5 Year Trend
+24.1%
Revenue
$14.8 billion
NASDAQ

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