Financial Systems Software Developer (Public Sector)
System One Holdings, LLC
About the role
Responsibilities
- Support, maintain, and enhance custom-built and legacy financial applications, often with minimal documentation
- Analyze application behavior directly from source code and implement logic changes safely and accurately
- Design and develop custom Finance-Technology solutions, including systems for payments, billing, reconciliation, and reporting
- Integrate financial systems with enterprise ERP platforms, payment processors, and external systems
- Implement and improve UI/UX using modern, responsive, mobile-first design practices
- Collaborate with Finance subject-matter experts (SMEs) to translate business and statutory requirements into technical solutions
- Support system integrations, data exchanges, and troubleshooting across multiple platforms
- Contribute to documentation, knowledge transfer, and source-code repository management
- Participate in daily team check-ins and stakeholder discussions as required
Requirements
- Proficiency in HTML, CSS, JavaScript, modern CSS frameworks (Bootstrap, Tailwind), C#, ASP.NET (WebForms, MVC, ASP.NET Core), Microsoft SQL Server, Azure Entra ID / Azure AD B2C, DevOps tools, IIS, Windows OS, networking concepts
- At least 7 years supporting and maintaining legacy, high-code applications with minimal documentation within the last 5 years
- Minimum 7 years developing/supporting customized Finance-Technology applications such as payment processing, reconciliation, billing, or financial transaction systems
- One relevant project in the last 3 years with documented contributions
- At least 5 years of system integration experience with Tyler Technologies MUNIS or comparable enterprise ERP used in SLED environments, including API, database, or file-based integrations, data mapping, and troubleshooting
- Recent (within last 3–5 years) experience (3+ years) integrating with Paymentus or similar government payment platforms, including redirects, iframes, deployment, testing, and troubleshooting
- At least 7 years experience in UI/UX development focusing on responsive, mobile-first design, with examples of measurable user experience improvements
- Bachelor’s degree in Computer Science, Information Systems, or related field or equivalent experience
- Relevant software development or cloud certifications (Microsoft, Azure, .NET, DevOps) preferred
About System One
System One, and its subsidiaries including Joulé and Mountain Ltd., are leaders in delivering outsourced services and workforce solutions across North America. We help clients get work done more efficiently and economically, without compromising quality. System One not only serves as a valued partner for our clients, but we offer eligible employees health and welfare benefits coverage options including medical, dental, vision, spending accounts, life insurance, voluntary plans, as well as participation in a 401(k) plan.
System One is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex (including pregnancy, childbirth, or related medical conditions), sexual orientation, gender identity, age, national origin, disability, family care or medical leave status, genetic information, veteran status, marital status, or any other characteristic protected by applicable federal, state, or local law.
Skills
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